Cyberknife After RP and SRT

janekirstine
janekirstine Member Posts: 24 Member
Forum Friends!

Just wanted to sign in with details of our decisions in the PC journey. My husband has started Casodex/Lupron TIP and after scans and more scans, we have decided to go forward with Cyberknife to target the one known tumor/lesion on the sacral vertebra. We are both pretty excited about this, hoping that it will target the main source of the rising PSA. We realize there are more than likely other micrometastatic prostate cancer cells out there somewhere and feel that the hormone blockage will suppress them.

Thank you all again for your support. Just knowing that you are present online is a great comfort, and great motivator to be aggressive and questioning in working through treatment options. Jane


Background Clinical History:
14 Aug 2001 – 8.9 PSA
Biopsy 14 Aug 2001 – six cores. Three from right side of prostate are benign. Three from left side of prostate are involved with prostatic adenocarcinoma.
Gleason major pattern 4, Gleason minor pattern 3, pattern score 7

Radical Prostatectomy 20 Sep 2001 at Walter Reed Army Hospital Age: 52

Post surgery pathology report:
Multifocal carcinoma Gleason 3 and 4
Stage pT (5) 3b Nx
Surgical Margin: Negative
Lymph nodes negative for malignancy
Oct 2005 – 0.01
Oct 2006 - 0.02
Oct 2007 – 0.03
Oct 2008 – 0.10
(PSA on request from doctor for 2009)
Oct 2010 - 0.54
Oct 2010 - 0.62

Rising PSA detected in October 2010. Physical examination and follow up transrectal ultrasound showed a mass in the prostate bed (left anterior wall of the rectum). Biopsy performed on December 14, 2010. Pathology report showed a tumor with a growth pattern consistent with Gleason pattern 4+4=8.

Started radiation treatment on 23 Feb 2011 to 19 Apr 2011
Received 38 IMRT treatments using Calypso focusing

Aug 2011 - Nuclear Medicine bone imaging whole body – No definite metastatic lesions identified
Aug 2011 - CT Abdomen pelvis with contrast – No solid organ lesions or evidence of osseous metastatic disease, mildly enlarged left perirectal lymph node, borderline enlarged presacral lymph node.

Post radiation PSA
July 2011 – 1.76
Aug 2011 – 2.53
Sep 2011 – 3.78
Oct 2011 - 4.33

09 Oct 2011 - Fluoride bone scan identified spot on sacral spine
10 Oct 2011 - ProstaScint scan Negative

22 Oct 2011 - Started Casodex
07 Nov 2011 - MRI to further define spot found on fluoride scan
Tumor found near sacral spine. Consulted many doctors about Cyberknife for tumor.
Going forward with Cyberknife

08 Nov 2011 - First Lupron shot
Age now 62 years
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Comments

  • Swingshiftworker
    Swingshiftworker Member Posts: 1,017 Member
    Good luck!
    We often overlook the fact that that CK was first developed to treat many previously "inoperable" cancers -- including the brain, lungs and spine -- and that the treatment of PCa w/CK is a later application of the methodology.

    FWIW, one of the reasons CK is not considered for use w/PCa by Kaiser Permanente in NorCal (which has a CK facility in South San Francisco) is because PCa is technically not "inoperable" and because there are other treatments (such as robotic and open surgery and BT that Kaiser is heavily committed to) that are available to treat PCa. Of course, this begs the question of whether surgery and/or BT are actually better suited than CK for the treatment of PCa (in terms of effectiveness, the minimization of side effects and the enhancement of the patient's quality of life). However, Kaiser has apparently chosen to not even to consider this question and simply does not offer CK for PCa.

    Good luck in the treatment of your husband's spinal tumor as well as the metastasis of his PCa in general!
  • hopeful and optimistic
    hopeful and optimistic Member Posts: 2,339 Member
    Success
    I know a man who has had two tumors removed from his spine using cyberknife, and is going on with his life with hormones with no physical effects.

    Good choice, good luck
  • mrspjd
    mrspjd Member Posts: 694 Member
    Jane,
    Thanks for the update and sharing such a complete summary about your and your husband's PCa journey. Glad to read you’ve moved forward with a decision and plan since your last posts. From the info, it appears that the CK/SBRT tx is being used as a focal therapy to tx the tumor/spot found near the sacral spine identified by a fluoride PET bone scan.

    Coincidentally, there's a recent discussion on another thread about SBRT/CK as a focal tx for PCa tumors. It makes sense that SBRT/CK can be used as a focal tx for PCa tumors identified on imaging studies as distal lesions/hot spots in higher risk PCa cases, as well as a primary and focal tx for low/moderate risk localized, gland confined PCa.

    Wondering which CK protocol (Gy dosing, fractions) is being used to treat the spot. Also, it would be helpful to understand the rationale in choosing CK vs IG/IMRT to treat the distal tumor and, the TIP protocol (length of time; intermittent; continuous) that your oncologist is recommending. Thanks for any add'l info you might be willing to share.

    All the best and good luck to you both.
  • janekirstine
    janekirstine Member Posts: 24 Member

    Success
    I know a man who has had two tumors removed from his spine using cyberknife, and is going on with his life with hormones with no physical effects.

    Good choice, good luck

    Good PSA News
    Great news for us today! PSA drop after beginning hormone treatment. Is this normal for PSA to drop so quickly? We were under the impression that it took a few months to decrease. Also following strict Mediterranean Diet with no dairy or meat. Very excited about the drop.

    Oct 2011 –- 4.33
    22 Oct 2011 - Started Casodex
    08 Nov 2011 - First Lupron shot

    15 Nov 2011 PSA 0.37

    TIP protocol recommended by our oncologist is continual monitoring and intermittent as needed (those are my lay doctor words). Will see him every four weeks right now.

    Awaiting insurance approval for CK - Still do not know CK protocol (Gy dosing, fractions) that will be used to treat the spot. Another MRI needed.
    J
  • janekirstine
    janekirstine Member Posts: 24 Member
    Cyberknife Dosage
    Husband is receiving Cyberknife on Friday for the identified metastatic tumor on the sacrum.

    Dosage prescribed is 2,000 cGy to the 66% isodose line. Only one treatment required.

    I looked up isodose line since term was new to me:

    During a radiosurgery procedure, the center of the targeted lesion will receive a certain amount of radiation. There will be a spot in the lesion which will receive 100% of the maximum dose. For example, a part near the center of the lesion may receive 20 Gray (a unit of radiation). There will be a curve or surface which will receive 30% or this, and one which will receive 50%, etc. These are known as isodose lines, much like the isothermal lines of temperature on a map of the United States. The 50% isodose line will receive 50% of the maximum dose, or half the dose. In the example above, if the maximum dose is 20 Gray, then the 50% isodose line will receive 10 Gray. http://www.neurosurgerypa.com/glossary/isodose.html
  • VascodaGama
    VascodaGama Member Posts: 3,638 Member

    Cyberknife Dosage
    Husband is receiving Cyberknife on Friday for the identified metastatic tumor on the sacrum.

    Dosage prescribed is 2,000 cGy to the 66% isodose line. Only one treatment required.

    I looked up isodose line since term was new to me:

    During a radiosurgery procedure, the center of the targeted lesion will receive a certain amount of radiation. There will be a spot in the lesion which will receive 100% of the maximum dose. For example, a part near the center of the lesion may receive 20 Gray (a unit of radiation). There will be a curve or surface which will receive 30% or this, and one which will receive 50%, etc. These are known as isodose lines, much like the isothermal lines of temperature on a map of the United States. The 50% isodose line will receive 50% of the maximum dose, or half the dose. In the example above, if the maximum dose is 20 Gray, then the 50% isodose line will receive 10 Gray. http://www.neurosurgerypa.com/glossary/isodose.html

    Good News on the Lower PSA after HT
    Jane

    You surely are handling this recurrence in the rightful way. HT (TIP) will arrest the cancer and CK will treat the lesion in bone. One important aspect of the fast lowering of PSA after starting HT is that the cancer responds well to hormonal manipulation which can assure prolonged periods of control. Some guys get to the 12-15 years mark before starting a second line therapy.

    I recommend you testosterone tests done along with the PSA tests to ascertain of the drug’s effectiveness. The hormonal treatment aims into lowering the testosterone levels in the body (chemo castration) and that causes side effects too. Some guys report mild symptoms but in some they are nasty. You can search the net typing “Hormone therapy side effects in Prostate cancer”, to read details.
    HT also influences bone loss. He may start taking a bisphosphonate (like Zometa) which will help in preventing bone metastases and bone loss (osteoporosis). Your husband could add a bone density scan (DEXA) to his routine check up.

    For better understanding the hormonal treatment and diet, I suggest you to get a copy of the following book (it has help me a lot in understanding HT in my case);
    “Beating Prostate Cancer: Hormonal Therapy & Diet” by Dr. Charles “Snuffy” Myers.

    Hopefully that this bump in your husband’s journey resumes the soonest and that you both get peace of mind.

    Wishing you the best.

    VGama

    Note; For future reference you may be interested in reading these links;
    http://csn.cancer.org/node/227012
    www.youtube.com/watch?feature=player_embedded&v=nDvY7opm3Fs&mid=54
  • mrspjd
    mrspjd Member Posts: 694 Member

    Cyberknife Dosage
    Husband is receiving Cyberknife on Friday for the identified metastatic tumor on the sacrum.

    Dosage prescribed is 2,000 cGy to the 66% isodose line. Only one treatment required.

    I looked up isodose line since term was new to me:

    During a radiosurgery procedure, the center of the targeted lesion will receive a certain amount of radiation. There will be a spot in the lesion which will receive 100% of the maximum dose. For example, a part near the center of the lesion may receive 20 Gray (a unit of radiation). There will be a curve or surface which will receive 30% or this, and one which will receive 50%, etc. These are known as isodose lines, much like the isothermal lines of temperature on a map of the United States. The 50% isodose line will receive 50% of the maximum dose, or half the dose. In the example above, if the maximum dose is 20 Gray, then the 50% isodose line will receive 10 Gray. http://www.neurosurgerypa.com/glossary/isodose.html

    All the best on Friday!
    Might you know if or how the CK/SBRT dosing & protocol that husband is receiving as tx for a bone met would differ from an IG/IMRT dosing & protocol for the same type of bone met tx? How did this info influence your & husband’s decision to choose CK/SBRT vs IMRT to treat the hot spot? Thanks.

    Good luck. I’m looking forward to good news in your future updates!
  • janekirstine
    janekirstine Member Posts: 24 Member
    Hi mrspjd!
    I do not know what the IG/IMRT dosing and protocol would be. From our understanding, the CK/SBRT is a more precise focal method for targeting the hot spot so near the spinal nerves. Doctors used the IG/IMRT on husband for the smaller tumor in the prostate bed with a lower dosage in 38 treatments. IG/IMRT would affect a greater radiation area which be undesirable in his case.

    Thank you for the good wishes. I am a bit nervous about the procedure. J
  • mrspjd
    mrspjd Member Posts: 694 Member

    Hi mrspjd!
    I do not know what the IG/IMRT dosing and protocol would be. From our understanding, the CK/SBRT is a more precise focal method for targeting the hot spot so near the spinal nerves. Doctors used the IG/IMRT on husband for the smaller tumor in the prostate bed with a lower dosage in 38 treatments. IG/IMRT would affect a greater radiation area which be undesirable in his case.

    Thank you for the good wishes. I am a bit nervous about the procedure. J

    Hi Jane,
    I support the CK/SBRT decision you’ve made 100% and believe it will be successful in treating the bone met; however, I don’t necessary agree with it. I’m no expert on RT (far from it!) but, FWIW and IMHO, I believe that any minimal Gray “spillage” outside the tx field from IMRT to the hot spot being treated would be safe and perhaps even beneficial to the adjacent bone area (and/or spine/soft tissue) where current imaging may not indicate micro-mets. Just my 2 cents worth. I do understand than many of these variables are calculated into the dosing plan and radiation field for both types of RT.

    I totally relate to the anxiety and nervousness that you mention. Deep breaths, slowly exhale, mindful meditation…that’s what got me through my DH’s txs…and continues to be helpful while waiting for test results from his on-going PSA blood draws. I recommend you give it a try.

    I’ll be thinking of you both on Friday.
  • janekirstine
    janekirstine Member Posts: 24 Member
    mrspjd said:

    Hi Jane,
    I support the CK/SBRT decision you’ve made 100% and believe it will be successful in treating the bone met; however, I don’t necessary agree with it. I’m no expert on RT (far from it!) but, FWIW and IMHO, I believe that any minimal Gray “spillage” outside the tx field from IMRT to the hot spot being treated would be safe and perhaps even beneficial to the adjacent bone area (and/or spine/soft tissue) where current imaging may not indicate micro-mets. Just my 2 cents worth. I do understand than many of these variables are calculated into the dosing plan and radiation field for both types of RT.

    I totally relate to the anxiety and nervousness that you mention. Deep breaths, slowly exhale, mindful meditation…that’s what got me through my DH’s txs…and continues to be helpful while waiting for test results from his on-going PSA blood draws. I recommend you give it a try.

    I’ll be thinking of you both on Friday.

    Hi mrspjd,
    Thank you for your support. The deep breaths are great. I also go on long walks through the city while husband is in MRI/scan, etc. so I do not have to sit in the waiting room and worry.

    I really appreciate your discussion on the radiation treatments. The more discussion, the more we learn. When the hot spot was first found, our radiation oncologist did not suggest to us that it was treatable. We asked if Cyberknife could target it and he did not know, thus referring us to the CK team. I would have thought that if IG/IMRT was a possibility, the radiation oncologist would have laid out a plan at that time. Long story short, we are in good hands with the CK team.

    Time to plan a vacation! J
  • mrspjd
    mrspjd Member Posts: 694 Member

    Hi mrspjd,
    Thank you for your support. The deep breaths are great. I also go on long walks through the city while husband is in MRI/scan, etc. so I do not have to sit in the waiting room and worry.

    I really appreciate your discussion on the radiation treatments. The more discussion, the more we learn. When the hot spot was first found, our radiation oncologist did not suggest to us that it was treatable. We asked if Cyberknife could target it and he did not know, thus referring us to the CK team. I would have thought that if IG/IMRT was a possibility, the radiation oncologist would have laid out a plan at that time. Long story short, we are in good hands with the CK team.

    Time to plan a vacation! J

    Excellent
    Jane,

    I believe as you do, that you and your DH are in good hands. In addition, you bring up an excellent point that many of us have learned on this PCa journey, in this case, tx options for a bone met with SBRT or IMRT. Unfortunately, a doctor may not initially offer certain options in his/her discussion with the (cancer) patient for a number of different reasons (IMO, none of them good reasons). This is when being an educated patient pays off…when the patient, himself, can bring up other viable options related to dx, staging, testing, txs, recovery, rehab, etc. to discuss with the doctor…and when seeking 2nd & 3rd opinions can lead to new perspectives & opportunities for exploring other viable options/choices. This is the meaning of being your own best advocate as a medical patient. It shouldn’t have to be this way, but it is what it is.

    Walking/exercise is great, although I was always worried about leaving the waiting room/lobby when my DH was in for diagnostic testing, treatments, etc. I’m a believer in Murphy’s Laws and figured that if I left for any period of time (even if the medical team had my cell # and could reach me quickly by phone if need be), that I would receive their call when I was out on the walk at the farthest point away from the medical center, even if that was only 1 block away! Yes, I take worrying seriously and one could even say that I’ve turned worrying into an art form!

    Now, as for that vacation…have you considered Japan? Again, just kidding (or maybe not) and thanks for understanding my sometimes warped sense of humor in another thread.

    Best,

    mrs pjd
  • Kongo
    Kongo Member Posts: 1,166 Member

    Hi mrspjd,
    Thank you for your support. The deep breaths are great. I also go on long walks through the city while husband is in MRI/scan, etc. so I do not have to sit in the waiting room and worry.

    I really appreciate your discussion on the radiation treatments. The more discussion, the more we learn. When the hot spot was first found, our radiation oncologist did not suggest to us that it was treatable. We asked if Cyberknife could target it and he did not know, thus referring us to the CK team. I would have thought that if IG/IMRT was a possibility, the radiation oncologist would have laid out a plan at that time. Long story short, we are in good hands with the CK team.

    Time to plan a vacation! J

    SBRT Vs. IMRT?
    This is more complicated than simply the accuracy of beam placement although SBRT delivered through the CyberKnife system achieves higher accuracy than traditional IMRT because the fiducial placements allow real time tracking of the prostate or tumor movement (in areas where SBRT is used outside the prostate). Traditional IMRT does not do real time adjustments of the radiation beams although newer technologies are incorporating real time tracking so that soon I would expect that IMRT would be as accurate as the CK system.

    Both CK and IMRT are fractionated means of delivering radiation. Both deliver similar radiation coverage plans and both deliver similar total dosages by the end of treatment. Both deliver photon radiation via linear accelerators. In the CK case, the LINAC is mounted on a robot arm which moves about the patient while IMRT is mounted in a stationary frame and the radiation is rotated electronically while the patient lies in a tube. CyberKnife is delivered in four or five hypo-fractionated treatments (sometimes in a single dose for tumors outside the prostate) while IMRT can take as much as 8 weeks or more to deliver the same dosage in fractionated treatment.

    The key difference, in my lay opinion, is not the accuracy or the amount of (as mrspjd calls it) "gray spillage." Both IMRT and CK are highly accurate. The big difference is the reason why SBRT was developed as a means of delivering hypo-fractionated doses in the first place. Since both IMRT and SBRT deliver equivalent total dosages, the big difference is in the amount of radiation delivered in each dose. CK delivers a much higher dosage per session than IMRT.

    The primary reason SBRT is used to treat prostate cancer is that most slow growing prostate cancers have been showN to have a low alpha/beta ratio which means that they are more resistant to the effect of radiation than cancers with a higher alpha/beta ratio. The theory behind delivering a higher dose per fraction has nothing at all to do with convenience and getting the radiation out of the way faster...it's all about delivering more radiation per dose to a type of cancer that is resistant to lesser dosages of fractional radiation. (The alpha/beta ratio is derived from a linear quadratic equation that compares surviving cells as a function of the square of the dosage.)

    The theory behind using hypo-fractionated radiation to treat prostate cancer has been around for more than 50 years. The problem was in developing a delivery system that could apply the necessary dosage safely without risking harm to surrounding tissue and organs. CyberKnife did this when it mounted the linear accelerator to a robotic arm, incorporated real time imaging, and integrated a software program that merged these components to produce real time tracking while delivering radiation.

    As far as radiation spillage being potentially beneficial because it could affect micro clusters or cells outside the targeted area...well, this just doesn't seem to make sense to me since the dosage level would be well below the alpha/beta ration necessary to kill cancer cells. I have never heard of this notion being expressed before in anything I have ever read about radiation. Both CK and IMRT are forms of external radiation which means the photons will travel through the body and adjacent tissue and organs. Since the total dosage is pretty much the same, the amount of radiation traveling through these areas is going to be about the same whether or not it is delivered by CK or IMRT. The beneficial effect is achieved these beams overlap in the area of the tumor according to the radiation plan not in some adjacent area that might pick up some small amount of collateral radiation.

    K
  • Swingshiftworker
    Swingshiftworker Member Posts: 1,017 Member
    Kongo said:

    SBRT Vs. IMRT?
    This is more complicated than simply the accuracy of beam placement although SBRT delivered through the CyberKnife system achieves higher accuracy than traditional IMRT because the fiducial placements allow real time tracking of the prostate or tumor movement (in areas where SBRT is used outside the prostate). Traditional IMRT does not do real time adjustments of the radiation beams although newer technologies are incorporating real time tracking so that soon I would expect that IMRT would be as accurate as the CK system.

    Both CK and IMRT are fractionated means of delivering radiation. Both deliver similar radiation coverage plans and both deliver similar total dosages by the end of treatment. Both deliver photon radiation via linear accelerators. In the CK case, the LINAC is mounted on a robot arm which moves about the patient while IMRT is mounted in a stationary frame and the radiation is rotated electronically while the patient lies in a tube. CyberKnife is delivered in four or five hypo-fractionated treatments (sometimes in a single dose for tumors outside the prostate) while IMRT can take as much as 8 weeks or more to deliver the same dosage in fractionated treatment.

    The key difference, in my lay opinion, is not the accuracy or the amount of (as mrspjd calls it) "gray spillage." Both IMRT and CK are highly accurate. The big difference is the reason why SBRT was developed as a means of delivering hypo-fractionated doses in the first place. Since both IMRT and SBRT deliver equivalent total dosages, the big difference is in the amount of radiation delivered in each dose. CK delivers a much higher dosage per session than IMRT.

    The primary reason SBRT is used to treat prostate cancer is that most slow growing prostate cancers have been showN to have a low alpha/beta ratio which means that they are more resistant to the effect of radiation than cancers with a higher alpha/beta ratio. The theory behind delivering a higher dose per fraction has nothing at all to do with convenience and getting the radiation out of the way faster...it's all about delivering more radiation per dose to a type of cancer that is resistant to lesser dosages of fractional radiation. (The alpha/beta ratio is derived from a linear quadratic equation that compares surviving cells as a function of the square of the dosage.)

    The theory behind using hypo-fractionated radiation to treat prostate cancer has been around for more than 50 years. The problem was in developing a delivery system that could apply the necessary dosage safely without risking harm to surrounding tissue and organs. CyberKnife did this when it mounted the linear accelerator to a robotic arm, incorporated real time imaging, and integrated a software program that merged these components to produce real time tracking while delivering radiation.

    As far as radiation spillage being potentially beneficial because it could affect micro clusters or cells outside the targeted area...well, this just doesn't seem to make sense to me since the dosage level would be well below the alpha/beta ration necessary to kill cancer cells. I have never heard of this notion being expressed before in anything I have ever read about radiation. Both CK and IMRT are forms of external radiation which means the photons will travel through the body and adjacent tissue and organs. Since the total dosage is pretty much the same, the amount of radiation traveling through these areas is going to be about the same whether or not it is delivered by CK or IMRT. The beneficial effect is achieved these beams overlap in the area of the tumor according to the radiation plan not in some adjacent area that might pick up some small amount of collateral radiation.

    K

    Spillover
    FWIW, I had the same reaction you did to mrspjd's speculation re: the potential benefits of radiation spillover using IMRT but didn't feel I had sufficient knowledge to dispute the suggestion. Thanks for clarifying that point for us.
  • Kongo
    Kongo Member Posts: 1,166 Member

    Spillover
    FWIW, I had the same reaction you did to mrspjd's speculation re: the potential benefits of radiation spillover using IMRT but didn't feel I had sufficient knowledge to dispute the suggestion. Thanks for clarifying that point for us.

    Radiation
    It may be a moot point in this case as Jane's husband only had a single session. In this case, I don't think it really makes much difference whether it was SBRT or IMRT and the radiation to surrounding tissue would likely be the same as both systems would deliver highly conformal dosages to the targeted area. Another thing that may be moot here is whether or not they had to worry about real time movement of the remote tumor. I suspect that Jane's husband could be immobilized for a single session but (thus negating one of the big advantages of CK) but I don't think we know enough about the circumstances here.

    Frankly, I don't know enough about all the advances in IMRT to know if that equipment is optimized to deliver the necessary dosage in a single session like the CK equipment could do. It doesn't look like there was ever a comparison done between the two methods for addressing this remote tumor...instead it seems like they asked for CK and went down that path.

    In any event, the end results between CK and IMRT are pretty small and will likely get to be closer as advances are made in the targeting techniques used with the IMRT system.

    K
  • mrspjd
    mrspjd Member Posts: 694 Member
    Kongo said:

    SBRT Vs. IMRT?
    This is more complicated than simply the accuracy of beam placement although SBRT delivered through the CyberKnife system achieves higher accuracy than traditional IMRT because the fiducial placements allow real time tracking of the prostate or tumor movement (in areas where SBRT is used outside the prostate). Traditional IMRT does not do real time adjustments of the radiation beams although newer technologies are incorporating real time tracking so that soon I would expect that IMRT would be as accurate as the CK system.

    Both CK and IMRT are fractionated means of delivering radiation. Both deliver similar radiation coverage plans and both deliver similar total dosages by the end of treatment. Both deliver photon radiation via linear accelerators. In the CK case, the LINAC is mounted on a robot arm which moves about the patient while IMRT is mounted in a stationary frame and the radiation is rotated electronically while the patient lies in a tube. CyberKnife is delivered in four or five hypo-fractionated treatments (sometimes in a single dose for tumors outside the prostate) while IMRT can take as much as 8 weeks or more to deliver the same dosage in fractionated treatment.

    The key difference, in my lay opinion, is not the accuracy or the amount of (as mrspjd calls it) "gray spillage." Both IMRT and CK are highly accurate. The big difference is the reason why SBRT was developed as a means of delivering hypo-fractionated doses in the first place. Since both IMRT and SBRT deliver equivalent total dosages, the big difference is in the amount of radiation delivered in each dose. CK delivers a much higher dosage per session than IMRT.

    The primary reason SBRT is used to treat prostate cancer is that most slow growing prostate cancers have been showN to have a low alpha/beta ratio which means that they are more resistant to the effect of radiation than cancers with a higher alpha/beta ratio. The theory behind delivering a higher dose per fraction has nothing at all to do with convenience and getting the radiation out of the way faster...it's all about delivering more radiation per dose to a type of cancer that is resistant to lesser dosages of fractional radiation. (The alpha/beta ratio is derived from a linear quadratic equation that compares surviving cells as a function of the square of the dosage.)

    The theory behind using hypo-fractionated radiation to treat prostate cancer has been around for more than 50 years. The problem was in developing a delivery system that could apply the necessary dosage safely without risking harm to surrounding tissue and organs. CyberKnife did this when it mounted the linear accelerator to a robotic arm, incorporated real time imaging, and integrated a software program that merged these components to produce real time tracking while delivering radiation.

    As far as radiation spillage being potentially beneficial because it could affect micro clusters or cells outside the targeted area...well, this just doesn't seem to make sense to me since the dosage level would be well below the alpha/beta ration necessary to kill cancer cells. I have never heard of this notion being expressed before in anything I have ever read about radiation. Both CK and IMRT are forms of external radiation which means the photons will travel through the body and adjacent tissue and organs. Since the total dosage is pretty much the same, the amount of radiation traveling through these areas is going to be about the same whether or not it is delivered by CK or IMRT. The beneficial effect is achieved these beams overlap in the area of the tumor according to the radiation plan not in some adjacent area that might pick up some small amount of collateral radiation.

    K

    Isn’t scientific/medical knowledge a wonderful thing!
    Isn’t scientific/medical knowledge a wonderful thing! I’ve heard that IG/IMRT has a long history of being used to successfully tx PCa bone mets. I realize that SBRT/CK has been used to treat certain hard to reach inoperable tumors in the body; however, I’ve never seen any clinical studies pertaining to tx of bone mets specifically from PCa (not that it hasn’t been done). I’m sure bone mets from other types of cancers have been treated with SBRT but, I wonder if you might cite some clinical studies where SBRT/CK was used in the treatment of bone mets SPECIFICALLY in PCa patients and how the rates of success/failure compare to that of tx for PCa bone mets with IG/IMRT and what the different dosing protocols are for each RT modality?

    BTW, the newer IG/IMRT medical equipment/technology track in real time with the ability to shut down for movement, use fiducial tracking, and are also able to deliver SBRT. The well known & respected Dr. Christopher King (formerly of Stanford who was a pioneer in the use of SBRT/CK for treating low risk organ confined PCa) is currently using a different manufacturer’s brand of RT technology (NOT Accuray’s CK) to provide SBRT to his patients in So. California.

    mrs pjd
  • Kongo
    Kongo Member Posts: 1,166 Member
    mrspjd said:

    Isn’t scientific/medical knowledge a wonderful thing!
    Isn’t scientific/medical knowledge a wonderful thing! I’ve heard that IG/IMRT has a long history of being used to successfully tx PCa bone mets. I realize that SBRT/CK has been used to treat certain hard to reach inoperable tumors in the body; however, I’ve never seen any clinical studies pertaining to tx of bone mets specifically from PCa (not that it hasn’t been done). I’m sure bone mets from other types of cancers have been treated with SBRT but, I wonder if you might cite some clinical studies where SBRT/CK was used in the treatment of bone mets SPECIFICALLY in PCa patients and how the rates of success/failure compare to that of tx for PCa bone mets with IG/IMRT and what the different dosing protocols are for each RT modality?

    BTW, the newer IG/IMRT medical equipment/technology track in real time with the ability to shut down for movement, use fiducial tracking, and are also able to deliver SBRT. The well known & respected Dr. Christopher King (formerly of Stanford who was a pioneer in the use of SBRT/CK for treating low risk organ confined PCa) is currently using a different manufacturer’s brand of RT technology (NOT Accuray’s CK) to provide SBRT to his patients in So. California.

    mrs pjd

    Studies?
    As you well know, radiation treatment for bone mets is usually considered to be pallative in that it can reduce associated pain and frequently prolong the life of the patient. While there may be some exceptional cases where treatment is intended to be curative I am not aware of any studies which compared the difference between IMRT and SBRT. I am not sure what the point of such a study might show since it is my understanding that most bone mets are treated in a single session and in the case of IMRT or SBRT the same total dosage would probably be the same.

    It is my understanding that when Dr. King left Stanford for UCLA he transitioned to the Varian RapidArc system which was already at UCLA. The Varian system was one of the ones I researched and consulted with after my initial diagnosis. It is designed to deliver various types of radiation such as IMRT, IGRT, as well as SBRT and from that perspective, it probably more economical for institutions with a need to treat many different types of cancer with various radiation methods.
  • mrspjd
    mrspjd Member Posts: 694 Member
    Kongo said:

    Studies?
    As you well know, radiation treatment for bone mets is usually considered to be pallative in that it can reduce associated pain and frequently prolong the life of the patient. While there may be some exceptional cases where treatment is intended to be curative I am not aware of any studies which compared the difference between IMRT and SBRT. I am not sure what the point of such a study might show since it is my understanding that most bone mets are treated in a single session and in the case of IMRT or SBRT the same total dosage would probably be the same.

    It is my understanding that when Dr. King left Stanford for UCLA he transitioned to the Varian RapidArc system which was already at UCLA. The Varian system was one of the ones I researched and consulted with after my initial diagnosis. It is designed to deliver various types of radiation such as IMRT, IGRT, as well as SBRT and from that perspective, it probably more economical for institutions with a need to treat many different types of cancer with various radiation methods.

    Yes, studies, as in clinical studies
    Yes, studies, as in clinical studies, as you well know. In the case of Jane’s DH, I seem to recall that a rising PSA following RP and SRT lead to the discovery of the bone met on a fluoride PET scan, and that no or little pain was associated with the bone met. I’m sure Jane will clarify this info. The type of intense severe debilitating bone pain often common & found in advanced stage PCa (and untreated advanced cases) where bone mets may have spread throughout & disease is systemic, are the type of bone mets that may be treated palliatively with RT and/or new bone drugs such as Xgeva and ADT drugs such as Zytiga.

    I would hope that J & T are going for a curative treatment not a palliative tx and have carefully chosen a bone met tx with a history of success in the tx of PCa bone mets, and one with a proven radiation dosing plan for PCa bone met tx, that will zap (a non-technical term, in case you were wondering) the hot spot/bone met that has been identified on PET imagining. In concert with ADT, I believe that J & T have made a well-informed choice and will be successful.

    A PCa tumor is still a PCa tumor, whether it’s on the bone as a result of a bone met from PCa cancer or whether it’s in the prostate from PCa. Systemic disease is another matter entirely and that is where ADT protocols may also be beneficial to the patient. If RT tx (IMRT or SBRT) to one (or less than 5) PCa bone met tumor(s) were considered palliative as claimed pertaining to a bone met, then what future hope is there for any patient treated for PCa tumor(s), no matter the location of the tumor or the treatment modality? IMO, for higher risk tumors or where disease beyond the tumor or gland may be likely, tx of less Gy spread over a longer length of time with a higher total Gy may be superior to a tx consisting of less fractions over several days at higher dosing, convenience factor or not, where total Gy is less.

    Briefly, Ogliometastatic disease & PCa suggests that radiation directed to bone mets (5 or less) as well as the pelvic bed can lead to long term success. This info may pertain to J & T's case. Dr. Charles "Snuffy" Myers, the well known PCa physician (also a PCa survivor) and one of the leading doctors/medical authorities on advanced prostate cancer has a video presentation on ogliometastatic disease: http://askdrmyers.wordpress.com/category/ogliometastatic-disease/

    My brother, also diagnosed with PCa, is a patient of Dr. Kings and was treated with SBRT @ UCLA for low risk gland confined PCa. I have respect for both SBRT and IG/IMRT. I can assure you that UCLA, a world class medical & cancer tx center, has spared no expense in purchasing the latest, most up to date medical technology equipment available today (imaging, tx, RT etc) and in creating a "brain trust" of the most esteemed and highly regarded world class medical professionals in the field of cancer tx and research, and more specifically in the realm of PCa. I have no doubt that if the UCLA "powers that be" felt that Accuray's brand of CK was significantly superior in tx outcomes or offered any add'l technology over the state of the art medical technology that already exists at UCLA, UCLA would most definitely offer it.

    J & T have made their decision and have gone forward with the treatment today. I support their decision 100%. IMHO, that is what is most important on this thread. I sincerely wish them success in this war on PCa.

    mrs pjd
  • Kongo
    Kongo Member Posts: 1,166 Member
    mrspjd said:

    Yes, studies, as in clinical studies
    Yes, studies, as in clinical studies, as you well know. In the case of Jane’s DH, I seem to recall that a rising PSA following RP and SRT lead to the discovery of the bone met on a fluoride PET scan, and that no or little pain was associated with the bone met. I’m sure Jane will clarify this info. The type of intense severe debilitating bone pain often common & found in advanced stage PCa (and untreated advanced cases) where bone mets may have spread throughout & disease is systemic, are the type of bone mets that may be treated palliatively with RT and/or new bone drugs such as Xgeva and ADT drugs such as Zytiga.

    I would hope that J & T are going for a curative treatment not a palliative tx and have carefully chosen a bone met tx with a history of success in the tx of PCa bone mets, and one with a proven radiation dosing plan for PCa bone met tx, that will zap (a non-technical term, in case you were wondering) the hot spot/bone met that has been identified on PET imagining. In concert with ADT, I believe that J & T have made a well-informed choice and will be successful.

    A PCa tumor is still a PCa tumor, whether it’s on the bone as a result of a bone met from PCa cancer or whether it’s in the prostate from PCa. Systemic disease is another matter entirely and that is where ADT protocols may also be beneficial to the patient. If RT tx (IMRT or SBRT) to one (or less than 5) PCa bone met tumor(s) were considered palliative as claimed pertaining to a bone met, then what future hope is there for any patient treated for PCa tumor(s), no matter the location of the tumor or the treatment modality? IMO, for higher risk tumors or where disease beyond the tumor or gland may be likely, tx of less Gy spread over a longer length of time with a higher total Gy may be superior to a tx consisting of less fractions over several days at higher dosing, convenience factor or not, where total Gy is less.

    Briefly, Ogliometastatic disease & PCa suggests that radiation directed to bone mets (5 or less) as well as the pelvic bed can lead to long term success. This info may pertain to J & T's case. Dr. Charles "Snuffy" Myers, the well known PCa physician (also a PCa survivor) and one of the leading doctors/medical authorities on advanced prostate cancer has a video presentation on ogliometastatic disease: http://askdrmyers.wordpress.com/category/ogliometastatic-disease/

    My brother, also diagnosed with PCa, is a patient of Dr. Kings and was treated with SBRT @ UCLA for low risk gland confined PCa. I have respect for both SBRT and IG/IMRT. I can assure you that UCLA, a world class medical & cancer tx center, has spared no expense in purchasing the latest, most up to date medical technology equipment available today (imaging, tx, RT etc) and in creating a "brain trust" of the most esteemed and highly regarded world class medical professionals in the field of cancer tx and research, and more specifically in the realm of PCa. I have no doubt that if the UCLA "powers that be" felt that Accuray's brand of CK was significantly superior in tx outcomes or offered any add'l technology over the state of the art medical technology that already exists at UCLA, UCLA would most definitely offer it.

    J & T have made their decision and have gone forward with the treatment today. I support their decision 100%. IMHO, that is what is most important on this thread. I sincerely wish them success in this war on PCa.

    mrs pjd

    I share your hope that Jane and her husband find a cure for this situation. Were I in his shoes I would be doing exactly what they are and pursing an aggressive approach to treat the cancer that they could see. My earlier comments reflect my general understanding that metastatic prostate cancer gradually spreads to other organs and that the average time it takes for it to be visible in the bones is about ten years after it leaves the prostate. The overwhelming number of radiation treatments to the bone is to address the pain and discomfort that accompanies this advanced form of prostate cancer and are palliative in nature, not curative.

    The concept of ogliometastatic (as opposed to polymetastatic) prostate cancer is a relatively new hypothesis and for the sake of Jane and her husband certainly hope it is relevant to their situation. (see http://www.ncbi.nlm.nih.gov/pubmed/14697414 and http://www.nature.com/nrclinonc/journal/v8/n6/pdf/nrclinonc.2011.44.pdf?WT.ec_id=NRCLINONC-201106).

    My overall opinion about prostate cancer metastasis is rather pessimistic. While I am certainly no expert on the biology of metastasizing prostate cancer cells, from the many books I have read my impression is that once the cancer escapes the prostate then it is probably going to continue to spread. If that occurs, hopefully it is detected very early and contained nearby in the prostate bed where it can be addressed with radiation treatment. If prostate cancer recurs after several years, it seems to me that these cancer cells have been kicking about the blood stream and lymph system for some time and when the PSA starts to rise then they’ve established themselves in a high enough concentration to be worrisome. Although anything is possible (and I would dearly like to be proven wrong here), it just seems unlikely to me that these wandering prostate cancer cells would only exist in a few locations. If that does happen, it seems to me that an ogliometastatic state would only exist for a relatively short period of time and that much is dependent upon the characteristics of the cancer at initial diagnosis and the amount of time between initial diagnosis and the discovery of distant metastasis.

    Every day I am thankful that I had prostate cancer and not some other more virulent form cancer. In most cases (certainly not all) prostate cancer is so slow growing that, depending on your age at diagnosis, doing nothing or pursuing some other treatment will either eliminate a locally contained tumor or at least kick the inexorable progress down the road far enough that you end up expiring of something other than prostate cancer. For the overwhelming majority of prostate cancer patients, that is exactly what happens.

    I do question your opinion that “for higher risk tumors or where disease beyond the tumor or gland may be likely, tx of less Gy spread over a longer length of time with a higher total Gy may be superior to a tx consisting of less fractions over several days at higher dosing, convenience factor or not, where total Gy is less.” As you point out, prostate cancer is prostate cancer regardless of where it is located and this theory of yours tends to fly in the face of why recent advances in radiation are moving toward higher doses of radiation because of the impact of the alpha/beta ratio on the treatment of prostate cancer. In any event, all grays are not equal, and the Biological Equivalent Dose (BED) delivered by the two methods is virtually identical although the grays vary dramatically. Even IMRT, for example, is moving toward higher doses and fewer fractions as improvements are made to enable equipment to accurately deliver the higher doses of radiation and avoid potential damage to surrounding tissue and organs.

    I need no assurances about the quality of the UCLA Medical Center. I am quite familiar with its capabilities and world-renowned reputation and have actually spent quite a lot of time in various facilities there while my son was an undergraduate. Dr. King is a wonderful researcher and pioneering physician and it must be comforting to know your brother is in such good care. I am somewhat familiar with the Varian equipment used at UCLA and am sure it is state-of-the art, as is the CK equipment in use at Georgetown, Stanford, Harvard, and other world-class medical institutions. It is exciting to me that so many pioneering medical centers are exploring SBRT with respect to prostate cancer and in my opinion, the more varied the equipment at these many centers the faster further advances will be forthcoming. There are, of course, technical differences between the two systems and from what I understand they mostly have to do with how the imaging is performed with respect to fiducial adjustment. Dr. King would say the Varian equipment delivers a higher degree of conformal beam structure. Others might disagree on these technical points but I know for sure that the Varian system delivers SBRT faster than CK. Actually I don’t think it matters much which equipment is used. Each has certain advantages and disadvantages. To me, the important thing amongst all the SBRT delivery systems is the hypo-fractionated dosage plan.

    Regarding studies. I don’t expect to ever see a clinical trial or study that puts different radiation types head-to-head. It would be enormously expensive and given the pace of advancements likely obsolete before a reasonable amount of time could pass. And anyway, who who would agree to let someone else make treatment choices for them? What we have instead is a bunch of papers where the results of one study are compared against the results of another study. Each of these studies apply different methods of statistical analysis, data normalization, cohort selection, equipment used, and on and on. I think this is one of the reasons why we end up arguing so much about one study over another. You can almost believe anything you want (and some people do). Dr. Katz, who recently published a paper about his 5-year CyberKnife results, indicated that he would soon release a paper comparing CK/SBRT to IMRT. I’ll reserve judgment until I read his paper but in any case it will not have been a head-to-head comparison but only a comparison of individual study results.
  • janekirstine
    janekirstine Member Posts: 24 Member
    mrspjd said:

    Yes, studies, as in clinical studies
    Yes, studies, as in clinical studies, as you well know. In the case of Jane’s DH, I seem to recall that a rising PSA following RP and SRT lead to the discovery of the bone met on a fluoride PET scan, and that no or little pain was associated with the bone met. I’m sure Jane will clarify this info. The type of intense severe debilitating bone pain often common & found in advanced stage PCa (and untreated advanced cases) where bone mets may have spread throughout & disease is systemic, are the type of bone mets that may be treated palliatively with RT and/or new bone drugs such as Xgeva and ADT drugs such as Zytiga.

    I would hope that J & T are going for a curative treatment not a palliative tx and have carefully chosen a bone met tx with a history of success in the tx of PCa bone mets, and one with a proven radiation dosing plan for PCa bone met tx, that will zap (a non-technical term, in case you were wondering) the hot spot/bone met that has been identified on PET imagining. In concert with ADT, I believe that J & T have made a well-informed choice and will be successful.

    A PCa tumor is still a PCa tumor, whether it’s on the bone as a result of a bone met from PCa cancer or whether it’s in the prostate from PCa. Systemic disease is another matter entirely and that is where ADT protocols may also be beneficial to the patient. If RT tx (IMRT or SBRT) to one (or less than 5) PCa bone met tumor(s) were considered palliative as claimed pertaining to a bone met, then what future hope is there for any patient treated for PCa tumor(s), no matter the location of the tumor or the treatment modality? IMO, for higher risk tumors or where disease beyond the tumor or gland may be likely, tx of less Gy spread over a longer length of time with a higher total Gy may be superior to a tx consisting of less fractions over several days at higher dosing, convenience factor or not, where total Gy is less.

    Briefly, Ogliometastatic disease & PCa suggests that radiation directed to bone mets (5 or less) as well as the pelvic bed can lead to long term success. This info may pertain to J & T's case. Dr. Charles "Snuffy" Myers, the well known PCa physician (also a PCa survivor) and one of the leading doctors/medical authorities on advanced prostate cancer has a video presentation on ogliometastatic disease: http://askdrmyers.wordpress.com/category/ogliometastatic-disease/

    My brother, also diagnosed with PCa, is a patient of Dr. Kings and was treated with SBRT @ UCLA for low risk gland confined PCa. I have respect for both SBRT and IG/IMRT. I can assure you that UCLA, a world class medical & cancer tx center, has spared no expense in purchasing the latest, most up to date medical technology equipment available today (imaging, tx, RT etc) and in creating a "brain trust" of the most esteemed and highly regarded world class medical professionals in the field of cancer tx and research, and more specifically in the realm of PCa. I have no doubt that if the UCLA "powers that be" felt that Accuray's brand of CK was significantly superior in tx outcomes or offered any add'l technology over the state of the art medical technology that already exists at UCLA, UCLA would most definitely offer it.

    J & T have made their decision and have gone forward with the treatment today. I support their decision 100%. IMHO, that is what is most important on this thread. I sincerely wish them success in this war on PCa.

    mrs pjd

    Successful Day
    We are glad that we could stimulate this great conversation on radiation therapy. I will have to digest it all tomorrow.

    CK procedure went completely problem free today, and I was so happy to see my husband walk out of the clinic. He promised to write up about the procedure for those interested. A follow up MRI is scheduled in January to track CK success in destroying the tumor. We also see the medical oncologist this month on hormone therapy progress. PSA fell from 4.33 to 0.37 last month (November 15 results) after just starting HT. So far, no problems or adverse reactions from the Casodex and Lupron.

    I shared the story of VascodaGama’s Japan vacation and his 0.02 ng/ml PSA with my husband during the drive today. He exclaimed that we just have to go to Chernobyl for the cure. I thought Japan sounded spectacular.

    Glad day is winding to an end. Best to all, J
  • mrspjd
    mrspjd Member Posts: 694 Member

    Successful Day
    We are glad that we could stimulate this great conversation on radiation therapy. I will have to digest it all tomorrow.

    CK procedure went completely problem free today, and I was so happy to see my husband walk out of the clinic. He promised to write up about the procedure for those interested. A follow up MRI is scheduled in January to track CK success in destroying the tumor. We also see the medical oncologist this month on hormone therapy progress. PSA fell from 4.33 to 0.37 last month (November 15 results) after just starting HT. So far, no problems or adverse reactions from the Casodex and Lupron.

    I shared the story of VascodaGama’s Japan vacation and his 0.02 ng/ml PSA with my husband during the drive today. He exclaimed that we just have to go to Chernobyl for the cure. I thought Japan sounded spectacular.

    Glad day is winding to an end. Best to all, J

    Chernobyl...LOL...
    But Japan sounds best. Glad all went well. FYI, my husband was on ADT3 including Lupron & Casodex, had no major problems and tolerated the drugs well.

    I look forward to your updates and reports of good news and success! Re Medical Tourism (the new meaning), perhaps PCa patients can get a group discount ;)