From England:"....Avastin,Erbitux and Vectibix will not be routinely available on the NHS
Comments
-
BlakeBuckwirth said:Up to, or Median?
What John posted:
"If a drug might extend life by up to 3.5 months..."
From the article:
"...the median overall survival for patients with the normal, or wild-type, version of a gene called KRAS was 23.5 months compared with 20 months on chemotherapy alone."
The difference is crucial. It means that 50% of the patients in the trial lived LONGER than 23.5 months (the 3.5 month gain you note), in fact, many of them are probably still alive today.
Please John, take a moment and read up on what Median means.
I swore I would ignore your condescending remarks, however...
Re:
"the median overall survival for patients with the normal,
or wild-type, version of a gene called KRAS was
23.5 months, compared with 20 months on chemotherapy alone."
Please understand that the survival rate without the drug, versus
the survival rate with the drug, remains; the same; it does not
change the overall statistics. The drug only adds up to a specific
percentage, regardless what the "median" is.
Example:
10 months without, 13.5 months with.
40 months without, 43.5 with
It was found that the extension of life by up to 3.5 months is not
worth the expense, especially when an individual that is more prone
to survival may die from lack of financial support for treatment,
while the money is spent trying to add "up to" a few months of life
for another individual.
The public would be better off fighting for improved drugs from the
industry, instead of acting like drugs are some sort of a religious
experience that cannot be denounced.
The belief that only one thing can save one's life, when the facts are
so blatant that it cannot, astonishes me. Where has common sense
gone to?
Best hopes for better health,
John0 -
making progress despite cost containment
Many of us here are grappling with various kinds of stage IV, whether as patient or support team. Once someone finds a useful therapy, personal or perceived risks makes it difficult for the patient to justify a change until that therapy cures, fails, or becomes unavailable.
Today's -ib's and ab's nuke a molecular pathway with some strange toxicities. Other alternatives attack multiple pathways and add whole mechanisms with less toxic, non-toxic and even health promoting substances.
The literature that I've worked with implies expanded surgical possiblities for more of today's stage IV "inoperables" with inexpensive generic formulas and less chemo sickness by radically reducing metastasis before, during and after surgery. This potentially means fewer refusals, less treatment delay, less begging of doctors and administrators, and lots more chances.
I'm hallucinating?
With generics and supplements, my wife went from "inoperable" (refusals) to surgery on chemo(!) and out the door in less time than many people could file an insurance appeal for funding. Excised for a fraction of the cost of a single cycle of patent medicine. Also she healed up fast without any chemo sickness. All despite being laughed at and lectured by a pharm pushing oncologist that expected my wife to take a beating and fail the chemo anyway.
Been there, done that.0 -
John,John23 said:Blake
I swore I would ignore your condescending remarks, however...
Re:
"the median overall survival for patients with the normal,
or wild-type, version of a gene called KRAS was
23.5 months, compared with 20 months on chemotherapy alone."
Please understand that the survival rate without the drug, versus
the survival rate with the drug, remains; the same; it does not
change the overall statistics. The drug only adds up to a specific
percentage, regardless what the "median" is.
Example:
10 months without, 13.5 months with.
40 months without, 43.5 with
It was found that the extension of life by up to 3.5 months is not
worth the expense, especially when an individual that is more prone
to survival may die from lack of financial support for treatment,
while the money is spent trying to add "up to" a few months of life
for another individual.
The public would be better off fighting for improved drugs from the
industry, instead of acting like drugs are some sort of a religious
experience that cannot be denounced.
The belief that only one thing can save one's life, when the facts are
so blatant that it cannot, astonishes me. Where has common sense
gone to?
Best hopes for better health,
JohnPlease understand that the survival rate without the drug, versus
the survival rate with the drug, remains; the same; it does not
change the overall statistics. The drug only adds up to a specific
percentage, regardless what the "median" is.No, both the 20 month and the 3.5 month numbers are medians, and they are not absolutes. On a side note, without the one the other has no meaning, so when I pointed out that this represents an 18% increase in survival time that number should hold for any group that repeats the trial.
So that everyone can better understand the statistics, here are some excerpts of Stephen Jay Gould (SJG) explaining Mean/Median and Cancer Stats, along with some comments by me:
Consider the standard example of stretching the truth with numbers - a case quite relevant to my story. Statistics recognizes different measures of an "average," or central tendency. The mean is our usual concept of an overall average - add up the items and divide them by the number of sharers (100 candy bars collected for five kids next Halloween will yield 20 for each in a just world). The median, a different measure of central tendency, is the half-way point. If I line up five kids by height, the median child is shorter than two and taller than the other two (who might have trouble getting their mean share of the candy). A politician in power might say with pride, "The mean income of our citizens is $15,000 per year." The leader of the opposition might retort, "But half our citizens make less than $10,000 per year." Both are right, but neither cites a statistic with impassive objectivity. The first invokes a mean, the second a median. (Means are higher than medians in such cases because one millionaire may outweigh hundreds of poor people in setting a mean; but he can balance only one mendicant in calculating a median).
The above shows how the numbers are different. Now, time for a bit of back story:
At the age of 41, Mr. Gould was diagnosed with Mesothelioma, a disease which (in 1982) had a median survival time from diagnoses of eight months. Being a scientist, and a statistician, he dug into those numbers to see what they meant for him:
SJG:
The problem may be briefly stated: What does "median mortality of eight months" signify in our vernacular? I suspect that most people, without training in statistics, would read such a statement as "I will probably be dead in eight months" - the very conclusion that must be avoided, since it isn't so...
When I learned about the eight-month median, my first intellectual reaction was: fine, half the people will live longer; now what are my chances of being in that half. I read for a furious and nervous hour and concluded, with relief: damned good. I possessed every one of the characteristics conferring a probability of longer life: I was young; my disease had been recognized in a relatively early stage; I would receive the nation's best medical treatment; I had the world to live for; I knew how to read the data properly and not despair.
I will take a moment and comment here. My plea to you to better understand the use of Median is not meant to be condescending, it is just that we have had this conversation multiple times, and the misreading of the data can, as Mr Gould puts it, lead to despair where there should be hope.
SJG:
...I immediately recognized that the distribution of variation about the eight-month median would almost surely be what statisticians call "right skewed." (In a symmetrical distribution, the profile of variation to the left of the central tendency is a mirror image of variation to the right. In skewed distributions, variation to one side of the central tendency is more stretched out - left skewed if extended to the left, right skewed if stretched out to the right.) The distribution of variation had to be right skewed, I reasoned. After all, the left of the distribution contains an irrevocable lower boundary of zero (since mesothelioma can only be identified at death or before). Thus, there isn't much room for the distribution's lower (or left) half - it must be scrunched up between zero and eight months. But the upper (or right) half can extend out for years and years, even if nobody ultimately survives. The distribution must be right skewed, and I needed to know how long the extended tail ran - for I had already concluded that my favorable profile made me a good candidate for that part of the curve.
Another pause to point out that, as a group, the members of this forum are overwhelmingly right skewed. The median age at diagnoses for CRC is 74 years old, and the very nature of an electronic forum at this point in our history trends our median age much lower (on a guess I would say it is between 50 and 55). That very youth helps us withstand our treatments, keep our blood counts up, and means our bodies are better able to defend themselves from the spread of the cancer (better than someone who is older than 74 anyway). There is also a very strong will to survive among those participating here, much stronger than the general population. So, we, as a group, are strongly right skewed.
The distribution was indeed, strongly right skewed, with a long tail (however small) that extended for several years above the eight month median. I saw no reason why I shouldn't be in that small tail, and I breathed a very long sigh of relief. My technical knowledge had helped. I had read the graph correctly. I had asked the right question and found the answers. I had obtained, in all probability, the most precious of all possible gifts in the circumstances - substantial time. I didn't have to stop and immediately follow Isaiah's injunction to Hezekiah - set thine house in order for thou shalt die, and not live. I would have time to think, to plan, and to fight.
Gould died on May 20, 2002 from a metastatic adenocarcinoma of the lung, a full twenty years after the initial diagnoses, and of a completely unrelated cancer.
Hopefully this helps in your understanding of the numbers, and I hope it also helps you understand why I respond to you when you misinterpret the data so glaringly (up to 3.5 months can be a very scary statement to those on this treatment and dealing with this disease).
The issue of payment by Britain's National Health of course is the subject of this posting, and if I lived in the UK I would take a further interest in the politics, both budgetary and political, involved. However, as Sonia and Pepe point out, we do not fully appreciate that systems complexities and it is not our battle. In the US the use of these drugs to fight CRC is not up for debate, and probably will not be in our lifetimes...
As always John, best of health to you. In many ways we disagree, but your story is inspirational to me and I mean you no insult (even when you end your bits implying that I have no common sense, or that I have not done my research, or that I have some monolithic view supporting chemotherapy in all its uses, all of which are wrong, and all of which could be considered condescending). Thank you also for those messages where we have discussed areas of common concern and where you aided both my spirit and my health.
Blake0 -
saying vs showingBuckwirth said:John,
Please understand that the survival rate without the drug, versus
the survival rate with the drug, remains; the same; it does not
change the overall statistics. The drug only adds up to a specific
percentage, regardless what the "median" is.No, both the 20 month and the 3.5 month numbers are medians, and they are not absolutes. On a side note, without the one the other has no meaning, so when I pointed out that this represents an 18% increase in survival time that number should hold for any group that repeats the trial.
So that everyone can better understand the statistics, here are some excerpts of Stephen Jay Gould (SJG) explaining Mean/Median and Cancer Stats, along with some comments by me:
Consider the standard example of stretching the truth with numbers - a case quite relevant to my story. Statistics recognizes different measures of an "average," or central tendency. The mean is our usual concept of an overall average - add up the items and divide them by the number of sharers (100 candy bars collected for five kids next Halloween will yield 20 for each in a just world). The median, a different measure of central tendency, is the half-way point. If I line up five kids by height, the median child is shorter than two and taller than the other two (who might have trouble getting their mean share of the candy). A politician in power might say with pride, "The mean income of our citizens is $15,000 per year." The leader of the opposition might retort, "But half our citizens make less than $10,000 per year." Both are right, but neither cites a statistic with impassive objectivity. The first invokes a mean, the second a median. (Means are higher than medians in such cases because one millionaire may outweigh hundreds of poor people in setting a mean; but he can balance only one mendicant in calculating a median).
The above shows how the numbers are different. Now, time for a bit of back story:
At the age of 41, Mr. Gould was diagnosed with Mesothelioma, a disease which (in 1982) had a median survival time from diagnoses of eight months. Being a scientist, and a statistician, he dug into those numbers to see what they meant for him:
SJG:
The problem may be briefly stated: What does "median mortality of eight months" signify in our vernacular? I suspect that most people, without training in statistics, would read such a statement as "I will probably be dead in eight months" - the very conclusion that must be avoided, since it isn't so...
When I learned about the eight-month median, my first intellectual reaction was: fine, half the people will live longer; now what are my chances of being in that half. I read for a furious and nervous hour and concluded, with relief: damned good. I possessed every one of the characteristics conferring a probability of longer life: I was young; my disease had been recognized in a relatively early stage; I would receive the nation's best medical treatment; I had the world to live for; I knew how to read the data properly and not despair.
I will take a moment and comment here. My plea to you to better understand the use of Median is not meant to be condescending, it is just that we have had this conversation multiple times, and the misreading of the data can, as Mr Gould puts it, lead to despair where there should be hope.
SJG:
...I immediately recognized that the distribution of variation about the eight-month median would almost surely be what statisticians call "right skewed." (In a symmetrical distribution, the profile of variation to the left of the central tendency is a mirror image of variation to the right. In skewed distributions, variation to one side of the central tendency is more stretched out - left skewed if extended to the left, right skewed if stretched out to the right.) The distribution of variation had to be right skewed, I reasoned. After all, the left of the distribution contains an irrevocable lower boundary of zero (since mesothelioma can only be identified at death or before). Thus, there isn't much room for the distribution's lower (or left) half - it must be scrunched up between zero and eight months. But the upper (or right) half can extend out for years and years, even if nobody ultimately survives. The distribution must be right skewed, and I needed to know how long the extended tail ran - for I had already concluded that my favorable profile made me a good candidate for that part of the curve.
Another pause to point out that, as a group, the members of this forum are overwhelmingly right skewed. The median age at diagnoses for CRC is 74 years old, and the very nature of an electronic forum at this point in our history trends our median age much lower (on a guess I would say it is between 50 and 55). That very youth helps us withstand our treatments, keep our blood counts up, and means our bodies are better able to defend themselves from the spread of the cancer (better than someone who is older than 74 anyway). There is also a very strong will to survive among those participating here, much stronger than the general population. So, we, as a group, are strongly right skewed.
The distribution was indeed, strongly right skewed, with a long tail (however small) that extended for several years above the eight month median. I saw no reason why I shouldn't be in that small tail, and I breathed a very long sigh of relief. My technical knowledge had helped. I had read the graph correctly. I had asked the right question and found the answers. I had obtained, in all probability, the most precious of all possible gifts in the circumstances - substantial time. I didn't have to stop and immediately follow Isaiah's injunction to Hezekiah - set thine house in order for thou shalt die, and not live. I would have time to think, to plan, and to fight.
Gould died on May 20, 2002 from a metastatic adenocarcinoma of the lung, a full twenty years after the initial diagnoses, and of a completely unrelated cancer.
Hopefully this helps in your understanding of the numbers, and I hope it also helps you understand why I respond to you when you misinterpret the data so glaringly (up to 3.5 months can be a very scary statement to those on this treatment and dealing with this disease).
The issue of payment by Britain's National Health of course is the subject of this posting, and if I lived in the UK I would take a further interest in the politics, both budgetary and political, involved. However, as Sonia and Pepe point out, we do not fully appreciate that systems complexities and it is not our battle. In the US the use of these drugs to fight CRC is not up for debate, and probably will not be in our lifetimes...
As always John, best of health to you. In many ways we disagree, but your story is inspirational to me and I mean you no insult (even when you end your bits implying that I have no common sense, or that I have not done my research, or that I have some monolithic view supporting chemotherapy in all its uses, all of which are wrong, and all of which could be considered condescending). Thank you also for those messages where we have discussed areas of common concern and where you aided both my spirit and my health.
Blake
Blake,
You're averring that there is a long, fat tail of survivors in CRYSTAL (the study with 20 vs 23.5 months median). Ok, in real life there may be *some* long tail survivors, but how many more than say 5-8% are still alive at 5 years ("old" stage IV survival expectations)? Any real quantitative data plots, even at 3-4 years?
I'm running into hand waving and the normal marketing based, data dredged stats with "relative improvement" scam - I see no quantitative data presented to really show this long fat tail of survival with erbitux. In CECOG - squinting - the last 25 months (out of 31 months data) with FOLFIRI ("best"???) might be approaching radioactive decay with a 12-13 month half life. Does it continue first order kinetics (radioactive decay curve), go sideways (long, fat tail) or nosedive (as is common)?
In Imclone's 2011 retrospective CRYSTAL update, some minor progress based on (sub)population mining is blared in the news, fine. press release. I haven't found the basic Kaplan Meier plots of overall survival that I expect to see trumpeted with a strong success even if it's retrospectively data mined.
I strongly distrust any pharma study or statement that doesn't show the latest Kaplan Meier overall survivals (e.g. the CRYSTAL update, 2011), but maybe I need a subscription somewhere. Can you help us with those plots, Blake?0 -
Hi Tanstaafltanstaafl said:saying vs showing
Blake,
You're averring that there is a long, fat tail of survivors in CRYSTAL (the study with 20 vs 23.5 months median). Ok, in real life there may be *some* long tail survivors, but how many more than say 5-8% are still alive at 5 years ("old" stage IV survival expectations)? Any real quantitative data plots, even at 3-4 years?
I'm running into hand waving and the normal marketing based, data dredged stats with "relative improvement" scam - I see no quantitative data presented to really show this long fat tail of survival with erbitux. In CECOG - squinting - the last 25 months (out of 31 months data) with FOLFIRI ("best"???) might be approaching radioactive decay with a 12-13 month half life. Does it continue first order kinetics (radioactive decay curve), go sideways (long, fat tail) or nosedive (as is common)?
In Imclone's 2011 retrospective CRYSTAL update, some minor progress based on (sub)population mining is blared in the news, fine. press release. I haven't found the basic Kaplan Meier plots of overall survival that I expect to see trumpeted with a strong success even if it's retrospectively data mined.
I strongly distrust any pharma study or statement that doesn't show the latest Kaplan Meier overall survivals (e.g. the CRYSTAL update, 2011), but maybe I need a subscription somewhere. Can you help us with those plots, Blake?You're averring that there is a long, fat tail of survivors in CRYSTAL (the study with 20 vs 23.5 months median).
While I am aware of Crystal, like you I have no access to the full trial results. To answer your question though, I was not implying any such thing, only making the point that Median is not Mean, and that for any trial, the population made up of active members of this forum is more likely to be in the right tail due to youth, will, and other factors.
I do have some links that show survival changes in the last 10 years or so (about a 100% increase), and I will share those via PM. I also appreciate it if we take the discussion there, as some have expressed a sensitivity to the data.
Yours,
Blake0 -
A median questionBuckwirth said:I would like to add...
Betsy,
I hope you don't mind if I add some comments here, you make some good points that I would like to expand on:
1) Most stats come from clinical trials - e.g. Avastin adds 2.5 months to life. Once a drug is approved, there mostly aren't any more significant trials.
Actually, the trial size increases. All of our treatments and the course of our disease is followed by both the CDC and the NIH, and outcomes are reviewed by a variety of sources, including the host of our site, ACS.
2) A significant percentage of patients participating in trials are already out of other options. Most patients who are doing well are not in trials. So, the improved survival stats for Avastin or any similar drug are going to sound pretty small.
This is an excellent point, and goes to my earlier comment on median vs average. Median is literally the patient in the center, not the mathematical average. So, while the median survival increase might be 3.5 months (an 18% increase, btw) the overall survival rate could be much higher. Avastin, Erbitux and surgery for those with metastasis to a single organ, have lead to a doubling of the five year survival stats among Stage IV patients in the last decade.
3) Suppose there was a drug that takes a while to work. Trial patients are typically booted out of the trial if their disease progresses. So, if a drug takes "time" to work, but then works well in some patients, the trial won't have data about those patients. Avastin or Erbitux etc might be drugs like that. Not sure, but it is something to think about.
I'm not sure that is exactly how it works (it would seriously twist the number if it did).
Erbitux failed the initial trial, not working at all in a significant number of trial participants, but a review of the data identified the importance of the KRAS mutation (or lack of it) in the efficacy of the drug. It was that review that allowed Erbitux to pass the FDA approval process.
OK, I have been reading all of this discussion and have a question, although I am ashamed to ask it since I loved math so much as a kid. I am trying to get my head around the definition of median so here is an example, if I understand it correctly. In a study of five people taking a drug, their survival times using the drug are 1, 2, 3, 30 and 40 months. Am I correct in saying that the median survival is 3 months? I anxiously await the answer!0 -
yeslaurettas said:A median question
OK, I have been reading all of this discussion and have a question, although I am ashamed to ask it since I loved math so much as a kid. I am trying to get my head around the definition of median so here is an example, if I understand it correctly. In a study of five people taking a drug, their survival times using the drug are 1, 2, 3, 30 and 40 months. Am I correct in saying that the median survival is 3 months? I anxiously await the answer!
yes0 -
Quick replytanstaafl said:yes
yes
That was fast. Thanks! So, the reality is that if you take into account the fact that a number of people who take these drugs might be very debilitated or elderly, adding quantities of short survival times, the actual results for those who are fairly healthy and younger, could be significantly better. Is that true?0 -
Exactly that!laurettas said:A median question
OK, I have been reading all of this discussion and have a question, although I am ashamed to ask it since I loved math so much as a kid. I am trying to get my head around the definition of median so here is an example, if I understand it correctly. In a study of five people taking a drug, their survival times using the drug are 1, 2, 3, 30 and 40 months. Am I correct in saying that the median survival is 3 months? I anxiously await the answer!
And as your example shows, it is more accurate as an average when dealing with large numbers.0 -
Yeslaurettas said:Quick reply
That was fast. Thanks! So, the reality is that if you take into account the fact that a number of people who take these drugs might be very debilitated or elderly, adding quantities of short survival times, the actual results for those who are fairly healthy and younger, could be significantly better. Is that true?
And that was the point of my posts.
Thanks,
Blake0 -
wow
Wow I didn't realise how bad some countries are in regards to health care!!! I live in Australia and here every single treatment for colon cancer is free for as long as the oncologist recommends it..... I think I will be on Avastin for life as long as it works!!!!!!No cost to me!!!!0 -
Well!Buckwirth said:Yes
And that was the point of my posts.
Thanks,
Blake
So, fine, Blake, what are you trying to say, that I'm a little DENSE? Well, maybe I am but if you had used a SIMPLE example like I just did, I wouldn't have had to read through all of your long-winded explanations until my head SPUN and I couldn't think straight! And I may not be too bright but I am certainly smarter than the DUMMY that came up with the idea of using median survival rates! Aren't caps great? I think I'm going to use them more often.
Anyhow, thanks for repeating yourself until I finally had to think hard enough to get the point!0 -
Thankslaurettas said:Well!
So, fine, Blake, what are you trying to say, that I'm a little DENSE? Well, maybe I am but if you had used a SIMPLE example like I just did, I wouldn't have had to read through all of your long-winded explanations until my head SPUN and I couldn't think straight! And I may not be too bright but I am certainly smarter than the DUMMY that came up with the idea of using median survival rates! Aren't caps great? I think I'm going to use them more often.
Anyhow, thanks for repeating yourself until I finally had to think hard enough to get the point!
for the laugh!
The whole thing is complicated (why most people don't like statistics). Even many of our doctors don't really understand the concept, and they had to pass the advanced class.
I've actually used your example in other posts, but for this one I felt Gould's story would be a good example.
Blake0
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