Ovarian cancer reoccurence

A chemo-induced gene mutation can happen when the original chemo received does not work. The cancer comes back. When it does this, the cancer comes back more aggressively. The mutagenic effects (changes in form) of chemotherapy on a genetically-unstable tumor, drives the tumor into a state of more aggressive behavior. You might kill off a whole lot of cancer, only to cause a mutation in the remaining cancer, such that the remaining cancer behaves in a more aggressive fashion.

Cancers that are a product of these genetic mutations release cells from the usual controls of proliferation and survival, making them so much harder to fight it. Following this mutation, the cancer cells acquire the ability to proliferate without the normal restraints. As the cancer grows, it may infiltrate and destroy the surrounding tissue, and metastasize by penetrating into blood vessels, lymph nodes, and body cavities. Distant metastasis via the bloodstream may affect virtually any organ (the lungs, bones, liver, adrenals, and the brain).

The FDA has just approved Gemzar (gemcitabine) in combination with Carboplatin for women facing recurrent ovarian cancer. It showed that patients treated with a combination of Gemzar and Carboplatin experienced a significant improvement in survival and response rates. Cell culture assays have verified this.

Clinical Oncologists for Individualized Treatment of cancer patients had found out years ago that the combination of Gemzar (gemcitabine) + platinum (either cisplatin, carboplatin or oxaliplatin) was the most important drug combination introduced for the treatment of solid tumors in the past 18 years. Clinical responses with this regimen were unprecedented.

Individualized testing of the gemcitabine + platinum combination began in the mid-1990s by Dr. Robert Nagourney, Director of Rational Therapeutics, Inc. Many patients received treatment with this regimen because of individualized testing long before any clinical trials in their particular disease types had ever been published.

The contribution of Dr. Nagourney in terms of recognizing the synergistic effects of this combination had been very important in getting clinical trials with this regimen started in a broad spectrum of cancers. Think of all the many cancer patients that were helped by this, long before these clinical trials ever started?

bebo said:

Does it matter which platinum drug? I did six rounds of carbo/taxol initilally. My ca-125 went to normal after 2 treatments. Supposed to be a good sign. I was 6 for the last 3 treatments. Treatment ended in January. In April it was 9 and in May it was 46. I was put on an experimental drug and it wen to 121 after a month on the drug. I have had one round of gemzar/cist, in the second week they gave me just gemzar. The cist made me very sick for 2 days. So, I was going to see about switching to carbo and doing the combo weekly for 2 weeks and then a week off. What do you think of switching?

Thank you so much,

Debbie

Cisplatin can have more toxicity with it than Carboplatin (whether single-agent or in combination). Amifostine may reduce platinum toxicity.

Why do patients with histologically similar tumors respond differently to standard drug treatments? That is one of the main problems associated with chemotherapy. Patient tumors with the same histology do not necessarily respond identically to the same agent or dose schedule of multiple agents.

In patients with cancer, it is often difficult to select an effective treatment because the tumor develops resistance to many drugs. Currently, physicians select an empirically-selected drug and must wait about six months to see whether it is effective on a particular patient. For many cancers, especially after a relapse or when a particular treatment is ineffective, more than one standard treatment exists.

Cancer patients usually undergo four or five courses of chemotherapy before medical oncologists can tell whether the treatment is having an effect. By that time, the tumor may have grown so large that it is too late to switch to another chemotherapy regimen or the patient may be so weakened by the treatment that trying another approach is not immediately feasible. Medical oncologists treat a lot of patients but they don't know going into treatment if it's going to work.

Conventionally, oncologists make chemotherapy treatment recommendations on the basis of published reports of clinical trials in choosing chemotherapy regimens. But the statistical results of these population-based studies might not apply to an individual. For many cancers, more than one standard treatment exists (your treatment should be individualized to your cancer). The system is overloaded with drugs and underloaded with wisdom and expertise for using them. Here is where testing your individual tumor cells would have made a difference, the first time around.