When chemotherapy first appeared on the scene as a major treatment for cancer, there were many studies in animals that showed that higher doses of drug were more effective. Higher doses led to more cures – at least in rats! But, unfortunately humans aren’t as tolerant as these little uncomplaining animals and if a few extra rats died because of the high doses, no one mourned.
But women with breast cancer can be tough and many willingly accept high doses of chemotherapy if it promises them a longer life span or even a cure. They often want to see their kids graduate, get married, have children. No surprise then, that thousands would accept treatment with high doses of chemotherapy.
This treatment is called high dose chemotherapy with autologous stem cell support. In the 1980s and 1990s, it became a popular treatment for certain women with breast cancer. These women either had many lymph nodes involved with cancer when the cancer was first discovered or had cancer that had already begun to spread throughout the body. Many major cancer centers hailed this as the next revolution in breast cancer treatment and perhaps a boon to their bottom line as this is a very expensive procedure.
The plan is fairly simple. High doses of chemotherapy will completely devastate the bone marrow, leading to major problems with infection and bleeding, which can often be fatal. So a portion of the women’s bone marrow is taken out and stored. Then after they received their high doses of chemotherapy the bone marrow cells are returned thus preventing major problems with either infection or bleeding.
But insurance companies balked at paying for this. Patients even went to court to fight the insurance companies and inevitably won. What judge or jury would not give a desperate woman a chance to live? But there were enough doubters in spite of the glowing reports of success that clinical trials began to be performed with half the patients receiving standard therapy and the other half receiving the high doses. Some of these studies were actually sponsored by the insurance companies who saw this treatment as a threat to their bottom line. And wanted to be sure it was really as effective as its proponents claimed.
Unfortunately for all the hopeful women (and fortunately for the insurance companies), the high dose treatment proved a bust. Almost all the studies showed no benefit. Yes many times the cancer would regress more fully with the high dose therapy or not come back as quickly, but at the end of the day, women receiving this treatment did not live any longer. And some would die as a result of the treatment either because of infections before the returned bone marrow cells could take hold, or of leukemia because of damage to their bone marrow cells.
All this was brought home to me when two articles appeared in the August 20 issue of the Journal of Clinical Oncology. In these articles research summarized the results of all the clinical trials performed with high doses chemotherapy in women with widespread breast cancer or with early breast cancer that had spread to many lymph nodes. Both papers confirmed that the treatment did not prolong women’s lives. There might have been a very tiny benefit for some, but the toxicity of the treatment made this a bad tradeoff.
All this points to the lesson that we all know. Before beginning a treatment ask the doctor if there is proof that it really works. So much of medical practice, especially oncology, is based on hope rather than reality. It pays to know the facts, especially when the treatment will be as dangerous and toxic as high dose chemotherapy.
Subscribe to:
Post Comments (Atom)
1 comments:
In the 90's, we were subjected to bigger guns, more firepower with high dose chemotherapy and autologous stem cell transplantation, costing as much as $250,000. This tragedy was a watershed event for many advocates, when in 2007, The University of Texas M.D. Anderson Cancer Center had shown this not to be beneficial as an adjuvant therapy.
In a review of 6,200 patients in 15 randomized high-dose chemotherapy studies conducted around the world between 1988 and 2002, Anderson investigators, in collaboration with the European Blood and Marrow Transplant Group, reported that while there was a slight benefit on relapse-free survival, there was no benefit to overall survival.
And what was even more daming, the therapy's stature became even more confusing when data from a large randomized positive trial, presented on the plenary session of the 1999 ASCO meeting, was later found to be falsified.
Donald Berry, Ph.D., professor and head of the Division of Quantitative Sciences at Anderson, presented the findings at the 30th annual San Antonio Breast Cancer Symposium. According to Berry, "What we are learning is that the doses used in standard chemotherapy regimens for advanced breast cancer have reached a plateu and that increasing beyond that dose is not delivering a greater benefit."
You may want to reserve aggressive therapy for those patients who will derive more benefit than harm, while identifying the most promising treatment regimens for everyone. In patients with tumors very resistant to cytotoxic chemotherapy, the most promising treatments may be angiogenesis inhibitors, growth factor inhibitors, or more integrative medicine approaches.
More is not always better.
Post a Comment