A study by a team of researchers at M.D. Anderson Cancer Center in Houston revealed at the San Antonio Breast Cancer Symposium that that high-dose chemotherapy (followed by a stem-cell transplant to rebuild the immune system) after surgery does not extend the life of breast-cancer patients.

The result of a thorough analysis of 15 trials involving 6,200 patients, the new findings supports for closing the chapter of the controversial treatment that was popular during the 1980s and 1990s.

At the time, doctors believed chemotherapy was effective, but it was painful for patients; oncologists thought ramping up chemo would ultimately benefit patients by destroying any cancer cells that had eluded the surgeon's knife.

Donald Berry, Ph.D., of M. D. Anderson Cancer Center in Houston, Texas, the lead author of the study firmly reiterated that high-dose chemotherapy, combined with stem cell supplements, showed little or no overall survival benefit, compared with standard dose chemotherapy, in women with primary breast cancer at high risk of recurrence.

Dr. Berry said, "We have new and better treatments" for breast cancer, he said, so that the arduous high-dose approach is no longer needed.”

Dr. Berry told, the 15 studies showed –

• There was no overall survival benefit. The hazard ratio was 0.94 in favor of the high-dose approach, but the 6% difference was not statistically significant.
• There was an apparent benefit in terms of relapse-free survival. The hazard ratio was 0.87 in favor of the high-dose approach, and the 13% difference was statistically significant at P=0.0005.
• After adjusting as well for hormone receptor status in the subset for which it was available, high-dose chemotherapy significantly prolonged disease-free survival (HR: 0.83, 95% CI: 0.77 to 0.90, P<0.0001).
• Also after those adjustments, high-dose chemotherapy had a modest and marginally significant benefit on breast-cancer specific survival (HR: 0.88, 95% CI: 0.79 to 0.97, P=0.013) and overall survival (HR: 0.89, 95% CI: 0.82 to 0.98, P=0.016).

Dr. Berry told that his team also analyzed the 15 studies in terms of various patient subsets, including age, menopausal status, number of positive nodes, tumor size, histology, and hormone receptor status.
The multistep therapy requires doctors to extract bone-marrow stem cells from breast-cancer patients prior to surgery. After the tumor-removal operation, patients are exposed to brutal doses of chemotherapy, then re-infused with their stem cells, which restore immune cells destroyed by the chemotherapy.

However, the ultrahigh doses of chemo are extremely toxic, and in fact, some of the 20,000 women who have received the treatment in the U.S. have died from the toxicity. The arduous high-dose treatment is associated with serious side effects, including infection, nausea, vomiting, and debility. It also destroyed the patient's bone marrow, which was meant to be rescued by autologous stem cells collected before the start of treatment. The therapy became popular in the 1990s, when some small, nonrandomized studies suggested a benefit for women with 10 or more axillary nodes positive for cancer.