The experts took other opportunities to pound home the point that every treatment plan will be individualized and that doctors need to spend adequate time going over the pluses and minuses of each option with their patients. The panel's strongest suggestion was a call for hormone therapy for all patients with early breast cancer who show any amount of estrogen receptor protein in their tumors. Several panel members expressed concern about strongly recommending a drug whose adverse effects include an increased risk of endometrial cancer and thrombosis. Peto's colleague from the University of Oxford, Christina Davies, MSc, addressed the issue by stating that the benefits of tamoxifen outweigh the risks as measured by lives saved vs lives lost by 30 to one. Multiple drug combinations are superior to single agents and should be given in four to six courses over 3 to 6 months.
Additional courses add significant toxicity without any additional benefit, according to the panel.
But the question of which of the many multidrug regimens is superior remained unanswered. A tepid endorsement went to anthracyclines, a class of drugs that includes doxorubicin and epirubicin, well known for their intense toxicities. The drugs can cause heart problems, they continued, but this appeared to be an issue only for patients with preexisting conditions. The most contentious issue of the conference revolved around taxanes, already successful against advanced breast cancer. The dialogue unexpectedly veered when data from an ongoing study showed no survival improvement for women given paclitaxel in addition to regular chemotherapy.