Response to chemotherapy after relapse in patients with or without previous adjuvant chemotherapy for breast cancer. The French Epirubicin Study Group.

The French Epirubicin Study Group undertook a retrospective study to evaluate the response rate at relapse, time to treatment failure, and overall survival according to previous CMF-type adjuvant chemotherapy in patients who had taken part in two successive clinical trials. The statistical significance of the comparisons was tested after adjustment for the factors that differed most between the two groups. Patients who had received previous adjuvant chemotherapy had a lower response rate (p = 0.03), a shorter time to treatment failure (p = 0.007), and shorter overall survival after relapse (p = 0.008); overall survival after initial diagnosis was not significantly different. With respect to patients with axillary node metastases at the time of diagnosis (N+ patients), those with previous adjuvant chemotherapy had a lower response rate (p = 0.01) and shorter time to treatment failure (p = 0.02), but overall survival after relapse and after initial diagnosis were not significantly different. This retrospective and descriptive study suggests that chemotherapy is less effective after relapse, as measured by response rate and time to treatment failure, in patients with previous adjuvant chemotherapy.