Evaluation of the effect of age on treatment-related mortality and relapse in patients with high-risk primary breast cancer receiving high-dose chemotherapy

There are contradictory results regarding a potential increased responsiveness of younger women with high-risk primary breast cancer to high-dose compared with standard-dose chemotherapy. Observations from some, but not all, randomized trials, suggest that the potential benefit of high-dose treatment may be limited to younger patients. We analyzed, at median follow-up of 8 years, the prognostic effect of age in 264 patients enrolled in prospective phase II and III trials of high-dose chemotherapy, using a uniform regimen. Median age was 49 (range, 36-71). Among patients ≤ 49 and > 49 years of age, the relapse rates were 27% and 25%, respectively (P = 0.7). In those age groups, the transplant-related mortality rates were 6.5% and 4%, respectively (P = 0.8). No age differences were observed between patients surviving transplant (median age 49) and those who experienced transplant-related mortality (median 47.5) (P = 0.9). Event-free survival (P = 0.3) and overall survival (P = 0.4) did not differ between patients ≤ 49 and > 49 years of age. In conclusion, we did not detect a detrimental effect of older age on transplant-related mortality or relapse after high-dose chemotherapy for high-risk primary breast cancer at long-term follow-up. The debate about the age effect in this population remains unsettled.