High-Dose Chemotherapy As Adjuvant Therapy in Breast Cancer: Could There Be a Survival Benefit?

Abstract

TO THE EDITOR: Results of the recent meta-analysis by Berry et al provide evidence that high-dose chemotherapy (HDC) with hematopoietic stem-cell support prolongs relapse-free survival but does not improve overall survival in patients with high-risk primary breast cancer. In my opinion, a clinical point that needs to be stressed further is the striking 6% rate of death resulting from toxicity in the HDC group (procedure related, in most cases). The high mortality rate is attributable, at least in part, to the use of bone marrow as a source of stem cells in some patients and the highly toxic high-dose regimens (ie, carmustine containing) used in early studies. When patients whose deaths were attributed to toxicity were excluded, an HDC advantage in terms of overall survival was also observed. These data are clinically relevant, because HDC with peripheral-blood stem-cell support is today a safe procedure with a mortality rate and quality-adjusted survival parameters similar to those of conventional therapies. Furthermore, as pointed out by Berry et al, the control arms of some studies (eg, those by the Scandinavian Breast Group and Southwest Oncology Group) have involved nonconventional treatment with increased dose intensity. It would be interesting to know the survival data of only those studies—the vast majority—in which real, conventional control arms have been used. Mauro Moroni San Carlo Borromeo Hospital, Milan, Italy