High-dose chemotherapy followed by autologous hematopoietic stem-cell transplantation for the treatment of solid tumors in adults: a critical review.

High-dose chemotherapy (HDCT) plus autologous hematopoietic stem-cell transplantation (HSCT) has been explored in several solid tumors in the attempt to prevent and/or overcome tumor-cell chemo-resistance, based on in vitro evidence of a "dose-response" effect. Preliminary encouraging results from non-randomized trials, led to an increased use of this strategy in the 1990s. Since the end of the nineties, the fraudulent nature of initial reports in breast cancer, the failure of positive prospective randomized trials, HDCT-related toxicities, determined a dramatic decline of interest in this approach. Loss of accrual in ongoing randomized studies was the first consequence, causing the current unavailability of optimal information. From the review of available published data, the use of HDCT with autologous HSCT may improve tumor response rates and/or possibly progression-free survival, especially in some selected patient subgroups. However, this strategy did not demonstrate in almost all cases to produce significantly higher cure rates than standard-dose chemotherapy. Well-designed randomized studies and future strategies integrating HDCT with concomitant and/or subsequent anti-tumor therapies targeted against the residual disease might be suggested in clinically and biologically selected patients.