High-dose chemotherapy with autologous stem-cell support as adjuvant therapy in breast cancer: Overview of 15 randomized trials Journal of Clinical Oncology, 07/21/2011

Berry DA et al. – Adjuvant HDC with AHST prolonged RFS in high-risk primary breast cancer compared with control, but this did not translate into a significant OS benefit. Whether HDC benefits patients in the context of targeted therapies is unknown.

• Assembled individual patient data from 15 randomized trials that compared HDC versus control therapy without stem-cell support
• Prospectively defined primary end points were RFS and OS
• Compared effect of HDC versus control by using log-rank tests and proportional hazards regression, and we adjusted for clinically relevant covariates
• Subset analyses were by age, number of positive lymph nodes, tumor size, histology, hormone receptor (HmR) status, and human epidermal growth factor receptor 2 (HER2) status

• Of 6,210 total patients (n = 3,118, HDC; n = 3,092 control), the median age was 46 years; 69% were premenopausal, 29% were postmenopausal, and 2% were unknown menopausal status; 49.5% were HmR positive; 33.5% were HmR negative, and 17% were unknown HmR status. The median follow-up was 6 years
• After analysis was adjusted for covariates, HDC was found to prolong RFS; HR, 0.87; 95% CI, 0.81 to 0.93; P < .001) but not OS; HR, 0.94; 95% CI, 0.87 to 1.02; P = .13)
• For OS, no covariates had statistically significant interactions with treatment effect, and no subsets evinced significant effect of HDC
• Younger patients had significantly better RFS on HDC than did older patients