[41] A pooled analysis on the interaction between HER-2 expression and responsiveness of breast cancer to adjuvant chemotherapy.
Gennari A, Sormani MP, Puntoni M, Bruzzi P.. National Cancer Research Institute, Genoa, Italy; University of Genoa, Genoa, Italy
BACKGROUND: A systematic review was undertaken to evaluate the interaction between HER-2 expression and responsiveness of breast cancer to adjuvant chemotherapy. METHODS: Randomised studies of adjuvant chemotherapy, comparing anthracycline-based with non-anthracycline-based regimens, which reported subset analyses according to HER-2 expression, were identified. Recurrence and mortality hazards ratio (HR) were the outcome measures. Pooled estimates, based on published data, of the Disease Free Survival (DFS) HRs and Overall Survival (OS) HRs were obtained, according to standard meta-analysis procedures. RESULTS: Seven eligible studies, providing outcome data according to HER-2 expression, were retrieved. Overall, HER-2-expression data were available in 5099 out of the 6296 patients randomised into the 7 studies (80.9%), with 27.8% HER-2 overexpression rate. The DFS HR pooled estimate (anthra vs non-anthra) was 0.71 (CI 0.61-0.83, p .0001) in HER-2-positive (heterogeneity chi25 = 5.2, p= .39) and 0.98 (CI 0.88-1.09, p .75) in HER-2-negative patients (heterogeneity chi25 = 5.5, p= .36), and the OS HR pooled estimate was 0.73 (CI 0.62-0.85, p .0001) in HER-2-positive (heterogeneity chi25 = 1.7, p= .88) and 1.03 (CI 0.92-1.16, p .59) in HER-2-negative patients (heterogeneity chi25 = 6.2, p= .28) for OS. The test for interaction (treatment x HER-2 expression), both for DFS and OS, yielded highly significant results (DFS chi2 = 10.9, p <.001, OS chi2 = 12.0, p <.001). CONCLUSIONS: The advantage of anthracycline-based over non-anthracycline-based regimens, as adjuvant breast cancer therapy, appears to be more marked, or present only, in the subset of HER-2-positive patients.
| Disease Free Survival | Overall Survival | | HER-2 + | HER-2 - | | HER-2 + | HER-2 - | | Study | HR (95% CI) | HR (95% CI) | Study | HR (95% CI) | HR (95% CI) | | Brussels | 0.70 (0.27-1.83) | 1.19 (0.69-2.05) | GUN 3 | 0.85 (0.27-2.69) | 1.64 (0.85-3.15) | | Milan | 0.83 (0.46-1.49) | 1.22 (0.91-1.64) | Milan | 0.61 (0.32-1.16) | 1.26 (0.89-1.79) | | NSABP B15 | 0.84 (0.65-1.08) | 1.02 (0.86-1.20) | NSABP B15 | 0.82 (0.63-1.06) | 1.07 (0.88-1.30) | | NSABP B11 | 0.60 (0.44-0.82) | 0.96 (0.75-1.23) | NSABP B11 | 0.66 (0.47-0.92) | 0.90 (0.69-1.18) | | DBCCG | 0.75 (0.53-1.06) | 0.79 (0.60-1.05) | DBCCG | 0.73 (0.50-1.05) | 0.82 (0.59-1.13) | | NCIC MA5 | 0.52 (0.34-0.80) | 0.91 (0.71-1.17) | NCIC MA5 | 0.65 (0.42-1.01) | 1.06 (0.80-1.40) | | Pooled estimates | 0.71 (0.61-0.83) p = 0.0001 | 0.98 (0.88-1.09) p = 0.75 | Pooled estimates | 0.73 (0.62-0.85) p = 0.0001 | 1.03 (0.92-1.16) p = 0.59 |
Sunday, December 17, 2006 9:30 AM
General Session 7 (9:00 AM-11:30 AM)
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