Does family history influence survival in breast cancer cases?

Abstract

A few studies have suggested a relatively better prognosis for breast cancer (BC) cases reporting a positive family history (FH). We aimed at comparing the survival of patients according to FH in a large hospital-based series of 1,278 BC cases. Information on FH for BC was obtained at diagnosis by interview. All cases reporting a first- or second-degree FH for breast carcinoma were compared with cases without FH. Overall survival was estimated using a product-limit method. Hazard ratios (HRs) and the corresponding 95% confidence intervals (95% CIs), adjusted for confounding factors, were computed using proportional hazard models. Overall, 240 (18.8%) cases reporting, at diagnosis, a positive FH (156 with at least 1 first-degree relative and 84 with at least 1 second-degree relative) were compared with 1,038 patients without FH for BC. No significant differences were found in terms of distribution of age at diagnosis, tumor stage, nodal involvement, receptor status and histology. Cumulative survival rates at 5 years for cases without FH and with first-degree and second-degree FH for BC were 79.8 (95% CI 77.0-83.0), 78.6 (95% CI 70.0-88.0) and 80.2 (95% CI 68.0-92.0), respectively (log-rank test, chi(2) (2) = 0.02, p = 1.0). After adjustment for age, pathologic size and nodal involvement, the HR among cases of invasive cancer with a first-degree FH of BC was 0.91 (95% CI 0.55-1.48); however, the HR for cases with second-degree FH was 1.18 (95% CI 0.62-2.25) compared to cases without FH. Our study, based on a large series of consecutive invasive BC cases, did not find any significant survival differences associated with a positive FH for breast carcinoma, suggesting the existence of a large heterogeneity among BC cases with FH.