The combined effect of age and socio-economic status on breast cancer survival.

The study aims to investigate the effect of age and socio-economic status (SES) on breast cancer relative survival at 5 years from diagnosis (RS-5%). The Liguria Region Cancer Registry collected clinico-pathological information for 1081 patients resident in Genoa city diagnosed in 1996 and 2000. Patients were divided into three age groups (0-49, 50-69 and ≥70 years) and into quintiles of SES, measured according to a synthetic regional deprivation index built by Census tract variables and validated by comparison with the national deprivation index. The association of prognostic factors and RS-5% was evaluated by bivariate and multivariate analyses. RS-5% was very high for the first two age groups (91%) and decreased in patients aged 70 or older (82%) (unadjusted HR=2.7, P=0.001). The first four SES quintiles had homogeneous RS-5% (89-92%) and only the last very deprived group had lower rates (77%) (unadjusted HR=2.3, P=0.011). Very deprived elderly patients showed a much lower RS-5% (58%). Elderly and very deprived women were more likely to have large tumours, positive lymph nodes and less likely to receive conserving surgery, axillary dissection and adjuvant therapies. After adjusting for tumour characteristics and treatment modalities the increased risk of dying in the elderly disappeared completely, while the higher risk of very deprived women was eliminated only after correction for all the covariates simultaneously. The survival observed for breast cancer patients resident in Genoa was very high, however elderly and very low SES women have to be monitored. These variations are probably due to inequity in healthcare access and to a difficult taken in charge.