Socioeconomic Effects On Breast Cancer Survival : The Role Of Stage And Morphology

Kaffashian, Farrokh (2005). Socioeconomic Effects On Breast Cancer Survival : The Role Of Stage And Morphology. MPhil thesis The Open University.

DOI: https://doi.org/10.21954/ou.ro.0000f64b

Abstract

Background: Breast cancer patients of lower socioeconomic status tend to have poorer survival. This does not seem to be attributed solely to stage at presentation, but there is uncertainty as to the proportion of the survival deficit that is due to stage, and whether this is affected by the method of determining socioeconomic status. In this study, we estimate the extent to which the differences in survival by socioeconomic status, measured both by occupational and area-based methods, can be explained by differences between socioeconomic groups in stage and morphological type of tumour.

Method and materials: We studied survival in 10,865 cases from the East Anglian Cancer Registry diagnosed between 1982 and 1993.

Results: In univariate analyses, lower social class was associated with relative hazards of 1.25 (95% Cl, 1.14-1.38) for death from all causes and 1.32 (95% Cl, 1.12-1.55) for death from breast cancer as underlying cause. Women resident in the most deprived area had relative hazards of 1.29 (95% Cl, 1.16-1.45) for death from all causes and 1.21 (95% Cl, 0.95-1.54) for death from breast cancer as underlying cause. Stage at diagnosis accounted for 28% of the effect of social class on survival to death from breast cancer. For survival to death from any cause, stage accounted for 63% of the effect of social class and 31% of the effect of deprivation category.

Discussion: The major finding is that we could not wholly or even largely account for socioeconomic effects on breast cancer survival by pathological factors including stage and morphology. It is concluded that stage at presentation explains some of the socioeconomic differences in breast cancer survival. Future research on histological grade and socioeconomic status is indicated. It would be useful to confirm these findings in additional studies that include other individual socioeconomic indices in addition to area-based and occupational measures.