Is there a relationship between case volume and survival in breast cancer?

Background Several studies have suggested that case volume predicts survival in breast cancer, that patients treated in hospitals with larger case volumes survive longer. The present study is a review of cases from the Blue Mountain Regional Tumor Registry and tests that hypothesis. Methods A review was made of 2,409 breast cancer cases accessioned from nine hospitals between 1980 and 1995, tabulating hospital annual case volume, stage at diagnosis, age, treatment, and 5-year relative survival rate. Correlations and probabilities are presented. Results Survival correlates with stage at diagnosis (P <0.001), but not with hospital case volume (P = 0.40). Conclusions If, as in this study, survival correlates with stage at diagnosis and not with case volume, then improving survival requires identifying cases earlier. To do that requires improving saturation of the population at risk with effective screening and improving access to healthcare. That implies dispersing services instead of concentrating them in high-volume centers.