Differences in cancer survival by sex: a population-based study using cancer registry data

Few large-scale studies have investigated sex differences in cancer survival and little is known about their temporal and age-related patterns.

We used cancer registry data for first primary cancers diagnosed between 1982 and 2015 in Victoria, Australia. Cases were followed until the end of 2015 through linkage to death registries. Differences in survival were assessed for 25 cancers using the Pohar-Perme estimator of net survival and the excess mortality rate ratio (EMRR) adjusting for age and year of diagnosis.

Five-year net survival for all cancers combined was lower for men (47.1%; 95% CI 46.9-47.4) than women (52.0%; 95% CI 51.7-52.3); EMRR 1.13 (95% CI 1.12-1.14; p < 0.001). A survival disadvantage for men was observed for 11 cancers: head and neck, esophagus, colorectum, pancreas, lung, bone, melanoma, mesothelioma, kidney, thyroid, and non-Hodgkin lymphoma. In contrast, women had lower survival from cancers of the bladder, renal pelvis, and ureter. For the majority of cancers with survival differences, the EMRR decreased with increasing age at diagnosis; for colorectal, esophageal, and kidney cancer, the EMRR increased with time since diagnosis.

Identifying the underlying reasons behind sex differences in cancer survival is necessary to address inequalities, which may improve outcomes for men and women.