Gender and survival in malignant tumours

Epidemiological evidence supports the existence of a survival advantage for female patients with melanoma. This survival advantage often persists when other prognostic variables are taken into account. The basis for this female advantage or male disadvantage is not established although female sex steroids can retard melanoma invasion in vitro.

In considering the mechanisms involved, we have examined the literature to establish whether this female survival advantage is shared by other solid tumours. The tumours selected were breast, lung, colorectal, oesophageal, gastric, pancreatic and soft tissue sarcoma. A Medline database search was carried out to identify those studies in which gender was investigated as a prognostic indicator.

Results from large, mostly retrospective series show that for 5 of these 7 tumour groups, there is evidence for a female survival advantage. In particular, this survival advantage is usually more prominent in early stage disease.

Melanoma is not unique in showing a female survival advantage. Although the current literature does not address the mechanisms involved, we suggest that these are worth investigating as they may contribute to new treatment modalities aimed at preventing metastatic spread.