Lung cancer prognosis in Spain: the role of histology, age and sex

Survival in the case of lung cancer patients not only remains poor and decreases with advancing age at diagnosis, but recent European studies also report that it differs by sex. Our study sought to describe sex-related differences in lung cancer survival in Spain, and evaluate the role played by histologic type. Our analysis covered seven Spanish regions with population-based cancer registries. Cases diagnosed with lung cancer during the period 1995-1999 were followed up until December 31, 2004. To ascertain possible sex differences we performed multiple regression analysis. Age-standardized 5-year relative survival proved significantly higher in women (11.8%) than in men (9.2%), and among the youngest patients relative survival at 5 years conditional on surviving 1 year, was 1.74 times significantly higher in women than in men. The regression analysis showed that men had a higher relative excess risk of dying (RER) than did women (1.1 [95% CI 1.03-1.18]), with this being particularly marked among the 15-54 age group (1.42 [1.24-1.64]). Analysis by histologic type showed that in small cell carcinoma, men had a higher RER than women (1.29 [1.02-1.61]); in squamous cell carcinoma, men had a significantly lower RER than women during the first and fifth years; and in large cell carcinoma and adenocarcinoma, the RER displayed no significant sex-related differences. Lung cancer survival rates in Spain are poor, with better prognosis in women, especially among patients aged under 55 years at diagnosis, or those with small cell carcinoma.