Sex-related differences in oncological surgery and postoperative outcomes: comprehensive, nationwide study in France.

Background: The main objective of this study was to undertake an exhaustive investigation of sex-related differences in cancer surgery.

Methods: This observational study used data from the French national health insurance system database covering 98.8% of the population. Patients diagnosed with non-sex-specific solid invasive cancers between January 2018 and December 2019 were included. The main outcomes were likelihood of undergoing cancer surgery, type of oncological surgery performed, and associated 30-, 60-, and 90-day postoperative reoperation and mortality rates, by sex.

Results: For the 367 887 patients included, women were 44% more likely than men to undergo cancer surgery (OR 1.44, 95% c.i. 1.31 to 1.59; P < 0.001). However, the likelihood of surgery decreased with advancing age (OR 0.98, 0.98 to 0.98; P < 0.001), and with increasing number of co-morbid conditions (OR 0.95, 0.95 to 0.96; P < 0.001), especially in women. Men had higher 90-day reoperation (21.2 versus 18.8%; P < 0.001) and mortality (1.2 versus 0.9%; P < 0.001) rates than women, overall, and for most cancer types, with the exception of bladder cancer, for which the 90-day mortality rate was higher among women (1.8 versus 1.4%; P < 0.001). After adjustment for age, number of co-morbid conditions, and surgical procedure, 90-day mortality remained higher in men (OR 1.16, 1.07 to 1.26; P < 0.001), and men were 21% more likely than women to undergo reoperation within 90 days (OR 1.21, 1.18 to 1.23; P < 0.001).

Conclusion: Women were much more likely than men to undergo cancer surgery than men, but the likelihood of surgery decreased with advancing age and with increasing number of co-morbid conditions, especially in women. These findings highlight a need for both increased awareness and strategies to ensure gender equality in access to oncological surgical treatment and improved outcomes.