Recent research suggests that biological differences largely explain why men are more likely than women to develop certain cancers.
A male “susceptibility” to cancer
It is estimated that approximately one in two men will develop some form of cancer During his life, once morest one in three women. For many years, doctors believed that such a difference was due to the fact that the former were more likely to adopt risky behaviors (smoking, alcohol, etc.) and to practice professions (factory work in particular) involving increased exposure to carcinogens.
Nevertheless, lifestyle choices are not enough to explain this gappersisting once all factors other than sex have been taken into account (pediatric cancer specialists have noted a similar bias in babies and very young children with leukaemia).
Recently, various works have suggested a “ susceptibility ” male to intrinsic cancer, and it turns out that the new study, recently published in the journal CANCER, gives more weight to this hypothesis. Having focused on more than 170,000 men and 122,000 women aged 50 to 71 and followed for more than fifteen years, it assessed the risk for 21 different types of cancer.
During the follow-up period, 17,951 new cancers were diagnosed in male subjects once morest 8,742 in female subjects. Overall, the first cities were 11 times more likely to develop esophageal cancerand presented a 3.5 times higher risk of laryngeal cancer, stomach and bladdereven following adjusting for a wide range of risk behaviors and exposure to known carcinogens.
Intrinsic biological differences
« Our results show that environmental exposures only partially explain gender differences in cancer incidence “, explains Sarah Jackson, lead author of the study. ” They suggest that there are intrinsic biological differences. »
Although this is a purely observational study, not allowing to determine a causal relationship, sex steroid hormones might explain some of these differences. High levels of testosterone have previously been linked to a higher risk of skin and liver cancer in men, and progesterone and estrogen linked to lower rates of colon cancer in women.
« Stronger innate and adaptive immune responses in women may reduce cancer susceptibility “, speculate the authors of the study. ” Women show a more robust immune response to oncogenic infections, such as hepatitis B and C viruses and human papillomavirus, which would induce a lower risk of liver and oropharyngeal cancers respectively.. »
