Wiley: Study shows inherent biological differences between men and women that influence susceptibility to cancer

Why do men face higher rates of most types of cancer than women? New research suggests biological sex differences may be the answer. Most types of cancer occur more often in men than in women, but the reasons for this are unclear. The results of a recent Wiley study published online in Cancer, a peer-reviewed journal of the American Cancer Society, suggest that the reason may be underlying biological sex differences rather than behavioral differences related to smoking, diet, alcohol consumption and other factors.

Understanding the causes of sex differences in risk could provide important information for improving cancer prevention and treatment. To investigate, Sarah S. Jackson, PhD, of the National Cancer Institute, part of the National Institutes of Health, and her colleagues assessed differences in cancer risk across 21 anatomical cancer sites in 171,274 men and 122,826 women adults aged 50-71 who participated in the NIH-AARP Diet and Health Study from 1995 to 2011.

"Our results show that differences in cancer incidence cannot be explained by environmental exposures alone. This suggests that there are inherent biological differences between men and women that influence cancer susceptibility." - Sarah S. Jackson, PhD

During this time, 17,951 new cancers arose in men and 8,742 in women. Only thyroid and gallbladder cancers were less common in men than in women. At other anatomical sites, the risk was 1.3 to 10.8 times higher in men than in women. The greatest increase in risk in men was for cancers of the esophagus (10.8 times increased risk), larynx (3.5 times increased risk), gastric cardia (3.5 times increased risk), and bladder (3.3 times increased risk).

Even after adjusting for a wide range of risk behaviors and carcinogen exposures, the increased risk for most cancers remained in men. In fact, differences in risk behaviors and carcinogen exposures between men and women account for only a small portion of the male advantage for most cancers (ranging from 11% for esophageal cancer to 50% for lung cancer).

The results suggest that biological differences between the sexes – such as physiological, immune, genetic and other differences – play an important role in cancer susceptibility in men and women.

"Our results show that differences in cancer incidence cannot be explained by environmental exposures alone. This suggests that there are inherent biological differences between men and women that influence susceptibility to cancer.

An accompanying editorial discusses the study's findings and notes the need for a multifaceted approach to address sex differences in cancer.

"Sex should be strategically implemented as a biological variable throughout the cancer continuum, from risk prediction and primary cancer prevention, cancer screening and secondary prevention, to cancer treatment and patient management," the authors wrote. "Studying and addressing sex differences in cancer and other diseases is an ongoing quest. Bench-to-bedside translational research that effectively translates existing research findings into clinical practice is a scalable means to achieve precision medicine and will mitigate – and ultimately potentially eliminate – sex differences in cancer."

From cnBeta.COM