Biological sex differences may explain why the risk of most types of cancer is higher for men than women, according to a new study in an American medical journal.

The results of the study, published by Wiley online in the American Cancer Society’s CANCER journal, highlighted that understanding the reasons for sex differences in cancer risk could help improve prevention and treatment of the disease.

Led by Sarah S Jackson of the National Cancer Institute, part of the National Institutes of Health, the study assessed differences in cancer risk for 21 cancer sites among 171,274 male and 122,826 female adults aged 50 to 71 years between 1995 and 2011.

During that time, 17,951 new cancers arose in men and 8,742 in women. The risk for men was lower only for thyroid and gallbladder cancers, while the risks for other types of cancer were between 1.3 and 10.8 times higher in men than women.

The greatest increased risks in men were seen for oesophageal cancer, larynx, gastric cardia and bladder cancer.

Even taking behavioural and environmental difference-  such as smoking, alcohol use and diet - into account, biological differences appeared to be the most significant factor in the number of cancer cases. Biological differences include physiological, immunological, genetic, and other variations.

Dr Jackson said: 'Our results show that there are differences in cancer incidence that are not explained by environmental exposures alone. This suggests that there are intrinsic biological differences between men and women that affect susceptibility to cancer.'

This comes after community pharmacies in England have been asked to spot early signs of cancer and be able to refer patients directly for scans as part of an NHS pilot.