Men are more likely to be diagnosed with mesothelioma than women. This is due, in part, to the strong association between mesothelioma and exposure to asbestos in historically male-dominated industries. However, there are some cases of mesothelioma in women. A new study has found that, among those diagnosed with mesothelioma, women tend to live longer than men.
The study, carried out by researchers in Australia, investigated differences in survival between male and female participants with 25 types of cancer.[i] Specifically, the researchers were interested in the proportion of men and women alive 5 years post-diagnosis (‘5-year survival rate’).
According to the American Cancer Society, the 5-year survival rate in those diagnosed with stage 1A mesothelioma is around 16%, and the 5-year survival rate in those diagnosed with stage IV mesothelioma is less than 1%.[ii]
The data for the new study was collected from cancer registries in Victoria, Australia, between 1982 and 2015.
For all 25 cancer types grouped together, the male and female test subjects had a 5-year survival rate of 47.1% and 52.0%, respectively. Male survival rates were lower than female rates in 11 types of cancer, including mesothelioma, whereas female survival rates were lower than male rates in just 3 types of cancer. The finding that women with mesothelioma survive longer than men with mesothelioma was deemed to be statistically significant.
The study authors do not discuss or hypothesise why certain types of cancer have different survival rates. However, identifying why sex affects overall cancer survival, or specific types of cancer survival, may lead to improved outcomes for all patients.
It is important, when considering any study on survival rates, to bear in mind that researchers will often use historic cohort data, which may not include patients treated with the most up-to-date of therapies.
This month, Professor James P Allison and Professor Tasaku Honjo received the Nobel Prize for immune checkpoint therapy, otherwise known as immunotherapy.[iii] We have regularly reported in BC Disease News that immunotherapy drugs, such as Keytruda© and Opdivo©, have yielded success in clinical trial cancer patients. Research is still in its infancy, but remains a particularly promising option.
It will be interesting to see whether future studies demonstrate a change in male and female survival rates after patients have been treated with novel therapies, such as immunotherapy.
[i] Afshar, N. et al. Differences in cancer survival by sex: a population-based study using cancer registry data. Cancer Causes Control (2018). doi:10.1007/s10552-018-1079-z https://www.ncbi.nlm.nih.gov/pubmed/30194549 (Accessed 2 October 2018)
[ii] Survival rates for malignant pleural mesothelioma. American Cancer Society. https://www.cancer.org/cancer/malignant-mesothelioma/detection-diagnosis-staging/survival-statistics.html (Accessed 2 October 2018)