Lung cancer is often only linked to smoking or exposure to certain chemicals, without gender or ethnicity being considered. Recent research, however, has found some key differences between men and women when it comes to cancers and to lung cancer in particular. Despite far fewer women smoking cigarettes than men, they still account for nearly half of all new cases. In addition, even though cancer deaths in men have been declining since 1990, lung cancer deaths among women continue to rise. The single greatest risk factor for lung cancer is smoking cigarettes and inhalation of second-hand smoke. This is regardless of gender.
The risk factors for developing lung cancer are similar in both men and women and include: family history, prior medical history of lung cancer or disease, exposure to asbestos, smoke, or radon, poor diet, cigarette smoking, exposure to second-hand smoke. Smoking or exposure to second-hand smoke remains by and large the biggest and most significant risk factor associated with lung cancer. However, among non-smokers, women may be at a higher risk than men. It is believed that there may be genetic and hormonal differences or some combination of the two that may explain these differences in lung cancer development and survival in women.
Researchers have identified several genes of interest that might explain why women are affected differently by lung cancer. Some of these genes are inherited, and some of the others are activated by tobacco exposure. For example:
K-ras is a genetic mutation that, if present, may make cancerous tumors grow quicker and be more likely to spread than when it is not present. Some researchers think that K-ras may make a cancer growth more aggressive when exposed to estrogen, the female sex hormone, as well as other hormones.
Gastric-releasing peptide receptor or GRPR has been associated with cancer cell growth. Like K-ras, this receptor is more active in women and may be driven by exposure to estrogen.
Epidermal growth factor or EGFR is a protein commonly found in lung cancers. Mutations of the gene that produces EGFR are significantly more common in women than in men. Some new medications are able to specifically target abnormalities in this protein, so genetic testing for these mutations is essential to find potential candidates for these drugs.
HER2 is a part of the EGFR family that is found in many cases of adenocarcinomas. It is linked with poorer survival in women with lung cancer.
Talking about the hormonal causes, there are estrogen receptors found on the lung cancer cells of both men and women. Research has shown that in the lab, estrogen encourages the growth of tumor cells and that treatments that block estrogen can help to suppress cancer cell growth. Researchers have also found that a woman’s exposure to estrogen throughout her lifetime may affect her risk for lung cancer. Factors that may affect a woman’s level of exposure includes: number of pregnancies, age at her first period, age at menopause, menstrual cycle details.
Continued research is needed into these crucial differences that occur between women and men who develop lung cancers, as well as into medications that can target the disease. The Althian staff recommendation for you is to live a healthful lifestyle and avoid exposure to smoke, it is the best way for women to reduce their risk of developing lung cancer.