Lung cancer is the second most common form of cancer next to breast cancer. However, lung cancer is the leading cause of cancer-related death among women in the U.S., surpassing breast cancer in 1987. In fact, over the past 40 years, the lung cancer death rate fell among men by 17%, while increasing by 94% among women.
Although the risk factors for developing lung cancer and lung cancer symptoms are similar between men and women, there are a few considerations women should be mindful of when seeking cancer care.
Lung Cancer Types Affecting Women
There are two main types of lung cancer: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). NSCLC can then be divided into three different subtypes: adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. One’s sex may be correlated with a higher rate of development for different types of lung cancer.
Among people who have never smoked, women are more likely than men to develop certain types of lung cancer. Women are more likely to develop non-small cell lung cancer, especially adenocarcinoma, which is not usually associated with smoking. They also tend to receive these diagnoses at a younger age than men who develop lung cancer.
On the other hand, men are more likely to develop squamous cell carcinoma compared to women, which is associated with smoking. However, since squamous cell carcinoma tends to present symptoms earlier than adenocarcinoma, it can be tested and discovered earlier, presenting a challenge to survival rates for women.
Among men and women who do smoke, women are more likely to develop small cell lung cancer, have DNA damage, and have less capacity to repair smoking damage.
More research is needed to understand the underlying risk factors that lead to these outcomes, but some have conjectured that carcinogens may have a larger impact on women than men, as well as genetic and hormonal differences that can facilitate unchecked cell growth.
Effects of Genetic and Hormonal Differences in Lung Cancer
According to a 2014 review, the effects of certain biomarkers, in combination with the hormonal traits of women, show early evidence of why lung cancer death is the leading cause of cancer death for women.
- KRAS: Mutations to the KRAS gene can make it more likely for tumors to grow and spread. It has been suggested that exposure to estrogen can make KRAS-positive tumors grow more aggressively.
- EFGR: This common mutation to the EGFR protein is more common in women than in men. HER2, a group of genes within the EGFR gene, is seen commonly in adenocarcinoma patients, which is linked to poorer survival rates.
- GRPR: The GRPR receptor is also linked to tumor cell growth and is more active in women. It’s hypothesized that estrogen also increases a mutated receptor’s role in cancer cell growth.
- Estrogen: Further suggesting estrogen’s amplifying effects of the previously mentioned biomarkers, research suggests that when estrogen is blocked, lung cancer growth is suppressed.
Learn more about how important genetic biomarkers and biomarker testing are, and how they affect your treatment.
Lung Cancer Treatments in Women
Although lung cancer remains to be the leading cause of cancer death in women, women actually tend to live longer than men with lung cancer and respond better to chemotherapy and thoracic surgery compared to men. Similarly to the causes of lung cancer, it is hypothesized that women tend to respond differently to different treatments due to hormonal differences (i.e. estrogen exposure), later onset of smoking in women, women being more likely to seek early treatment, and other genetic factors. However, the specific treatment plan should be customized to an individual’s needs, regardless of gender, and discussed thoroughly with one’s cancer care team. Learn more about different types of lung cancer treatments below.