Lung cancer is in a class by itself. It's the biggest and baddest cancer out there -- accounting for more diagnoses and deaths than breast, prostate and colon cancer combined.
But for women, lung cancer represents a unique health threat.
Lung cancer diagnoses in women have jumped six-fold over the past three decades, while in men the incidence has gone down.
Women tend to develop lung cancer at younger ages. And women are much more likely to get lung cancer despite never having smoked -- a group that numbers about 25,000 a year. Female lung cancer patients who have never smoked outnumber men never-smokers by 3 to 1.
On the redeeming side, there's this: Women with lung cancer survive longer, regardless of their stage of cancer at diagnosis, the type of lung cancer, or how it's treated.
A new report rounds up quite a few didn't-know-that facts about women and lung cancer. Called Out of the Shadows, it comes from Brigham and Women's Hospital in Boston, with input from the Lung Cancer Alliance, an advocacy group.
The report makes clear that there's a lot cancer scientists don't know about the sex differences in lung cancer. But what they've found out lately underscores the general point that lung cancer needs to be thought of as a collection of malignancies that arise in the lungs.
This is important, because progress in diagnosing and treating this fearsome cancer won't progress until its molecular basis is better understood.
For instance, the report says, women smoke less than men, but seem to suffer more smoking-related DNA damage. Is that because they be less able to clear carcinogens from their lungs, or repair DNA damage?
Similarly, women are more likely to have higher levels or more frequent mutations in biomarkers known to be involved in lung cancer, such as gastrin-releasing peptide factor or epidermal growth factor receptor, or EGFR.
Mutations in EGFR are more common in women who've never smoked, and in those with a type of lung cancer called adenocarcinoma. It was once rare, but now it's the most common kind of lung cancer in men and women of all ages.
There are also important differences in lung cancer incidence among women depending on their ethnic background. There's much more disparity between the sexes among African-Americans, Japanese-Americans and Hawaiians than among U.S. Caucasians.
African-American women have almost the same amount of lung cancer as white women -- despite the fact that African-American women have lower smoking rates.
There's no shortage of urgent questions, but there is a shortage of money to answer them, the report notes. All federal spending for lung cancer research amounts to $1,249 for each lung cancer death. Spending for breast cancer research is 21 times higher -- $27,480 per death.