Lung cancer is the deadliest form — and the second most common form — of cancer for both men and women. It affects more women than breast cancer, ovarian cancer, and uterine cancer combined.

Men and women share the same risk factors for contracting lung cancer. This is especially true of chronic exposure to tobacco smoke, which is responsible for 85 to 90 percent of lung cancer diagnoses across the board. The symptoms of lung cancer in women are also virtually the same as those in men.

However, despite these similarities, there are some major differences that can affect the prognosis and treatment of this deadly disease.

While men and women are equally susceptible to lung cancer, they’re not equally susceptible to the same types.

There are two main types of lung cancer:

Small cell lung cancer is generally the most aggressive and rapidly progressing type.

There are three different types of non-small cell lung cancer:

When women contract lung cancer, they’re more likely to present with adenocarcinoma than men are. On the other hand, men are more likely than women to present with squamous cell lung cancer, the most common type in smokers.

One major difference between these lung cancers is that squamous cell produces more symptoms and is easier to detect, thus providing the greatest opportunity for an early diagnosis. An early diagnosis is one of the greatest predictors of survival.

Smoking is the biggest risk factor in developing lung cancer. This risk factor affects men and women differently. There’s no medical consensus on why women smokers are more likely than men smokers to:

  • develop small cell lung cancer
  • suffer DNA damage
  • have less capacity to repair smoking damage

And, there’s no medical consensus on why women nonsmokers are more likely than men to:

  • develop adenocarcinoma
  • receive a diagnosis at an earlier age
  • be diagnosed with localized disease

There’s been a gradual rise in lung cancer mortality among women as opposed to a gradual leveling off among men.

Depending on the specifics of the diagnosis, the treatment for lung cancer for both women and men is usually surgery, radiotherapy, or chemotherapy. The survival rates following treatment are different for women and men with lung cancer. One study found that:

  • The median survival at 1 and 2 years was significantly higher in women.
  • The risk for death was 14 percent lower in women.
  • Women respond better to chemotherapy than men.

This is positive news for women, but women also suffer from problems that men don’t, including:

  • a higher likelihood of developing small cell lung cancer
  • being three times more likely to carry a genetic mutation that aggravates tumors

What accounts for these differences?

There’s no agreement in the medical community for a direct explanation for these differences between men and women. Potential reasons include:

  • hormonal factors, such as estrogen exposure
  • age of onset for smoking since women tend to smoke later in life
  • women are more likely to seek early treatment
  • genetic and lifestyle factors

While lung cancer is less common in women than it is in men, that gap is getting smaller. Women may be more negatively affected by the dangers of smoking. Also, certain hormonal factors can aggravate and spur cancer growth.

Though lung cancer incidence overall is decreasing over time, the incidence of the adenocarcinoma subtype is increasing. With more time, research, and advancements in medicine, a better understanding of the gender gap of lung cancer should eventually be discovered.