It is well-known that cigarette smoking and a history of tobacco use increase the danger of lung cancer. But it isn't the one risk factor, says Dr. Julia Rotow, a thoracic oncologist on the Dana-Farber Cancer Institute in Boston, MA.
“Lung cancer can also affect people you wouldn't expect. For example, younger patients who have no history of smoking. And this is where the data on EGFR mutations become really crucial,” says Rotow.
Rotow refers to epidermal growth factor receptor or EGFR mutated lung cancer. It is a form of cancer that primarily affects young people, especially women, who are inclined to smoke little or under no circumstances. Studies also show that this sort of lung cancer can be particularly common within the East Asian population.
“[The] The rate can be as high as 50 to 60%, so it's an important subset of lung cancer that needs to be identified at diagnosis,” Rotow said throughout the 2023 Annual Meeting of the American Society of Clinical Oncology (ASCO).
EGFR is a form of protein present in your normal cells that helps them grow. However, if you may have an EGFR mutation – an error within the composition of your DNA – it may well cause cells to multiply much faster. This can result in cancerous tumors.
“In lung cancer cells that [EGFR] “can be made unusually active by a mutation, causing it to turn on when it shouldn't,” says Rotow.
There are many varieties of EGFR mutations. Depending on what information is missing or added to your DNA sequence, it may well affect the form of cancer you develop. If you may have an EGFR mutation that causes cells to turn out to be cancerous, grow, and spread throughout your body, experts call it a “driver mutation.”
Rotow said EGFR is probably the most common form of driver mutation, and young people or non-smokers who're diagnosed with lung cancer have a “pretty high” probability of getting this mutation.
Knowing the precise reason behind a mutation-related cancer may also help your doctor prescribe effective, targeted therapy.
“More than 50% – even perhaps greater than 75% – could have a [EGFR driver mutation]. And in lots of cases these will be treated with targeted therapy pills,” says Rotow. “It occurs most ceaselessly in young people, young women and other people of Asian descent.”
Studies show that more than half of Asian American women diagnosed with lung cancer have never smoked before. Among them, women of Chinese descent have a much higher risk. Up to 8 in 10 women diagnosed with lung cancer have never smoked before.
And compared to other ethnic groups, Asian American women who have never smoked are almost twice as likely to develop lung cancer.
“In this population, it is the leading cause of cancer death,” says Rotow.
So what is the link?
As part of a lung cancer screening study presented by Dr. Elaine Shum of New York University at the 2023 ASCO Annual Meeting, more than 200 Asian women under 40 who smoked little or not at all underwent three annual CT chest scans, an imaging test that allows doctors to examine your lungs more closely.
Shum found that nearly 2% of young, nonsmoking Asian women had lung cancer.
“All of the lung cancers they identified were EGFR-mutated tumors that were amenable to adjuvant EGFR-targeted therapy,” says Rotow.
Adjuvant targeted therapy is a type of additional or follow-up treatment that is given after your main treatment plan has been completed, such as surgery or chemotherapy. These therapies target and destroy any cancer cells that may still be present after your main treatment, reducing the chance that your cancer will come back.
Accordingly Current lung screening guidelines from the U.S. Preventive Services Task Force recommend annual testing and scanning for people ages 50 to 80 who smoke 20 packs of cigarettes annually.
“That means either one pack of cigarettes a day for 20 years, two packs a day for 10 years, and so forth,” Rotow says. Additionally, they must currently smoke or have quit within the last 15 years to qualify.
Screening for lung cancer is also important.
Regular lung screenings allow doctors to detect lung cancer early, which not only makes it more treatable but “also improves survival rates,” Rotow said. But the guidelines have limitations and “don't all the time catch everyone who could also be at high risk.”
“For example, “We know that under current guidelines, there are racial and ethnic disparities in both access to lung cancer screening and eligibility for screening,” Rotow says.
In addition, participation in lung cancer screening is usually low: only about three out of ten people join for it.
This, says Rotow, is a “real missed opportunity “to find early-stage lung cancer, which is becoming easier to treat with advanced options that can improve your overall outcome. This includes EGFR-mutated lung cancer, which has been found in high-risk nonsmoking Asian women.
“This highlights the importance of considering not only about our traditional high-risk patient population, who should definitely receive one hundred pc screening at any time when possible, but additionally concerning the other, less common patient populations who can still profit from potential screening strategies,” Rotow says.