Dr. David Gerber on Lung Cancer

Dr. David Gerber answers questions about lung cancer.

Q:

How are medical therapies used in treatment for lung cancer?

A:

Medical therapies, such as chemotherapy and targeted intravenous (IV) and oral therapies, are the mainstay of stage IV lung cancer treatment. At that stage, usually surgery and radiation aren’t offered – it’s just medical therapy. For stage III lung cancer, usually medical therapies aren’t the only treatment. Instead, it’s often a combination of medical therapies with radiation, surgery, or both. We also know that medical therapies may be helpful in certain cases for people with early-stage lung cancer after the cancer is resected surgically. As medical oncologists, we may also be involved in counseling patients who may not need medical therapies but could be helped by our evaluation or opinion.

Q:

How are advances in molecular profiling improving lung cancer treatment?

A:

Molecular profiling refers to evaluation of tissue from a biopsied or removed cancer that goes beyond a routine pathology evaluation. Knowing what’s going on in the DNA or the proteins of a cancer can tell us information about prognosis and treatment. We have advanced our ability to detect and understand subsets of lung cancer based on their molecular profiles. And we’re also advancing our ability to treat these subsets. We look for driver mutations – abnormalities that are the reason the cancer developed and is growing. If you can figure out which are the important ones, then you can give a drug that targets that mutation, and you can have a dramatic effect on a cancer. Currently, we have established treatments directed against about five driver mutations in lung cancer. For example, the most commonly found is a mutation in a molecule known as EGFR, or epidermal growth factor receptor. That’s an abnormality that’s found in about 10 percent of lung cancer cases. It’s most commonly found in people who have lung cancer who have smoked very little, smoked a very long time ago, or didn't smoke at all. If your cancer has a mutant EGFR molecule, you can be treated with an EGFR inhibitor. It’s an oral drug. The chances of the EGFR inhibitor controlling the cancer are about 90 percent. When we give chemo for lung cancer in general, the chance of it controlling the cancer for a period of time is close to 50 percent.

Q:

Is lung cancer screening useful?

A:

Recent data showed that lung cancer screening with CT scans decreased lung cancer mortality. Since then, a number of organizations have endorsed lung cancer screening. Lung cancer is a complicated screening because 95 percent of abnormal scans are false positives. How we guide patients through the potential psychosocial distress of being told they have a positive scan is challenging. Screening needs to be implemented at a place that has a way of navigating patients through this process. At UT Southwestern, we have a screening program in place, and that program is set up to offer the best care. It’s run by a pulmonologist, and it involves a psychologist who not only counsels patients about scan results but also works intensively on smoking cessation with patients who are still actively smoking. That’s a critical component. Lung cancer screening may be useful, but it will take a lot of thought to see how this is implemented in the best way for people.