What’s New in Lung Cancer Research?

Research into the prevention, early detection, and treatment of lung cancer is being done in many medical centers worldwide.

Prevention

Tobacco

Prevention offers the greatest opportunity to fight lung cancer. Decades have passed since the link between smoking and lung cancers became clear, but smoking is still responsible for most lung cancer deaths. Research is continuing on:

• Ways to help people quit smoking and stay tobacco-free through counseling, nicotine replacement, and other medicines
• Ways to convince young people to never start smoking
• Inherited differences in genes that may make some people much more likely to get lung cancer if they smoke or are exposed to someone else’s smoke (secondhand smoke)

Environmental causes

Researchers also continue to look into some of the other causes of lung cancer, such as exposure to radon and diesel exhaust. Finding new ways to limit these exposures could possibly save many more lives.

Diet, nutrition, and medicines

Researchers are looking for ways to use vitamins or medicines to prevent lung cancer in people at high risk, but so far none have been shown to clearly reduce risk.

Some studies have suggested that a diet high in fruits and vegetables may offer some protection, but more research is needed to confirm this. While any protective effect of fruits and vegetables on lung cancer risk is likely to be much smaller than the increased risk from smoking, following the American Cancer Society dietary recommendations (such as staying at a healthy weight and eating a diet high in fruits, vegetables, and whole grains) may still be helpful.

Early detection

As mentioned in Can Lung Cancer Be Found Early?, screening with spiral CT scans in people at high risk of lung cancer (due to smoking history) lowers the risk of death from lung cancer, when compared to chest x-rays.

Another approach now being studied uses newer, sensitive tests to look for cancer cells in sputum samples. Researchers have found several changes often seen in the DNA of lung cancer cells. Studies are looking at tests that can spot these DNA changes to see if they can find lung cancers at an earlier stage.

Diagnosis

Fluorescence bronchoscopy

Also known as autofluorescence bronchoscopy, this technique might help doctors find some lung cancers earlier, when they are likely to be easier to treat. For this test, the doctor inserts a bronchoscope through the mouth or nose and into the lungs. The end of the bronchoscope has a special fluorescent light on it, instead of a normal (white) light.

The fluorescent light causes abnormal areas in the airways to show up in a different color than healthy parts of the airway. Some of these areas might not be visible under white light, so the color difference can help doctors find these areas sooner.

Electromagnetic navigation bronchoscopy

Lung tumors near the center of the chest can be biopsied during bronchoscopy, but bronchoscopes have trouble reaching the outer parts of the lungs, so tumors in these areas often need to be biopsied by passing a needle through the skin.

This newer approach can help a doctor use a bronchoscope to biopsy a tumor in the outer part of the lung. First, CT scans are used to create a virtual bronchoscopy. The abnormal area is identified, and a computer helps guide a bronchoscope to the area so that it can be biopsied. The bronchoscope used has some special attachments that allow it to reach further than a regular bronchoscope.

This takes special equipment and training, and it is not widely available at this time.

Treatment

Surgery

Doctors now use video-assisted thoracic surgery (VATS) to treat some small lung tumors. This procedure lets doctors remove parts of the lung through smaller incisions, which can mean shorter hospital stays and less pain for patients. Doctors are now studying if VATS can be used for larger lung tumors.

In a newer approach to this type of operation, the surgeon sits at a specially designed control panel inside the operating room to maneuver long surgical instruments using robotic arms. This approach, known as robotic-assisted surgery, is now being used in some larger cancer centers. It is not clear at this time if this type of surgery is better than current traditional surgery for lung cancer.

Real-time tumor imaging

Researchers are looking to use new imaging techniques, such as four-dimensional computed tomography (4DCT), to help improve treatment. In this technique, the CT machine scans the chest continuously for about 30 seconds. It shows where the tumor is in relation to other structures as a person breathes, as opposed to just giving a ‘snapshot’ of a point in time, like a standard CT does.

To help doctors deliver radiation more precisely to a tumor, 4DCT can be used to determine exactly where the tumor is during each part of the breathing cycle. This technique might also be used to help show if a tumor is attached to or invading important structures in the chest, which could help doctors determine if a patient might be eligible for surgery.

Targeted therapy drugs

Researchers are learning more about the inner workings of lung cancer cells that control their growth and spread. This work had led to the development of new targeted therapy drugs, many of which are already being used to treat NSCLC. Targeted drugs that are approved for use in other cancer types are now being studied in NSCLC that have a change in the RET gene. These drugs include sunitinib, sorafenib, vandetanib, and cabozantinib.

Brain metastases: Brain metastases are a common problem in people with lung cancer and often result in worse outcomes. Whole brain radiation is the usual treatment and can have certain long-term side effects. For people with limited spread of lung cancer to the brain, newer radiation techniques, like SRS, allow for only the specific tumor to be treated with radiation while sparing the rest of the brain. This type of radiation has fewer side effects and is still effective in treating the cancer.

A new drug, AZD3759, is being tested in early clinical trials and shows promising results in people with NSCLC with an EGFR gene change and spread to the brain. The drug seems to be able to cross the blood-brain barrier.

Another investigational oral drug, epitinib, a kinase inhibitor, has also shown some encouraging results in treating brain metastases in NSCLC patients with the EGFR gene change.

Maintenance therapy

For people with advanced lung cancers who get chemotherapy, combinations of 2 chemo drugs (sometimes along with a targeted drug) are typically given for about 4 to 6 cycles. Some studies have found that with NSCLC cancers that have not worsened on treatment, continuing treatment with a single chemo drug such as pemetrexed or with a targeted drug beyond the 4 to 6 cycles may help some people live longer. This is known as maintenance therapy. A possible downside to this continued treatment is that people may not get a break from treatment side effects. Maintenance therapy is recommended more often now, but it is not an option for some people whose cancer is not under control or who are in poor health.

Immune treatments

Researchers are developing immunotherapy drugs that can help a person's immune system fight the cancer.

Immune checkpoint inhibitors: Cancer cells can sometimes avoid being attacked by the body’s immune system by using certain “checkpoints” that normally keep the immune system in check. For example, cancer cells often have a lot of a protein called PD-L1 on their surface that helps them evade the immune system. New drugs that block the PD-L1 protein, or the corresponding PD-1 protein on immune cells called T cells, can help the immune system recognize the cancer cells and attack them. Some of these drugs are now approved for use in advanced NSCLC.

Studies are currently evaluating if giving an immunotherapy drug along with radiation therapy in people who can't have surgery, can improve shrinkage of the tumor and maybe help people live longer.