USNEWS：联合疗法是治疗肺癌的下一波疗法吗？

THE AMERICAN CANCER Society reports that lung cancer is the second most common cancer in America today, constituting about 14 percent of all new cancer diagnoses. That means about 234,030 new cases of lung cancer are expected to be diagnosed in 2018, and about 154,050 people are expected to die of the disease this year, making it the leading cause of cancer death.

The problem with lung cancer is that it’s often diagnosed at a later stagewhen standard treatments such as surgery, chemotherapy and radiationaren’t as effective. But that reality may be changing as newer treatments – in particular a class of drug therapies called immunotherapies – are becoming more widely available to combat metastatic disease.

The ACS reports that immunotherapy medications “stimulate a person’s own immune system to recognize and destroy cancer cells more effectively.” They’re currently being used to treat some forms of non-small cell lung cancer, the most common type, accounting for 80 to 85 percent of all lung cancers. These immunotherapies, called immune checkpoint inhibitors, target molecules on immune cells that prevent the cells from attacking cancer cells. These drugs help immune cells “see” cancer cells as dangerous and attack them accordingly. For the past couple of years, these drugs have been helping to extend life for some lung cancer patients, but a new application of them in combination with chemotherapy may well be the next wave in treating advanced-stage lung cancer.

“When somebody is diagnosed with stage 4 lung cancer, the disease has traveled to other parts of the body and the usual approach is to use drug therapy,” says Dr. James Stevenson, an oncologist specializing in lung cancer at the Cleveland Clinic. A single type of chemo drug may be used, or doctors may opt to combine two or three different drugs, depending on the specifics of each case. “Traditionally, we’ve used combinations of chemotherapy drugs because we know these combination drugs, what we call platinum-based combinations, provide more benefit than if you used one drug by itself,” Stevenson says.

Benefit is typically measured by how long the drugs prolong survival, because stage 4 lung cancer “is incurable.” Doctors also measure benefit by whether the patient’s tumors shrink and whether their symptoms improve, “hopefully without too much in the way of side effects so the patient can have a longer life but also a better quality of life. That’s the goal that we look at when treating these patients,” Stevenson says. The overall life expectancy of a stage 4 lung cancer patient is typically measured in months, even with these combined chemotherapy drugs. But it appears that adding immunotherapy to chemotherapy could extend survival for some patients into many more months and sometimes even years.

Researchers still have many questions to answer with regard to how best to use these combination therapies and who the best candidate is for any new drug or therapeutic approach, says Dr. Laurie Carr, associate professor of oncology at National Jewish Health in Denver. “Whenever we have a new therapy in lung cancer, we have to ask ourselves, ‘Is it better to add it to something we’re already using or use it in sequence?'”

She says doctors also must consider whether the potential benefits of adding another drug are worth the risk of additional side effects. Taking three drugs at once “may work better than taking just two, but you’re taking on side effects from that entire combination, not to mention time in the infusion room and cost. So the other question we need to ask is, ‘Are there certain populations or individuals who would do better if we started by combining three drugs together?'”