Traditional treatment offers small advantage for people without a specific gene mutation, study says
TUESDAY, April 8, 2014 (HealthDay News) -- Cancer specialists have been unsure about how best to treat certain patients with an advanced form of lung cancer.
Now, a new analysis of existing research finds that traditional chemotherapy outperforms newer, targeted treatments in delaying the time until the cancer worsens for these patients. However, chemo doesn't extend their survival, the review found.
Patients with non-small cell lung cancer make up 85 percent to 90 percent of lung cancer patients. Some of them have a mutation in a gene that makes their tumors more responsive to medications known as epidermal growth factor receptor tyrosine kinase inhibitors. But most patients with non-small cell lung cancer do not have this mutation, and doctors have been unsure whether this larger group of patients should get chemo or the targeted medication.
"In our opinion, conventional chemotherapy is a better treatment option for patients if patients are in suitable condition for chemotherapy because it is associated with delayed tumor progression and higher rate of tumor shrinkage," said review co-author Dr. Dong-Wan Kim, of the department of internal medicine at Seoul National University Hospital in South Korea.
About 10 percent of patients in the West and half of Asian patients have the mutation, according to the study, published in the April 9 issue of the Journal of the American Medical Association.
People with advanced non-small cell lung cancer typically survive for only 10 to 12 months, said Dr. Suresh Ramalingam, a professor of medical oncology at Emory University's Winship Cancer Institute in Atlanta.
The authors of the new analysis looked at 11 prior studies that included over 1,600 patients who didn't have the mutation.
Overall, half of those on traditional chemotherapy lasted 6.4 months or more before their cancer worsened, the study found. But that midpoint, or median, of progression-free survival was just 4.5 months for those who took medications that help lung cancer patients with the mutation -- erlotinib (Tarceva) and gefitinib (Iressa).
However, the length of time patients lived after the treatment wasn't appreciably different between the two groups.
Still, in this group of patients, even in the late stages of the disease, "chemotherapy appears to have a modest advantage," Ramalingam said.
Do the treatments matter if they don't extend lifespan? Yes, said Ramalingam.
"Improvements in outcome for lung cancer have mostly come in incremental steps," said Ramalingam. "An improvement in survival by a few months is still valuable for what was considered an untreatable disease not too long ago."
Because patients weren't randomized to one treatment or the other, the study cannot be considered conclusive.
Also, the analysis doesn't examine side effects. However, Ramalingam said the side effects of the treatments are known "and can be managed with appropriate supportive care measures in both settings."
Traditional chemotherapy has a wide variety of side effects, including nausea, hair loss and other problems. The targeted drugs cause side effects like skin rashes (which can become infections), diarrhea and fatigue.
As for expense, both treatments -- traditional chemotherapy and the alternate " targeted" form of therapy used for the comparison -- cost about the same, Ramalingam said.
Scientists need to continue developing different treatments for non-small cell lung cancer patients based on their genetic makeup, especially those who don't have the "treatable target mutation," Ramalingam said.
Testing for the mutation is becoming more common because treatment can be individualized for patients who have it. Last year, the College of American Pathologists, the International Association for the Study of Lung Cancer and the Association for Molecular Pathology recommended that doctors use a test for the mutation to guide treatment for patients with advanced lung cancer.
For more about lung cancer, see the U.S. National Cancer Institute (http://www.cancer.gov/cancertopics/pdq/treatment/non-small-cell-lung/Patient/page1 ).
SOURCES: Dong-Wan Kim, M.D., Ph.D., associate professor, department of internal medicine, Seoul National University Hospital, South Korea; Suresh Ramalingam, M.D., professor, hematology and medical oncology, and director, division of medical oncology, Winship Cancer Institute, Emory University, Atlanta; April 9, 2014, Journal of the American Medical Association