Physicians count on catching cancer early as one way to increase patients’ odds against the disease. In some cancers caught in the earliest stages, the vast majority of patients beat the disease.
Dan Raz (Photo by p.cunningham)
The outlook is not necessarily so optimistic for patients with stage 1 lung cancer. But a new genetic test may help change that. Two large, international studies showed that the test successfully predicts survival in early-stage lung cancer patients. Physicians may be able to use the test to tailor therapy to individual patients’ disease, making treatment more effective.
The results, co-authored by Dan J. Raz, M.D., now assistant professor in the Department of Surgery at City of Hope, appeared online in The Lancet Jan. 27. Raz joined City of Hope in January, and was part of the University of California, San Francisco (UCSF), team pursuing the project. Senior authors were UCSF surgeons Michael J. Mann, M.D., and David M. Jablons, M.D.
“This is really the first test that has been validated in such a large, diverse population,” said Raz, part of the Division of Thoracic Surgery. “It’s one step to improve survival for early-stage patients.”
Lung cancer is the No. 1 cancer killer in the U.S. and worldwide, Raz noted. The American Cancer Society estimates that more than 226,000 people in the U.S. will be diagnosed with the disease this year, and more than 160,000 will die from it.
Labeling a tumor as stage 1 means that doctors found no evidence that cancer spread beyond the lung. Yet lung cancer too often returns after surgery. And in those cases, a patient’s prognosis is almost universally poor.
According to Raz, who was instrumental in developing the genetic test during his UCSF residency, only 60 to 70 percent of stage 1 patients survive five years after diagnosis.
The test assesses samples of cancerous tissue for the activity of 14 genes linked to cancer. It could single out patients with aggressive disease so physicians can deliver additional treatment to combat remaining cancer cells that are currently undetectable.
The Lancet paper focused on more than 1,400 patients in the U.S. and China with non-squamous, non-small-cell lung cancer, the most common subtype of the disease.
All participants had undergone surgery to remove their tumors. Researchers analyzed tumor tissue using the test and compared the test’s predictions with records of patient outcomes.
They found that more than 70 percent of patients identified as low-risk were alive five years later. Patients classified as intermediate-risk had a survival rate less than 60 percent. And less than half of high-risk patients survived five years.
The test already is available from Mountain View, Calif.-based Pinpoint Genomics, which partially supported the work, but further research is needed to determine which treatments will best help high-risk patients.
“This is a very exciting development to help with early-stage lung cancer patients, because it’s the first of its kind. It’s certainly not the last thing, but it’s an important first step,” Raz said.
At City of Hope, Raz will continue his research seeking ways to predict how early-stage lung cancer patients will respond to treatment and fare after it. He also plans to collaborate with other scientists to develop new treatments.