All lung cancer patients should be screened for MET amplification/overexpression before determining a treatment plan, a new study led by researchers at Rochester, Minn.-based Mayo Clinic suggests.
Among a study involving 81 lung cancer patients, researchers found several cases that were not responsive to chemotherapy. In each of those cases, the cancers were positive for PD-L1 — a protein that allows some cells to evade attack from the immune system.
"We then tried treating these patients with anti-PD1 immunotherapy to relieve PD-L1 mediated immune suppression, however this treatment also failed," said Zhenkun Lou, PhD, lead study author and cancer researcher at Mayo Clinic.
To further investigate why the lung cancers were not responding to treatment, researchers used cell line animal models and patient tissue samples. The findings, published June 7 in Cancer Discovery, found that in those specific cases, the cancer exhibited MET oncogene amplification, "which creates a hostile environment for immunotherapy," Dr Lou said.
Given the findings, Dr. Lou and team concluded MET oncogene amplification would be considered when determining a treatment strategy for lung cancer patients.
"Our study suggests that patients with a MET oncogene amplification will not respond to immunotherapy alone and will require treatment with a combination of a MET inhibitor together with immunotherapy," Dr. Lou said.