THURSDAY, May 16 (HealthDay News) -- The U.S. Food and Drug Administration has approved a test designed to detect a faulty gene that's present in about 10 percent of cases of non-small cell lung cancer (NSCLC).

The cobas EGFR Mutation Test, a companion diagnostic to the approved cancer drug Tarceva (erlotinib), detects a mutation in the epidermal growth factor receptor (EGFR) gene, the FDA said in a news release.

Lung cancer is the leading cause of cancer-related death for both men and women, accounting for about 228,000 annual cases in the United States. Some 85 percent of lung cancers are NSCLC, the FDA said.

In approving the new diagnostic, the FDA also sanctioned expanded use for Tarceva as a first-line treatment for people with NSCLC that has spread to other parts of the body and who have the mutated gene, the agency said.

The new diagnostic is produced by California-based Roche Molecular Systems. Tarceva, first approved in 2004, now has three approvals for lung cancer. It's produced by California-based Genentech and New York-based OSI Pharmaceuticals.

More information

The U.S. National Cancer Institute has more about non-small cell lung cancer.