The emergence of molecular diagnostic testing in lung cancer offers new hope for patients battling the number one fatal cancer in the United States. After a decade of biomarker testing in lung cancer, a uniform approach for testing for the EGFR mutation and ALK rearrangement along with the availability of targeted therapies offer lung cancer patients the chance for improved quality of life and more time with their loved ones.
An evidence-based guideline has been developed that establishes recommendations for EGFR and ALK testing, which helps to guide targeted therapies. The guideline was developed by the College of American Pathologists, the International Association for the Study of Lung Cancer (IASLC), and the Association for Molecular Pathology. It was published in Archives of Pathology & Laboratory Medicine (2013; doi:10.5858/arpa.2012-0720-OA), Journal of Thoracic Oncology (doi: 10.1097/JTO.0b013e318290868f), and The Journal of Molecular Diagnostics (2013; doi:10.1016/j.jmoldx.2013.03.001).
“The key recommendation of the guideline, and perhaps most important to lung cancer patients, is that all patients with advanced lung adenocarcinoma should be tested for EGFR and ALK abnormalities, that would qualify them for tyrosine kinase inhibitor therapy, regardless of their clinical variables, such as smoking history, gender, or ethnicity,” said Marc Ladanyi, MD, attending pathologist in the Molecular Diagnostics Service at Memorial Sloan-Kettering Cancer Center in New York, and IASLC member.
Similar to the testing done in breast cancer, matching a cancer patient’s molecular profile with the appropriate targeted therapy provides individualized treatment options. The guideline answers important clinical questions, including when testing should be performed, how the testing should be performed, if other genes should be routinely tested in lung cancer, and how molecular testing of lung cancer should be implemented.
“In the US up to 20% of patients with lung adenocarcinoma, the most common type of lung cancer, will test positive for one of the two biomarkers,” said Philip T. Cagle, MD, FCAP, Medical Director, Pulmonary Pathology in the Department of Pathology and Genomic Medicine at The Methodist Hospital in Houston, Texas, APLM editor, and CAP member. “It is critical to identify these patients because they stand to benefit more from new targeted drugs than from conventional chemotherapy, and with fewer side effects.”
In an era of precision medicine, the guideline provides recommendations for pathologists, oncologists, and other cancer health professionals on the current state-of-the-art practices for the molecular testing of lung cancer.