New guidelines recommend molecular testing for lung cancer patients
Professional guidelines recommend all patients with advanced-stage lung adenocarcinoma be tested for EGFR and ALK, regardless of clinical history
Personalized medicine is the future of oncology. New targeted treatments can offer prolonged survival and fewer side effects for patients whose tumors have specific genetic alterations. The College of American Pathologists, the International Association for the Study of Lung Cancer and the Association for Molecular Pathology all agree – all lung cancer patients who may be able to benefit from these drugs should undergo molecular testing. That includes lung cancer patients with adenocarcinomas and mixed lung cancers with adenocarcinoma components (but not “pure” squamous, small cell or large cell carcinomas).
Molecular testing, also called genetic profiling, analyzes specific elements of cancer DNA that may be causing the cancer to grow. These mistakes in the genetic code are only found in cancer cells and are not inherited. Targeted therapies hone in on these mistakes to attack cancer cells, resulting in fewer side effects for patients and prolonged life.
Up to 20% of lung cancer patients in the US will have tumors that test positive for the biomarkers EGFR or ALK, and benefit from matching targeted drugs. About 10% of non-small cell lung cancer patients in the US have tumors with EGFR mutations. These patients have shown a 70% response rate to EGFR-targeted therapies, with fewer side effects and longer responses to treatment. Patients with ALK rearrangements (3-7% of NSCLC patients) show a 60% response rate to ALK-targeted therapies, higher than chemotherapy and with fewer side effects.
Targeted drugs, when matched to the right patients, can improve quality of life and prolong it. Yet not all lung cancer patients can benefit from targeted drugs at this time. Lung cancers are very diverse with many different genes causing tumors to grow. Research is ongoing to identify additional genes that drive lung cancer to grow, and to develop new targeted therapies for the 80% of patients who are not EGFR or ALK positive. (Read more about the different molecular types of lung cancers here.)
While we do not yet have additional FDA-approved therapies, many new treatments are being developed in clinical trials for lung cancers with different profiles. Doctors may also expand testing to additional genes such as KRAS, one of the most common types of lung cancers, or may opt for profiling many genes within the tumor to look for potential clinical trials.
Uniting Against Lung Cancer is funding many projects in this area, including a new grant to Dr. Alice Shaw (Massachusetts General Hospital) who is developing treatments for patients with ROS1 mutations. Drs. Aaron Hata (MGH), Zehua Zhu (Dana-Farber Cancer Institute), and Steven Lin (MD Anderson Cancer Center) are improving targeted therapies for patients with KRAS mutations. With your help, we can fund more research that will save lives.
Personalized medicine is the future, and patients are already benefiting from ongoing research. All patients should talk to their doctors about molecular testing. If testing is not recommended, ask why.
Check out our page on Personalized Medicine and Molecular Testing for more information and additional questions to ask your doctor. You can also read a summary of the professional guidelines here.
Reference: Lindeman NI, Cagle PT, Beasley MB, et al. Molecular Testing Guideline for Selection of Lung Cancer Patients for EGFR and ALK Tyrosine Kinase Inhibitors: Guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Arch Pathol Lab Med. doi: 10.5858/arpa.2012-0720-OA.