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| Molecular test helps guide treatment for lung cancer BOSTON – September, 2004 The Harvard Medical School - Partners HealthCare Center for Genetics and Genomics (HPCGG) has begun to offer a test that gives doctors a valuable new tool to guide the treatment of certain lung cancers. The test – known as EGFR Kinase Domain Sequencing – was developed in cooperation with the pathology laboratories of Brigham and Women’s Hospital and Massachusetts General Hospital, and detects mutations in a critical part of the gene called epidermal growth factor receptor (EGFR). The gene mutation is present in a subset of non-small cell lung cancers, most commonly adenocarcinomas and bronchoalveolar carcinomas arising in nonsmokers. When the mutation is present, it is associated with a response to the anti-cancer drug Iressa (gefitinib). Iressa works by blocking the function of the mutant EGFR protein that these cancer cells need to survive and proliferate. Last April, two teams of investigators – one led by Thomas Lynch, MD, and Daniel Haber, MD, PhD, at Massachusetts General Hospital, and one by Bruce Johnson, MD, William Sellers, MD, and Matthew Meyerson, MD, PhD, at the Dana-Farber Cancer Institute – discovered the molecular marker that identifies lung cancer patients whose tumors will respond to Iressa. Until then, doctors had been unable to understand why Iressa caused tumors to shrink significantly in only 13.6 percent of patients, even though some of those responses were rapid and dramatic. The discovery of the EGFR mutation provided the answer. Now, less than six months after the gene mutation discovery, the HPCGG Laboratory has prepared a molecular test to screen lung cancer tumors for the mutation. The test, which takes approximately two weeks to complete, involves extracting DNA from a tumor tissue sample. The test is significant because it gives doctors the information they need to decide which patients may benefit from Iressa at the earliest possible time, within weeks of diagnosis. The MGH and DFCI investigators have applied for a patent for the test and are in the process of licensing the EGFR test to a commercial diagnostic partner so that it can be performed throughout the country and eventually the world. In the meantime, HPCGG will continue to offer the test through its Cambridge lab. “For one out of ten patients whose tumors test positive for the mutation, this test unlocks the door to hope. Our goal is to get the test into the widest use quickly,” said Raju Kucherlapati, PhD, scientific director of HPCGG. Kucherlapati explained that HPCGG has the capacity to conduct approximately 100 tests per month, which he expects will meet the immediate demand. “This is an extraordinary example of moving a significant scientific discovery from bench to bedside in less than six months,” Kucherlapati continued. According to Lynch, who is the director of the Thoracic Oncology Center at the Massachusetts General Hospital Cancer Center, the availability of the test is a textbook example of the potential of genomic medicine. “We are moving toward the day when the science of genomics will inform therapeutic decisions as well as uncover new targets of therapy. Now with the advent of testing for EGFR mutations in lung cancer patients, we can select patients for therapy based on a firm understanding of which treatment will target the cancer most effectively.” “The sequencing of EGFR in lung cancers is a monumental step forward for our patients,” said Bruce Johnson, M.D., director of the Lowe Center for Thoracic Oncology at Dana-Farber. “If information from this initial finding is confirmed, patients with these mutations will be able to be treated for a year or more with a pill administered once daily, a dramatic advance from the use of conventional chemotherapy.” Lung cancer is the leading cause of cancer death in the United States, responsible for approximately 160,000 deaths each year. Treatment options have been limited, and many patients die within a few months of being diagnosed. Iressa was approved by the FDA last May, but only for use after other drugs have failed. Many doctors now believe that in the future the new test may allow them to use Iressa right away for patients whose tumors have the gene mutation. Oncologists who wish to access the test for their patients can do so through the HPCGG website. Harvard Medical School and Partners HealthCare created the Center for Genetics and Genomics with the mission to promote genetics and genomics in research and clinical medicine at the Partners HealthCare and Harvard Medical School-affiliated institutions. Click here for more in-depth information about the Laboratory for Molecular Medicine.
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