A simple blood test that can detect the presence of the enzyme (protein) telomerase may enable the diagnosis of early-stage lung cancer when it is most curable, as reported by physicians at the Greenebaum Cancer Center at the University of Maryland.
Lung cancer is the leading cause of cancer deaths in the United States. Although 65% of lung cancer is curable when treated in early stages, the majority of patients are diagnosed after their cancer has progressed, which greatly reduces their chances for a cure. Thus, focused efforts in research are aimed at early detection, so that patients can be treated when their disease is highly curable.
Telomerase is an enzyme that is responsible for lengthening genetic sequences called telomeres. Telomeres are found at the ends of chromosomes (structures consisting of DNA) and are shortened at each cell division. Normal cell death occurs when telomeres are decreased to a specific length. Excessive telomerase prevents the normal shortening of telomere sequences, which ultimately prevents cell death. When normal cellular death is prevented, the result is cancer or a benign tumor.
The physicians from Greenebaum Cancer Center report that telomerase can be detected in 75% of patients with lung cancer, even those with early stage disease. These physicians also predict that telomerase may be utilized to follow the course of the disease and predict the risk of recurrences and/or detect early recurrences that are not detectable through current methods.
The telomerase blood test is still being refined in clinical trials but may emerge as an important diagnostic tool for lung cancer in the future, with the hope of improving cure rates through early detection. Future trials may include this blood test in combination with other diagnostic tests to further improve detection of lung cancer in the earliest stages. Patients with lung cancer or those at risk for developing lung cancer may wish to speak with their physicians about the participation in clinical trials further evaluating the telomerase blood test.