CTC Count Useful for Monitoring Treatment Response and for Predicting Survival of Lung Cancer and Mesothelioma Patients
Researchers at Cancer Research UK have validated that a simple blood test to “count” the number of circulating tumor cells (CTCs) in a lung cancer patient can predict the patient’s survival. In addition, the researchers concluded that by identifying CTCs in a lung cancer patient’s bloodstream undergoing treatment, oncologists can monitor the patient’s response and adjust the treatment to ensure optimal efficacy. Currently, there are no effective non-invasive methods for early detection or treatment monitoring for either lung cancer or mesothelioma.
While 80% of lung cancers are caused by cigarette smoking, mesothelioma is a serious pulmonary cancer that occurs in individuals exposed to airborne asbestos fibers. Asbestos is a known carcinogen and is also proven to cause asbestosis and some cases of lung cancer. While pleural mesothelioma is not classified as a lung cancer according to the medical definition, the treatments between the two are often very similar.
The researchers, led by Caroline Dive, PhD, Paterson Institute for Cancer Research, studied blood samples from 101 non-small cell lung cancer (NSCLC) patients, both before and after undergoing one cycle of chemotherapy. After counting the CTC’s in the patients’ samples, those patients with five or more CTCs had an average overall survival of just 4.3 months. This was significantly worse than patients with fewer than five CTCs who survived almost twice as long, for an average of 8.1 months.
The findings, reported in the Journal of Clinical Oncology, suggest that the ability to count and evaluate CTCs is a breakthrough for physicians when monitoring the effectiveness of their patient’s treatment. If a patient is not responding to a treatment, for example, and CTC numbers begin to rise, the doctor can quickly adjust to a more aggressive option. The researchers noted that currently there are no tests available for determining responsiveness.
Dive said if they can learn more about CTC counts “before a patient has chemotherapy and then again later if the cancer returns, we may be able to learn more about the processes that lead to drug resistance, and ultimately develop new drugs.”
Scientists at Massachusetts General Hospital’s cancer center have partnered with Johnson & Johnson for marketing a microchip to use as a tool to count CTCs which will provide physicians with a non-invasive, reliable method for early detection of cancer, for the ongoing monitoring of changes in the cancer cells during treatment and for developing personalized treatments for patients.
Treatment targeted to a particular patient optimizes the potential for success of the treatment, limits experimental treatments, and also provides the patient with more choices for cancer therapy. Treatment for mesothelioma can differ dramatically across patients and mesothelioma is best treated through personalized care targeted to a patient’s unique mesothelioma characteristics.