Lung cancer is the most frequent cancer in the world and is the leading cause of cancer-related deaths. In India too, the incidence is high. Approximately 2.5 million people are affected worldwide and over 70,000 in India every year. The cause of lung cancer is environmental, most of which is due to smoking. Hence it is preventable in many cases. They are only very rarely hereditary and never contagious- i.e. they do not spread by physical contact. Unfortunately, the incidence in non-smokers is also rising. Let's see what Dr. Jacob George, Consultant Medical Oncology, Manipal Hospital, Goa has to say on this.
Lung cancers are aggressive tumours. Patients presenting with advanced-stage disease are common and the risk of recurrence after treatment of early-stage cancer is also high. Like other cancers, lung cancers are treated with surgery, radiation, and systemic therapy [which includes chemotherapy]. Improvement in tools that aid in diagnosis like PET-CT scans, molecular testing, and surgery [eg. minimally invasive techniques like Robotic surgery, VATS] and radiation therapy [stereotactic radiation] have improved outcomes as well as decreased complications of treatment. Patients who are diagnosed to have early-stage lung cancer have a chance of cure, after standard surgical resection. Unfortunately, the risk of recurrence is still high with surgery alone.
Therefore, adjuvant treatment is required in the form of chemotherapy. Patients with tumours that are inoperable and patients with operable tumours who are unfit for surgery are treated primarily with radiation therapy. Advanced lung cancer is incurable and the treatment remains palliative. The mainstay of treatment is systemic therapy. The survival of patients without treatment is only a few months and modestly better with conventional treatment including chemotherapy. However, in the past decade or two, with the progress of molecular biology, newer treatment modalities have come into the treatment landscape-mainly targeted medicines and immunotherapy.
Modern anti-cancer treatment mandates compulsory molecular testing which has helped to individualize cancer treatment according to the tumour biology. This has resulted in superior outcomes - not only better control of disease but also significant improvement in survival. These newer treatment modalities also have a role to play in early-stage disease as adjuvant treatment along with surgery, radiation, and chemotherapy. The addition of these drugs in early-stage lung cancer has decreased the recurrence and thus cured more patients afflicted with this aggressive cancer.