Introduction:
Lung cancer is the leading cause of death in men in India and fourth leading cause of death in men and women combined. Main reason for the incidence of lung cancer is exposure to tobacco smoke and in some in cases exposure to asbestos (rare these days),arsenic,polycyclic hydrocarbons,radon gas exposure. In selected cases the five year survival ranges between 20 to 80 percent based on the stage. In general the five year survival rate for lung cancer after diagnosis is sixteen percent. The risk is directly related to number packs smoked per day multiplied by number years of smoking it is termed as pack years of smoking.
Symptoms:
Common symptoms at presentation are cough,blood in cough or sputum ,breathlessness and chest pain. Lung cancer sometimes secreted certain substances which can cause different symptoms at distant sites (paraneoplastic syndromes).
Diagnosis:
When some one comes to a doctor a detailed history and physical exam are key to the diagnosis.Basic investigations include chest X-ray followed by a CT and then biopsy, which reported by a pathologist who does various tests on tissues to report it. These include H&E staining, IHC, mutation analysis, molecular analysis when available.In a tertiary referral centre like our Continental Cancer Centre we also have advanced imaging and intervention technologies like PET-CT Scan, EBUS (Endobronchial Ultrasound). Once the patient is diagnosed it is also important to stage the disease this so crucial that entire treatment plan is dependent on it. According to stage and tumour characteristics further tests may be required to rule out brain and bone metastasis. Lung cancer is stages using T(tumour size and local extent),N (involvement of nodes which will be locoregional extent) , M (Distant spread).
Treatment:
Treatment of Non-Small cell lung cancer is based on staging stages I and II surgery is the mainstay of treatment, Radiosurgery can be offered in certain cases. Tumours larger than 4cm may require chemotherapy after surgery. Some cases may require radiation after surgery based on pathology report after surgery. In stage IIIA and IIIB disease the rule of thumb is all the diseases classified as N2, N3 (advanced nodal stages) receive Chemo-radiation and rest of the resectable diseases go for surgery if not they receive Chemo-radiation and these are decisions taken up in multidisciplinary meetings. In stage IV disease chemotherapy is the mainstay of the treatment.In select stage IV diseases Chemo-radiation can still be offered in limited metastatic disease.In lung cancer treatment lung function tests and patients ability to tolerate surgery is considered first.
Treatment of Small cell lung cancer is based on limited stage disease and extensive stage disease. This disease requires Chemotherapy ,Radiation to lung and prophylactic cranial irradiation.Though response rates are good but the survival rates are poor with only four percent of patient alive at two years.