Lung cancer is the fifth most common cancer in India. And of the two types of lung cancers — Small Cell and Non-Small Cell (NSCLC), the latter has seen a rise.
NON-SMALL CELL LUNG CANCER (NSCLC)
Lung cancer is the fifth most common cancer in India. And of the two types of lung cancers — Small Cell and Non-Small Cell (NSCLC), the latter has seen a rise. NSCLC accounts for 85 per cent cases of lung cancer. And the worrying bit is that it is not limited to smokers alone; many non-smokers and women are increasingly being diagnosed with this type of cancer. The causes for this could range from passive smoking to genetic mutations. But there is no reason to panic as there have been major developments over the last few decades with the management of NSCLC (adenocarcinoma).
All patients with metastatic NSCLC are first screened for potential mutations such as EGFR, ALK and ROS, commonly seen in non-smokers, women and Asians.
Patients with these positive mutations can be treated with oral Tyrosine Kinase Inhibitors (TKI) initially rather than intravenous chemotherapy. TKI’s are small molecules given as tablets which control and stop the cancer cell growth. Those patients with these mutations have better benefits and outcomes with TM than conventional chemotherapy. The drugs used commonly are Erlotinib and Geftinib for EGFR positive patients and Crizotinib for ALK positive patients.
Patients are prescribed a tablet to be taken everyday and are managed for side effects and are evaluated at periodic intervals (every 3 months) with CT/PET scans to assess response. Those patients who do well are continued with TKI till progression. Those patients who do not have mutations are treated with chemotherapy (usually two drugs) for a fixed period, i.e 4-6 cycles and further, one of the chemotherapy drugs is continued till response is sustained. This ensures continuous delivery of chemotherapy and control of disease and is called as maintenance therapy.
IMMUNOTHERAPY, A MILESTONE IN TREATMENT METHODS
Immunotherapy is a type of cancer treatment designed to boost the body’s natural defenses to fight the cancer. Many cancers use path-ways to evade the body’s immune system. Blocking these pathways with specific anti-bodies called immune checkpoint inhibitors allows the body’s immune system to respond to the cancer. Nivolumab and Pembrolizumab are two drugs approved for use in metastatic NSCLC. Nivolumab has demonstrated better responses and survival as compared to chemotherapy in pre treated patients.
ONGOING WORK TO OPTIMISE TREATMENT
Treatment of Stage IV NSCLC has become personalised leading to better outcomes and improved survivals with improvement in quality of life. Despite the breakthroughs, disease recurs in most patients and further work is needed to optimise outcomes.
