Evolving Role of Immunotherapy in Lung Cancer

Immunotherapy has revolutionised the treatment paradigms in lung cancer, offering new ray of hope to patients and significantly improving survival. Lung cancer is the most common cancer world-wide and leads to highest number of cancer related deaths. Treating lung cancer was difficult in the past as there were limited options of chemotherapy and radiotherapy and very few patients became eligible for surgery.

Advancements in medical science has led to discovery of battery of drugs grouped as immunotherapy, which works by harnessing the power of the body's immune system to recognize and attack cancer cells, thus providing newer modality for treating this disease.

One of the important immunotherapy drug groups for treatment of lung cancer are immune checkpoint inhibitors. These drugs target specific proteins on immune cells or cancer cells, effectively releasing the brakes on the immune system and allowing it to launch a stronger attack on cancer cells. The immune system has specific proteins that act as checkpoints on immune cells and regulate immune responses thus preventing its inadvertent overactivation which could lead to these immune cells harming our own normal cells leading to autoimmune diseases. However, cancer cells are smarter and can exploit these checkpoints to evade detection and destruction by the immune system. Immune checkpoint inhibitor drugs work by blocking these checkpoints, thereby releasing the shackles leading to the immune system to recognize and attack cancer cells more effectively. Pembrolizumab, nivolumab, and atezolizumab are among the checkpoint inhibitors approved for the treatment of lung cancer.