Evolution of Lung Cancer Treatment from Classical Chemotherapy to Advanced Immunotherapy

Lung cancer is the second most common cancer across the globe. According to SEER (Surveillance, Epidemiology, and End Result), the survival rate of non-small-cell lung cancer (NSCLC) is 28% and small-cell lung cancer (SCLC) is 7%. The standard care of treatment for such a deadly disease includes surgery, radiation therapy, and chemotherapy. Among these, chemotherapy is a painless treatment procedure that uses chemically formulated drugs and biotic compounds to minimize the proliferation rate of cancer cells. However, interaction of the chemotherapeutic drug with the target, insufficiency of the drug for the developing tumour, and chromosomal mutations that cause drug resistance make chemotherapy more challenging. The side effects of chemotherapeutic drugs are also an important point to be considered. Hence in recent years, researchers started investigating on therapies that could enhance human immune system. This led to the discovery of immunotherapy and usage of monoclonal antibodies to block immune checkpoints, thereby enhancing the migration of T cells towards cancer cells. This chapter elaborates various chemotherapeutic drugs used in different stages of lung cancer, the mechanism of action, and the effect of these drugs on cancer cells. The chapter discusses the emergence of new therapeutic strategies like anti-angiogenic therapy, targeted therapies, and combination therapies to interrupt cancer progression.