Every cancer starts with a single cell that has the ability to evade the immune system’s surveillance. Continuous excessive growth of the cell results in tumor generation and progression. Cancer doesn’t happen because of the immune system’s inability to fight. It happens because of the cancer cells’ ability to stay invisible to the immune system or suppress its fighting functions in the tumor micro environment. Hypothetically, a cure can be accomplished if the patient’s immune system is taught to effectively identify and kill the elusive cancer cells that evade or repel the immune cells. As a general concept “immunotherapy” governs different strategies and treatment modalities to accomplish this feat.