How Cancer Treatments are Supposed to Work

Cancer treatments fall into five major categories: surgical removal, chemotherapy, radiation, immnuotherapy, and small molecules. The first, surgery, is the oldest and most straightforward. Find the tumor and cut it out. This can cure the patient if the disease has not spread to other areas of the body. Chemotherapy, or cytotoxic (cell-killing) agents are still the foundation of most cancer treatment regimens. These chemicals come in many forms, but they have similar ways of working in the body. A common misconception is that chemo kills cells directly. Rather, the agent damages the DNA of a cell, and when the cell attempts to divide, this triggers a self-destruct program. Radiation also damages DNA preventing cancer cells from dividing. The main problem with chemo and radiation is that they are toxic to all cells, both tumor and normal cells are affected. Cells with rapid turnover rates like hair, intestinal lining, and white blood cells to fight infection are devastated by these therapies. This "scorched earth" defense often results in a patient who is malnourished, anemic, and prone to infection in addition to the cancer.