For decades, the hallmark of medical treatment for cancer has been intravenous cytotoxic chemotherapy. These drugs target rapidly dividing cancer cells and normal cells, leading to hair loss, vomiting and low blood cells. In the past decades, however, a dramatic shift in cancer therapy has occurred, targeted therapies are now a component of treatment for many types of cancer, including breast, colorectal, lung, and pancreatic cancers, as well as lymphoma, leukemia, and multiple myeloma. Targeted therapies, which include monoclonal antibodies and small molecule inhibitors, have significantly changed the treatment of cancer over the past 20 years. These drugs are now a component of therapy for many common malignancies, including breast, colorectal, lung, and pancreatic cancers, as well as lymphoma, leukemia, and multiple myeloma.

The mechanisms of action and toxicities of targeted therapies differ from those of traditional cytotoxic chemotherapy. Targeted therapies are generally better tolerated than traditional chemotherapy.