Hematology represents the branch of internal medicine concerned with illness and conditions of the blood and systems directly related to blood such as bone marrow and lymph nodes. These include clotting disorders, anemia and various defects of the bone marrow and white blood cells. They also treat cancers of the blood and lymph nodes which include Hodgkin's disease, non-Hodgkin's lymphoma and different forms of leukemia. Oncology is also the branch of internal medicine, but it is all about diagnosing and treating cancers. Surgical oncologists and radiation oncologists remove cancers physically or destroy them with radiation. Medical oncologists administer chemotherapy and other forms of medication as part of their treatment. Medical oncologists are usually responsible for diagnosing cancer and determining its type and extent, and they'll coordinate a patient's care in collaboration with surgeons and other practitioners.