Oncology is a medical specialty that studies the prevention, diagnosis and treatment of cancer. Cancer is a group of diseases involving abnormal cell growth which have the potential to invade or spread to other parts of the body. An oncologist is a doctor who diagnoses and treats people with cancer. Since most cancers are treated with a combination of therapies you could see several different kinds of oncologists during the course of your treatment – a medical, surgical and/or radiation oncologist. Southern New Hampshire Health offers compassionate, expert care by board-certified hematologists/oncologists at Foundation Hematology/Oncology.