Oncology is the field of medicine that specializes in cancer. There are three main branches of oncology including medical oncology, surgical oncology, and radiation oncology. A medical oncologist is a physician who is trained to diagnose and treat different types of cancers with chemotherapy, immunotherapy, and targeted therapy. Medical oncologists must first undergo training in Internal Medicine prior to a specialization in oncology. At our practice, all Oncologists (cancer doctors) are also Hematologists (blood disorder doctors).