Transcript: So, what is a specialist or sub-specialist? Specialists and subspecialists are doctors who specialize in specific internal systems, such as respiratory, gastrointestinal, and/or disease areas. A few examples of specialists include surgeons, endocrinologists, cardiologists, pulmonologists, dermatologists, anesthesiologists, pediatricians, and geriatricians. Cancer specialists often administer chemotherapy, immunotherapy, and biological treatments and work with radiation oncologists and surgeons to care for cancer patients. Subspecialists are doctors who specialize in a specific aspect within their area of study, for example, neuro anesthesiologists,