Although I don't know the specific salary for gyn onc, I do know that it is one of the best paid OB/GYN subspecialties. They make more than medical oncologists (which is a completely different specialty through medicine, not OB/GYN) because it is a surgical specialty. There are also not that many gyn oncs out there. I would geuss starting is in the 200,000-300,000 range depending on area and practice.