Yes, OC = oral cancer.

CCC is short for "comprehensive cancer center" -- meaning a facility where specialists from a variety of areas (surgeons, chemo docs, radiation docs, etc.) meet as a multidisciplinary team and jointly decide on a treatment plan for each case -- a "comprehensive" approach, as it were. CCCs see a large volume of cases and specialize in cancer, while your local ENT may see only one or two OCs a year (if that) and also takes out tonsils, puts in ear tubes and does nose jobs, among other things.

You'll see references on these boards to NCI-designated comprehensive cancer centers and cancer centers. In this context, the differences between CCC and CC have to do solely with research interests (broader in the case of NCI-designated CCCs), and both do take a multidisciplinary approach to patient care. Institutions apply to the National Cancer Institute for the right to be called "NCI-designated" -- it is a lengthy process that involves a lot of paperwork. About 20 leading US cancer centers are also members of the National Comprehensive Cancer Network; together they devise the treatment protocols that are updated annually and used by hospitals across the country.

You'll find a list of commonly used abbreviations (and their explanations) here. Be sure to check out the main Oral Cancer Foundation site, which has a wealth of information. And remember, there are no stupid questions on these boards, so ask away!