Nurse Doctor - S8-E7
Revealing mistake: While Charles is in the shower stall Hawkeye and BJ take his bottle of Vichy water, and when Charles steps out of the stall The Nurses outside the tent whistle, but we can see through the stall's openings that Charles is wearing something.
Answer: It is actually Cencompac for Central Command of the Pacific. It is like the headquarters for all military activity in the Pacific Region (Japan, Korea, Okinawa, etc. The newer version of that is United States Pacific Command (USPACOM).
EMTurbo
And the abbreviations were used mainly by the Navy. Especially CENCOMPAC.
Https://en.wikipedia.org/wiki/United_States_Indo-Pacific_Command.