Yes there are a handful of older stations in the east starting with K. I recall KYW in Philadelphia is another.
And a handful in the west start with W. Such as WACO radio in Waco, Texas. I think all such exceptions are very old radio stations which were assigned call letters before the current system was set up.
Neighbor up the road is a radio ham and pilot and we chat a lot about SW listening and stuff; pretty good with the history of radio.