Modifier -26 would be used when you are billing for the pathologist's services and the lab's (facility's) services will be billed by a separate entity (using -TC) modifier. If the pathologist is employed by the facility and the global of the lab service is being billed then no modifier would be appropriate. The use of -26 can also apply to cytology codes, molecular pathology, and perhaps other codes, in addition to surgical pathology.
Hope this helps,
Karen
CCS-P, CPC, CPB,CPMA,CPC-I