categorical value specification pathologic primary tumor stage for lung according to AJCC 7th edition A categorical value specification that is a pathologic finding about one or more characteristics of lung cancer following the rules of the TNM American Joint Committee on Cancer (AJCC) version 7 classification system as they pertain to staging of the primary tumor. TNM pathologic primary tumor findings are based on clinical findings supplemented by histopathologic examination of one or more tissue specimens acquired during surgery.