In 1977, The American Joint Committee for Cancer Staging and End-Results Reporting (AJC) revised its 1972 staging system for supraglottic cancer of the larynx. These changes included the following: (1) reclassifying T1b carcinomas as T2 carcinomas, (2) reclassifying extension onto the medial wall of the piriform sinus or postcricoid mucosa as T3 carcinomas rather than T4 carcinomas, (3) restructuring of the N classification, and (4) changing the classification of T4 NO carcinomas from stage III to stage IV. To correlate these changes with prognosis, the cases of 178 patients with supraglottic laryngeal cancer who were treated at the University of Virginia Medical Center, Charlottesville, from 1955 to 1976 were reviewed. Each case was classified using both the 1972 and 1977 AJC TNM system. Using the 1972 staging system, the following determinations were made regarding our patient population: stage I, 43 patients; stage II, 15 patients; stage III, 116 patients; and stage IV, four patients. Using the 1977 cancer staging system, the following determinations were made: stage I, 19 patients; stage II, 37 patients; stage III, 37 patients. six specific changes in the TNM classification system seem to be justified. However, the upstaging of T4 NO supraglottic cancers from stage III to stage IV seems to be unjustified; T4 NO cancers should be returned to the state III grouping.