A retrospective comparison between different stage classifications for nasopharyngeal carcinoma

From 1984 to 1987, 659 patients with untreated nasopharyngeal carcinoma (NPC) were investigated by computed tomography of the nasopharynx and skull base, and fibreoptic nasopharyngoscopy. Thirty-one patients presenting with distant metastasis were treated palliatively; 628 were treated with intent to cure. Prospective staging was performed for the Ho's classification but since all T- and N-stage data required for staging according to the Huang's, the Changsha and the UICC classifications were recorded and stored in a computer database, retrospective staging according to these classifications could be accurately performed. Ho's classification was concluded to be the best in view of highly significant differences between the overall stages in survival and between N-stages in distant metastasis. The number of prognostically distinct overall stages and N-stages was greatest for Ho's classification. Huang's T-stage classification was superior, however, because it emphasized the significant adverse effect on local tumour control of cranial nerve(s) palsy (Tn) and intracranial tumour extension (Tc). Changsha and UICC classifications were demonstrably less powerful in predicting NPC prognosis. Multiple sites of involvement within the nasopharynx by NPC had no adverse influence on local tumour control. The grouping together of both soft-tissue and skull-base lesions into Changsha's T3 has been shown to be unjustified because of significant differences in local failure.