A proposal for classification of oropharyngeal squamous cell carcinoma: Morphology and status of HPV by immunohistochemistry and molecular biology.

The current three-tier grading system (well, moderate and poorly differentiated) used to morphologically classify head and neck squamous cell carcinoma (HNSCC) is inadequate for categorisation of oropharyngeal squamous cell carcinoma (OPSCC) owing to the lack of prognostic value. The aim of this study was to assess the validity of a classification system for OPSCC based on morphology and human papilloma virus (HPV) infection status. Haematoxylin and eosin slides of 121 patients (100 M, 21 F, age range 40-89 years) with OPSCC were reviewed and categorised as histological types I, II and III.