Immunohistochemical localization of human papilloma virus in conjunctival neoplasias: A retrospective study

BACKGROUND: The extent of association of human papilloma virus (HPV) in human conjunctival neoplasias has been debated in studies originating from different parts of the world, but no substantial evidence has been generated on Indian subjects. This prompted us to carry out a retrospective study on conjunctival neoplasias diagnosed over the past 12 years. MATERIALS AND METHODS: Histopathological and immunohistochemical analysis of 65 specimens of ocular neoplasias and 30 normal controls diagnosed between 1991 and 2002 at a tertiary eye care hospital, was undertaken. Formalin-fixed, paraffin-embedded tissues were reviewed for confirming histopathological diagnosis, presence of koilocytosis and changes related to actinic keratosis. Immunohistochemical analysis was done using HPV-specific monoclonal antibodies. Clinicopathological correlation and the association of HPV antigen with the histopathological features were performed. RESULTS: Out of the 65 cases analyzed, 35 were papillomas and 30 were ocular surface squamous neoplasias (OSSN). The mean age was 48 years with a male preponderance. Histologically, koilocytosis was observed in 17.1% of papillomas and 36.6% of OSSN. Actinic keratosis was present in 33% of OSSN. Immunohistochemically 17.1% conjunctival papillomas stained positive for HPV antigen, all cases of OSSN were negative for HPV. There was no correlation between koilocytosis or actinic keratosis and the detection of HPV antigen. CONCLUSIONS: The association between HPV and conjunctival neoplasias is variable in different geographical areas and also depends on the methods of detection used. This study warrants the need for applying more advanced techniques at a molecular level to determine the possible etiology of HPV in conjunctival neoplasias among Asian-Indians.