Objective: The enzyme cyclooxygenase catalyzes the first step of the synthesis of prostanoids Cyclooxygenase has been shown to exist in two distinct isoforms: cyclooxygenase-1 is constitutively expressed as a housekeeping enzyme in most tissues whereas the inducible cyclooxygenase-2 has been reported to be involved in inflammatory processes and in the carcinogenesis of squamous cell carcinoma. The aim of this study was to investigate the distribution patterns of cyclooxygenase-1 and -2 in peritumoral lymphocytic infiltrates and tumor cells of head and neck carcinoma.
Material and methods: Immunohistochemical analysis was performed using paraffin-embedded tumor specimens from 24 patients suffering from oropharyngeal, hypopharyngeal and oral squamous cell carcinomas.
Results: We observed that cyclooxygenase-2 immunoreactivity, compared to that of cyclooxygenase-1, was significantly increased in peritumoral lymphocytic infiltrates as well as in tumor cells.
Conclusion: The expression of cyclooxygenase-2 in both tumor specimens and the surrounding peritumoral lymphocytic infiltrates supports the hypothesis that cyclooxygenase may be one of several important links between chronic inflammation and carcinogenesis.