COMPARISON OF IN-VIVO AND IN-VITRO PROSTAGLANDIN E(2) PRODUCTION BY SQUAMOUS-CELL CARCINOMA OF THE HEAD AND NECK

Prostaglandin E(2) has been identified as an immunosuppressive factor in patients with squamous cell carcinoma of the head and neck. Spontan eous prostaglandin E(2) production by 21 cancer cell lines, which were obtained from 17 patients with squamous cell carcinoma of the head an d neck, was determined by radioimmunoassay. In comparison with normal keratinocyte cultures, prostaglandin E(2) production by cancer cell li nes was significantly decreased (P < 0.0001). Prostaglandin E(2) level s demonstrated no correlation to the site, stage, or histopathologic d ifferentiation of the tumor. In a separate group of 17 patients with s quamous cell carcinoma of the head and neck, tumor cells were isolated from fresh tumor specimens, and 24-hour PGE(2) production in vitro wa s assayed. No correlation was found with tumor site, stage, or 5-year disease-free survival. Although prostaglandin E(2) may have biologic s ignificance in vivo in patients with squamous cell carcinoma of the he ad and neck, these findings suggest that measurements of tumor cell-de rived prostaglandin E(2) are not predictive of biologic behavior.