Inverse correlation between serum PGE2 and T classification in head and neck cancer

Background. Prostaglandin E2 (PGE2) serum levels have been shown previously to be increased in tumor bearing mice as well as in patients with solid tumors; however, the impact on the course or stage of disease has not been shown. We hypothesized that PGE2 is strictly required for aggressive and especially early-stage tumors of the head and neck to provoke invasion and angiogenesis. Methods. We analyzed the serum PGE2 levels of 100 patients with head and neck squamous cell carcinoma of different stages before and 1 year after treatment and compared the results with the serum levels of 40 healthy donors and the secretion profile of 8 different squamous cell carcinoma cell lines. Results. Our investigations showed a statistically significant inverse correlation between PGE2 serum levels and tumor stage. Furthermore, this effect has been reflected by the results of our cell culture analyses, which showed an inversely regulated PGE2 secretion into the medium during the process of proliferation. Interestingly, the serum levels of PGE2 were significantly downregulated 1 year after successful treatment. Conclusions. We conclude that PGE2 serum level as an indicator for early-stage cancer of the head and neck may function as a tumor marker during the follow-up period. (c) 2006 Wiley Periodicals, Inc.