Proliferative capacity in head and neck cancer

Background. Shortening of overall treatment time (accelerated radiotherapy) appears to result in an increase of the efficacy of irradiation. In this s tudy, we compared the proliferative capacity between tumors originating in different sites of the head and neck region. Tumors with a large proliferat ing capacity might, theoretically, benefit most from accelerated radiothera py. Material and Methods. BrdUrd was administered intravenously in patients wit h head and neck carcinomas. Tumor samples were analyzed with flow cytometry . T and N stages were assessed in accordance with the TNM classification sy stem (UICC 1987). Results. No significant differences in proliferation parameters were observ ed with respect to site of origin of head and neck tumors. For T3/T4 tumors , DNA ploidy is an important tumor characteristic: G1- and S-phase fraction s, labeling index, and tumor doubling time Tpot differences were statistica lly significant; the aneuploid tumors showed the largest proliferative pote ntial. Conclusions. (1) In general, no significant differences in proliferation pa rameters were observed with respect to site of origin. (2) Aneuploid head a nd neck tumors have a higher proliferative capacity than diploid ones, they might benefit most from accelerated irradiation. (C) 2001 John Wiley & Son s, Inc.