INCREASED MUTAGEN SENSITIVITY IN HEAD-AND-NECK SQUAMOUS-CELL CARCINOMA PATIENTS, PARTICULARLY THOSE WITH MULTIPLE PRIMARY TUMORS

Mutagen sensitivity is a constitutional factor which may be used to id entify head-and-neck squamous-cell carcinoma (HNSCC) patients at high risk for the development of multiple primary tumors (MPT). In this ret rospective study, mutagen sensitivity was measured in HNSCC patients w ith a single primary tumor (SPT), HNSCC patients who have already deve loped MPT and control subjects with no tumor history. In vitro, lympho cytes were challenged with bleomycin and chromosomal damage was quanti fied by scoring chromatid breaks of 100 cells. A significant differenc e in the mean number of breaks per cell (b/c) was found between SPT pa tients and controls. Patients with MPT showed a significantly higher m ean b/c value than SPT patients. This increase in mutagen sensitivity in HNSCC patients was not related to well-known cancer risk factors su ch as age, or life-style factors such as smoking and alcohol drinking habits. In addition, tumor site but not tumor stage was found to be re lated to mutagen sensitivity. On the basis of our findings, we propose that mutagen sensitivity is not an independent risk factor but a cons titutional factor which reflects the way in which genotoxic compounds are dealt with and is thereby directly related to cancer risk. (C) 199 4 Wiley-Liss, Inc.