Naritaka Mizutani

Effects of preoperative radiation and chemotherapy on AgNOR counts in oral squamous cell carcinoma

PURPOSE This study evaluated the relationship between argyophilic nucleolar organizer regions (AgNORs) and the histologic effects of preoperative chemotherapy or external radiation on oral squamous cell carcinoma. PATIENTS AND METHODS Thirty-three cases of oral squamous cell carcinoma that were treated with chemotherapy (pepleomycin or 5-FU) or 60Co external radiation were studied. Biopsies were done on the tumor sites before therapy and the number of AgNORs per nucleus was recorded. After therapy, the tumors were resected and the therapeutic effects were assessed histologically. RESULTS The number of AgNORs per nucleus before therapy ranged from 4.7 to 12.45 (mean +/- SD, 8.71 +/- 2.26). As the number of AgNORs per nucleus increased, the histological effects of preoperative therapy were enhanced. It was 5.75 +/- 0.77 in cases with a poor histological effect of preoperative treatment, 8.03 +/- 1.85 in cases with a mild histological effect, 9.09 +/- 1.85 in the moderate histological effect group, and 10.46 +/- 1.56 in the excellent histological effect group. CONCLUSION These results suggest that AgNORs could be used to predict the effects of preoperative radiation and chemotherapy on oral squamous cell carcinoma.

Cell kinetic analysis of oral squamous cell carcinoma by using nuclear DNA-RNA contents and antibody to bromodeoxyuridine.

Concerning cell kinetics of oral cancer, the following findings were obtained as a result of both measurement of nuclear DNA-RNA contents, and examination using antiBromodeoxyuridine (BrdU) monoclonal antibody.1. A significant difference was noted between the BrdU labelling index of normal gingival epithelium (2.9±0.5%) and that of oral squamous cell carcinoma (11.4±3.8%) . In the normal epithelium positive identification was restricted to the basal cell layer or the 2nd-3rd supra basal cell layers ; while in squamous cell carcinoma, it was commonly observed to occur around the focus of tumor cells in the well differentiated area, and was seen scattered in the poorly differentiated area.2. No definite relationship was observed between the BrdU labelling index and clinical stages of tumor. With respect to the relationship with histopathological malignancy, the labelling index did not show any association with the grading of differentiation or atypia, but showed positive correlation with the mitotic index. The value of the labelling index was 11.5 times as large as that of mitotic index.3. With the introduction of the BrdU labelling index applied to the results of measurement of nuclear DNA-RNA contents was it admittedly possible to clarify its significance in oral squamous cell carcinoma, a factor which had not been revealed by conventional analyses.