Radiosensitivity in squamous cell carcinoma of head and neck

Squamous cell carcinoma of the head and neck in 31 previously untreated patients was histologically classified as Grades I-III according to the modified WHO grading for differentiated, proliferative, and atypical findings. Correlation between histologic grades and the response to radiotherapy (radiosensitivity) was examined. There was a significant correlation between overall grades for three items and radiosensitivity (p<0.02). Degrees of proliferation and differentiation were strongly correlated with radiosensitivity (p<0.02, p<0.03). Not only the differentiated degree but also the proliferative degree should be used in the evaluation of radiosensitivity of carcinoma. The introduction of the WHO grading would make it possible to evaluate the radiosensitivity more easily at the optical level. (Namekawa, K)