A study on the influence of preoperative radiotherapy to proliferating cell nuclear antigen (PCNA) for oral cancer cells

In order to evalute the effects of preoperative irradiation therapy on oral cancer, monoclonal antibody to proliferating cell nuclear antigen (PCNA) was used to calculate PCNA positive rates before and after 30Gy irradiation therapy. The subjects were 24 patientas with oral cancer. Based on the results, the relation between PCNA positive rate and the histolosical effects of irradiation therapy was quantitatively analyzed. The conclusions are summarized as follows.

1)	The average pretreatment PCNA positive rate was 33.4±11.4% while the average posttreatment rate was 24.0±7.9%.
2)	Subjects were classified according to the degree of differentiation for pretreatment and posttreatment comparison. However, there existed no significant difference in PCNA positive rate.
3)	Subjects were classified according to stage of oral cancer for pretreatment and posttreatment comparsion, however there existed no significant difference in PCNA positive rate.
4)	When the decrease in PCNA rate was compared between the group showing negative irradiation effects and that showing positive effects, the fact that the latter group showed remarkably greater decrease in PCNA rate, indicated a significant difference between the two groups.
5)	Pretreatment PCNA positive rate was higher in the group showing positive irradiation effects than in that showing negative effects and the difference was significant between the two groups. Beneficial effects of irradiation therapy could be expected in those who showed pretreatment PCNA positive rates of more than 30.0%.
6)	The accuracy rate for giagnosis based on PCNA positive rate, and macroscopic and histologic judgment was 58.3%.