Study on nucleolar organizer regions (NORs) in squamous cell carcinomas of the uterine cervix treated with chemoradiotherapy

Abstract

Purpose: This study is to asses the meaning of the number of NORs in tumor cells nuclei compared with other proliferative markers before and during chemoradiotherapy.
Material and Method: Forty six biopsy specimens from twenty three patient with cervical squamous cell carcinoma treated with chemoradiotherapy taken before radiotherapy and at 10 Gy were analyzed. The number of NORs was measured using the silver stained method. The MIB-1 LI and p53 labeling indexes (LI) were measured by using immunohistochemical method.
Result: After 10 Gy irradiation, the number of NORs (AgNOR score) was decreased from 4.93 to 3.39 (p<0.0001). MIB-1-LI and MI were increase from 25.55 to 39.05 (p<0.0001) and from 0.0059 to 0.0122 (p<0.0001), respectively. Before radiation therapy, we found positive correlation between AgNOR score and MIB-1-LI (p=0.0002), and MI (p=0.0017). At 10 Gy, there was no significant correlation among number of NORs, MIB-1-LI, MI and p53-LI.
Conclusion: The number of NORs can be used as proliferative marker for assessing tumor cell proliferative activity before chemoradiotherapy, but not during therapy.