Alteration of Ki‐67, DNA content and cell cycle distribution during radiotherapy for cervix cancer

Abstract

SUMMARY In a prospective study involving 158 patients with carcinoma of the uterine cervix, DNA content, S-phase fraction (SPF), and Ki-67 proliferative index were evaluated in fresh tissue using flow cytometry and immunocytochemical analysis. Of all tumors, 57.1 % were aneuploid. In this subgroup, 25% of tumors had a DNA index between 1.6 and 1.8. SPF values ranged from 0.5 to 57.2% and were significantly higher (P < 0.0001) in tumors with an abnormal DNA content (aneuploid). Ki-67 labeling index ranged from 1.7 to 65.0%. No association was found between any of the above-mentioned parameters and clinical stage or histological type of tumor. When analyzing overall survival, a statistically significant difference was found between stage IIB patients with aneuploid and diploid DNA content. In 39 carcinomas evaluated after 1 week of radiotherapy, irradiation induced a significant decrease in Ki-67 index. In 7 aneuploid tumors where cell cycle analysis was feasible, a significant increase in G2 + M phase fraction was observed (P < 0.02). We suggest these parameters are therefore useful to monitor radiation-induced alterations in cell cycle and proliferation. Rudiut Oncol Invest 1995;3:34-41. o 1995 Wiley-Liss, hc.