DNA Content as Prognostic Factor in Cervix Carcinoma Stage IB-III Treated with Radiotherapy

Abstract

A prognostic value of DNA content in cervix carcinoma for local recurrence following radiotherapy is suggested by both retro- and prospective studies. The purpose of this study was to confirm these data. Flow cytometry and computerized image cytometry were used to measure DNA content of tumor cells retrospectively in paraffin-embedded archive material from 98 patients with carcinoma of the uterine cervix FIGO stage IB-III. All patients were treated with combined megavoltage irradiation and brachytherapy. Minimum follow-up has been 5.1 years. Pelvic recurrence was seen in 10, 26, and 54% of patients with stages IB, II, and III, respectively ( P = 0.003). DNA content, expressed as DNA index (DI), was not correlated with the FIGO stage ( P = 0.25), histopathologic grading ( P = 0.26), or age ( P = 0.63) at diagnosis in this series. Using univariate analysis, pelvic disease-free survival (PDFS) was best predicted by the clinical stage ( P = 0.004) and by an age greater than 55 years ( P = 0.04) before treatment. PDFS tended to be better for patients with aneuploid tumors (DI > 1.2), but this difference was not statistically significant ( P = 0.17). Using Cox's regression model for multivariate analysis, only stage was independently correlated to PDFS ( P = 0.009). After stratification for stage, ploidy level was significantly correlated with PDFS in stage II patients ( P = 0.04). Overall results suggest aneuploid tumors to be more radiosensitive than diploid tumors in this series.