Flow-cytometric DNA analysis of early stage adenocarcinoma of the cervix

Objective. The purpose of this study was to determine the utility of DNA flow cytometry as a prognostic indicator for risk of recurrence and overall survival in patients with early stage adenocarcinomas of the uterine cervix. Methods. DNA flow cytometry was performed to determine ploidy, DNA index, and proliferative index in 66 women with stages IB and IIA pure mucinous adenocarcinomas of the cervix treated by primary surgical therapy with radical hysterectomy and pelvic lymphadenectomy. Fifty-seven of 66 (86.3%) tissue samples were analyzable. Three sections were obtained from paraffin- embedded tissue blocks containing primary tumor. Flow-cytometric results, along with other known prognostic variables for risk for recurrent disease and survival, were analyzed using Cox regression proportional hazards model, and survival curves were generated by the Kaplan-Meier method. Results. Of 57 interpretable samples, DNA ploidy patterns were 18 (27%) diploid, 8 (12%) tetraploid, and 31 (47%) aneuploid. Thirteen of 66 patients (20%) experienced recurrence with a median time to recurrence of 1.6 years. No significant correlation was noted between DNA ploidy and risk of recurrence (P = 0.429). Multivariate analysis confirmed that positive metastatic lymph nodes were associated with risk of recurrence (P < 0.001). In node-negative patients, a high proliferative index (S% + G₂M% > 20%), measured as a continuous variable, was the only significant factor for tumor recurrence (P = 0.002). Conclusion. DNA ploidy does not predict a patient's risk for tumor recurrence; however, a high proliferative index value warrants further investigation as a potential prognostic indicator for risk of recurrent disease in patients with adenocarcinoma of the uterine cervix.