Tumour cell kinetics as a prognostic factor in squamous cell carcinoma of the cervix treated with radiotherapy

Purpose: Proliferative rate and DNA ploidy status were evaluated by flow cy tometry in cervical cancer patients, prior to radiotherapy, to assess their importance as prognostic factors to predict survival rates. Material and methods: Between 1987 and 1995, a total of 260 patients with s quamous cell carcinoma (SCC) of the cervix, FIGO stages IB-IIIB were analys ed. Tumour samples were incubated with bromodeoxyuridine (BrdUrd) in vitro to measure their total labelling index (totLI) and LI (totLI for diploid an d anLI for aneuploid tumours). Proliferation was also assessed by S-phase f raction (SPF) analysis of the DNA profile. Patients had intracavitary thera py (three applications, each of 16 Gy to point A) and XRT of 40-50 Gy given over 4-5 weeks. Results: The cervical tumours were characterized by a high proliferation ra te which varied within each clinical stage of disease. The totLI ranged fro m 1.1 to 33.1% with median value of 9.6% whilst the LI ranged from 1.1 to 3 7.1% with a median value of 10.9%. Univariate analysis identified patient's age (cut-offpoint less than or equal to 50&greater; years) and to a lesser extent proliferation (cut-off point, median totLI = 9.6%) as significant p rognostic factors for 5-year survival. The median survival time for younger patients ( less than or equal to 50 years) with tumours of low proliferati on (totLI less than or equal to 9.6%) tumours was 17.5 months compared with 56 months in the faster proliferating tumours (P = 0.0354). In the older p atient sub-group, proliferation rate had no influence on survival. The medi an LI value was not a useful parameter in survival. Cox multivariate analys is showed that patient age ( less than or equal to 50 years) and low prolif eration of the tumour cells (totLI less than or equal to 9.6) were unfavour able prognostic factors for cervical cancers treated with radiotherapy. DNA ploidy was not significant in this series. Conclusions: These data suggest that further improvements in therapy might be gained by selection of alternative treatments strategies such as neoadju vant chemotherapy or radiation sensitizers in younger patients with more sl owly proliferating tumours. (C) 1999 Elsevier Science Ireland Ltd. All righ ts reserved.