Purpose: This study was undertaken to evaluate the efficacy of postoperative radiotherapy (post-OP RT) and to investigate the prognostic factors for early-stage cervical cancer patients who were treated by radical surgery, and the pathological findings suggested a relatively high risk of relapse with surgery alone.
Materials and methods: From January 1990 to December 1995, 222 patients with stage IB-IIA cervical cancer, treated by radical surgery and a full course of post-OP RT, were included in this study. The indications for post-OP RT were based on pathological findings, including lymph node metastasis, positive surgical margins, parametrial extension, lymphovascular permeation, and invasion of more than two-thirds of the cervical wall thickness. The radiation dose of external beam was 44-45 Gy to the whole pelvis and 50-54 Gy to the true pelvis. One hundred seventy-two patients also received intravaginal brachytherapy as a local boost. The minimal follow-up period was 2 years.
Results: The actuarial 5-year overall and disease-specific survival rates for all patients were 76 and 82%, respectively. The tumor control rate within the pelvis reached 94%, and distant metastasis was the major cause of treatment failure. Univariate analysis of clinical and pathological parameters revealed that clinical stage, bulky tumor size, positive lymph nodes, parametrial extension, and histologic type were significant prognostic factors. After multivariate analysis, only positive lymph nodes (P = 0.01), bulky tumor size (P = 0.02), and parametrial extension (P = 0.05) independently influenced the disease-specific survival (DSS). For patients with lymph node metastasis, the number and location of the nodal involvement significantly affected the prognosis. The 5-year DSS for patients with no, one, and more than one lymph node metastasis were 87, 84, and 61% (P = 0.0001), respectively. Patients with upper pelvic lymph node metastasis had a higher incidence of distant metastasis (50% vs 16% in lower pelvic node group, P = 0.03). In the subgroup of single lower pelvic nodal metastasis, the prognosis was similar to that of patients without lymph node involvement (5-year DSS 85% vs 87%, P = 0.71).
Conclusion: Our results indicate that post-OP RT can achieve very good local control in stage IB-IIA cervical cancer patients whose pathological findings show risk features for relapse after radical surgery. The prognostic factors for treatment failure identified in this study can be used as selection criteria for clinical trials to test the effects of other adjuvant treatments, such as chemotherapy. Patients with a single lower pelvic lymph node metastasis have a relatively good prognosis and may not need adjuvant treatment beyond radiation therapy.
Copyright 1999 Academic Press.