A model for prediction of parametrial involvement and feasibility of less radical resection of parametrium in patients with FIGO stage IB1 cervical cancer

ObjectiveThe objective of this study was to evaluate the potential risk factors associated with parametrial invasion and to identify preoperatively a subgroup of patients at low risk for parametrial involvement who could be appropriate candidates for less radical surgery in FIGO stage IB1 cervical cancer.MethodsWe retrospectively reviewed the medical records of 317 FIGO stage IB1 cervical cancer patients undergoing class III radical hysterectomy and bilateral pelvic lymphadenectomy. Clinocopathologic factors associated with parametrial invasion were analyzed and the risk criteria predicting parametrial involvement were calculated using a logistic regression model.ResultsOf 317 patients, 17 patients (5.4%) had parametrial involvement. Tumor size > 3 cm (OR, 3.80; [95% CI, 1.19–12.06]; p = 0.02) and pelvic lymph node metastasis (OR, 3.02; [95% CI, 1.04–8.79]; p = 0.04) were independent pathologic factors for parametrial invasion on multivariate analysis. Significant preoperative factors associated with parametrial involvement were tumor size > 3 cm (OR, 4.29; [95% CI, 1.43–12.89]; p < 0.01) and serum SCC Ag level > 1.40 ng/mL (OR, 3.27; [95% CI, 1.11–9.69]; p = 0.03). We identified 185 low-risk (tumor size ≤ 3 cm and SCC ≤ 1.4 ng/mL) and 132 high-risk (tumor size > 3 cm and/or SCC > 1.4 ng/mL) patients. The rates of parametrial involvement in low- and high-risk patients were 1.1% and 11.4%, respectively (p < 0.01).ConclusionsIn this dataset, a model using tumor size and SCC Ag level is highly predictive of parametrial involvement in patients with stage IB1 cervical cancer and may identify candidates for less radical parametrial resection.