Preoperative nomogram for prediction of microscopic parametrial infiltration in patients with FIGO stage IB cervical cancer treated with radical hysterectomy

Objective. This study aimed to establish a nomogram to predict microscopic parametrial infiltration (PMI) by combining preoperative clinicopathologic factors in FIGO stage IB cervical cancer patients treated by radical hysterectomy (RH). Methods. We retrospectively analyzed clinicopathologic data of 298 patients with FIGO stage IB cervical cancer treated by RH between February 2000 and March 2015. The nomogram was developed based on multivariate logistic regression analysis of preoperative clinicopathologic data. The accuracy and discriminative ability of the nomogram were evaluated by a concordance index and calibration curve. The low-risk group was predefined as having a predicted probability of PMI <10%. Results. Multivariate analysis identified diameter-based tumor volume and disruption of the cervical stromal ring on magnetic resonance imaging, serum squamous cell carcinoma antigen level, and menopausal status as independent prognostic factors associated with PMI. The concordance index of the nomogram was 0.940 (95% CI, 0.908-0.967), and calibration plots revealed good agreement between the observed probabilities and nomogram-predicted probabilities (Hosmer Lemeshow test, p = 0.574). The nomogram classified 200 out of 298 patients (67.1%) as low risk. In the low-risk group, the predicted probability of PMI was 3.5% and the actual PMI rate was 2.5% (5 out of 200). Conclusions. We developed a preoperative nomogram predicting microscopic PMI in surgically treated FIGO stage IB cervical cancer patients. The probabilities derived from this nomogram may have the potential to provide valuable guidance for physicians regarding the primary management of FIGO stage IB cervical cancer patients. (C) 2016 Elsevier Inc. All rights reserved.