Development and Validation of a Predictive Score for Preoperative Diagnosis of Early Stage Epithelial Ovarian Cancer

Objective: To develop and validate a simplified multi-parameter risk-based scoring system for preoperative diagnosisof early stage epithelial ovarian cancer. Methods: All women presented with adnexal mass and were scheduled foroperation at Phrapokklao hospital during September 2013 – December 2017 were included and categorized accordingto their histopathologic reports into early stage ovarian cancer groups and benign ovarian tumor groups. Multivariablelogistic regression was used to explore for potential predictors. The selected logistic coefficients were transformedinto risk-based scoring system. Internal validation was done with bootstrapping procedure. Results: A total of 270participants were included in analysis and predictive model development, 54 in early stage ovarian cancer group and216 in benign ovarian tumor group. Menopausal status, two abnormal ultrasound findings (presence of solid componentor ascites), tumor size and serum CA-125 level were used for derivation of the scoring system. The score-based modelshowed area under ROC of 0.88 (95%CI 0.82-0.93). The developed scoring system ranged from 0 to 51 was classifiedinto 3 subcategories for clinical practicability. The positive predictive values for the presence of early stage ovariancancer were 2.07 (95%CI 0.43-6.05) for low risk patient, 29.13(95%CI 19.65-41.58) for moderate risk patient, and95.45(95%CI 77.16-99.88) for high risk patient. Conclusion: This simplified risk-based scoring system for preoperativediagnosis of early stage ovarian cancer could aid general physicians or general gynecologists in evaluation of patientspresenting with ovarian tumors and help gynecologic oncologists in management planning and prioritization of patientsfor operation.