A novel risk-scoring model for prediction of premalignant and malignant lesions of uterine endometrium among symptomatic premenopausal women

Purpose: Uterine cancer is the second most prevalent cancer of the female genital tract, with 90% of it being of endometrial origin. The aim of this research was to create and validate a risk-scoring model using patients’ clinical variables in predicting premalignant and malignant lesions of the uterine endometrium among premenopausal women with abnormal uterine bleeding (AUB). Methods: This is a retrospective cohort study conducted at a tertiary hospital of Southern India for a period of 5 years from July 2014 to August 2019, including women aged ≤55 years who had AUB and underwent endometrial biopsy. The incidence of atypical endometrial hyperplasia (AEH) and endometrial cancer (EC) was determined, and clinical and demographic variables were compared among cases (AEH/EC) and controls (no AEH/EC) using simple logistic regression. A risk-scoring model was derived and validated with a split-sample internal validation method. Results: A total of 472 premenopausal women presenting with AUB were included in the study. There were 20 women (4.2%) with AEH and eight (1.7%) with EC. We found a statistically significant positive correlation of an anovulatory pattern of bleeding (odds ratio [OR]=3.4; p=0.009), age ≥45 years (OR=1.12; p=0.01), body mass index (BMI) ≥30 kg/m2 (OR=2.46; p=0.04) and diabetes mellitus (OR=3.00; p=0.02) with a higher risk of AEH/EC diagnosis upon histopathological examination of endometrial biopsy specimens of the study population. A risk-scoring model (PAD30) was created using these variables to predict premalignant and malignant endometrial lesions. The best cutoff score derived by the receiver operating characteristics (ROC) curve, of ≥5, had a sensitivity of 85.7% and specificity of 87.6% with an area under the curve (AUC) of 0.84 (95% CI 0.75–0.93; p=0.04). With a positive likelihood ratio of 6.91, our prediction model increases the post-test probability of AEH/EC to 30.6% from 6% of the pre-test probability. Conclusion: The proposed model demonstrated a moderate diagnostic accuracy in predicting premalignant and malignant lesions of the uterine endometrium among symptomatic premenopausal women.