Assessment of gross examination and frozen section of uterine specimen in endometrial cancer patients

The accuracy of intra-operative gross visual examination of myometrial invasion of uterine specimen has been evaluated in several studies with controversial results. The intra-operative frozen section (IFS) analysis is used to identify patients at high risk for pelvic and para-aortic nodal metastasis in order to avoid lymphadenectomy in low-risk patients. However, there is still some controversy concerning the efficiency of IFS. The aim of this study was to evaluate the accuracy and validity of frozen section diagnosis and gross examination of uterine specimen compared to the final histological results in patients with endometrial cancer. The study group comprised 31 patients with a pre-operative histopathological diagnosis of endometrial carcinoma. Comprehensive surgical staging was performed in all patients. Intra-operative gross examination of the uterine cavity and wall with frozen section analysis was performed. Lymphadenectomy was performed in all patients. After frozen section analysis, the uterus together with removed lymph nodes was stored and subjected to final pathologic diagnoses. Gross examination accurately identified microscopic invasion of myometrium in 86.6% of the patients with 88.9% sensitivity, 85.7% specificity and negative and positive predictive values of 72.7 and 94.7%, respectively. The kappa was 0.70 (p < 0.0001) with a 95% CI 0.432-0.968. Frozen section in 90% of cases was correctly reporting final histopathological myometrial invasion with sensitivity 88.9%, specificity 90%, positive and negative predictive values 80 and 94.7%, respectively. The kappa was 0.76 (p < 0.0001) with a 95% CI 0.51-1.009. These data confirm the previous reports for the accuracy of gross examination and frozen section diagnosis in early stage and low-grade tumors.