Comparison of transvaginal ultrasonography (TVS), magnetic resonance imaging (MRİ) methods with pathological examination of frozen section in determining depth of myometrial invasion in patients diagnosed with endometrial cancer

Objective: The aim of this study was to investigate the efficacy levels of transvaginal ultrasonography (TVS) and magnetic resonance imaging (MRI) methods in determining the depth of myometrial invasion by comparing the results of the methods performed preoperatively with the final results of frozen section examination performed by pathologists intraoperatively. Materials and Methods: In this prospective study, preoperative TVS, MRI and intraoperative frozen section examinations were performed on 65 patients diagnosed with endometrial cancer using the diagnostic probe curettage in the Inonu University, Turgut Ozal Medical Center, Obstetrics and Gynecology Clinic between February 2017 and August 2018 to determine the depth of myometrial invasion. All three methods were evaluated by the same gynecologist, radiologist and pathologist. The results were compared with the final pathology result as the gold standard. The data were analyzed using SPSS 22.0 statistical package software. Results: Our study included 65 patients. The patients' ages were between 38 and 89 and the mean age was 60.75±12.28 years. It was found that frozen, TVS and MRI had a sensitivity of 100/88.64/63.64%, a specificity of 85.71/90.48/95.24%, a PPV (positive predictive value) of 93.62/95.12/96.55%, a NPV (negative predictive value) of 100/79.17/55.56% and an accuracy of 95.38/89.23/73.85%, respectively. At the same time, factors such as grade, tumor size, LVSI, P53, Ki-67 were also found to be effective on the depth of myometrial invasion. Discussion: We compared frozen, TVS and MRI methods to determine the depth of myometrial invasion in patients with endometrial cancer. Among three methods, the frozen results were determined to be the closest to the final pathology results. Frozen section examination is an easy and reliable method. Intraoperative lymphadenectomy decision can be made by taking the result of frozen section examination into consideration. We found that our TVS results were similar or higher than the results of previous studies. However, it was exact opposite for MRI. The results of MRI were found to be lower than the other two methods in the literature and our study. The accuracy rates were found as follows: frozen was higher than TVS and TVS was higher than MRI. Keywords: Endometrial cancer, depth of myometrial invasion, magnetic resonance imaging, transvaginal ultrasonography, frozen, final pathology