Role of Frozen Sections in Diagnosing Female Genital Tract Lesions: A Tertiary Centre Study in Chennai, India

Abstract

Introduction: Female Genital Tract (FGT) malignancies are common with ovarian cancers having high incidence and mortality. The asymptomatic character, difficult location and lack of effective screening methods make Intraoperative Frozen Section (IFS) an effective diagnostic test to guide the surgical decisions. Aim: To assess the performance of IFS, describe the associated demographic, clinicopathological factors and identify the errors leading to discordance when compared with Permanent Section (PS). Materials and Methods: A retrospective study of all the consecutive IFS consultations related to FGT lesions received in the Pathology Department between January 2013 to June 2022 was conducted between July 2022 to September 2022 at ESIC Medical College and Hospital, Chennai, Tamil Nadu, India. Cases with IFS deferred until PS section were excluded. The FS and PS reports, demographic, clinicopathological data, Risk of Malignancy Index (RMI), imaging and biochemical records were retrieved. In-depth descriptive analysis of clinicopathological parameters as frequency and percentage, frequency distribution of PS diagnosis, concordant and discordant categorisation, reasons for the discordance were described and the diagnostic accuracy of Frozen Section (FS) tool was calculated. Mean, Frequency (n) and percentage (%) analysis was done for the complete collected data. Results: Out of the total 35 FGT related IFS consultations received, 32 (91.43%) was for Ovarian Tumours (OT), which included 26 surface epithelial tumours, three sex cord stromal tumours, two germ cell tumours, one Krukenberg tumour. Two cases were deferred due to extensive haemorrhage and infarction. Confirmation of the diagnosis was the most common indication. The mean size of the OT (n=32) was 13 cm and ranged from 2 to 31 cm. RMI was low (<25) in 14 (44%, n=32), intermediate (25-250) in 10 (31%, n=32) and high (>250) in 8 (25%, n=32) of OT. The diagnostic accuracy of FS of all the FGT cases (n=35) was 85.71% (n=35 FGT cases) with an error rate of 14.29% was observed. Five OT cases had discordant FS diagnosis, 3 cases due to sampling error and mis-interpretation error in the remaining 2 cases. Artefacts like poor morphology due to tissue freezing, nucleomegaly, poor sectioning and section folding were observed in the discordant cases. Conclusions: Correct use of IFS along with careful preoperative work-up will help the surgeon intraoperatively. A good rapport among clinicians, pathologists and laboratory personnel will aid to improve the diagnostic accuracy. Periodic assessment of IFS tool is necessary as a quality check.