INTRAOPERATIVE FROZEN SECTION ANALYSIS OF ENDOMETRIOID OVARIAN BORDERLINE TUMOR: A DIFFICULT DIAGNOSIS

Abstract

Abstract Introduction/Objective Borderline ovarian tumors (BOT) comprise approximately 15% of all primary ovarian neoplasms; of these endometroid borderline ovarian tumors (EBOT) are much rarer (2-3%). BOT is often potentially misdiagnosed as a malignant tumor based on its challenging histomorphological features and thus, treated aggressively. Herein, we present an unusual case of EBOT with adenofibromatous pattern in a 50-year-old gravida 3, para 2 female diagnosed on intraoperative frozen sections (IOFS). Methods/Case Report Patient with history of endometriosis presented with left lower quadrant abdominal pain. MRI revealed complex bilateral ovarian masses with solid and cystic components measuring 5 cm and 6.7 cm in right and left ovary, respectively. An ovarian malignancy was suspected. Patient underwent exploratory laparotomy, total abdominal hysterectomy with bilateral salpingo-opherectomy, and omentectomy. Grossly, bilateral ovaries (BO) showed intact capsule with solid and cystic components. On IOFS, the solid areas demonstrated endometrioid glands arranged in a lobular fashion with squamous morules. The cystic component demonstrated papillary projections with squamous differentiation. Cytology is mildly atypical at best. Based on these findings, a diagnosis of EBOT was made, necessitating staging. Differential diagnoses include atypical endometriosis, endometrioid adenofibroma (EAF) and endometrioid adenocarcinoma (EA). Lack of endometrial stroma surrounding the glands ruled out endometriosis. Presence of CC with papillary architecture ruled out EAF and lack of destructive stromal invasion with desmoplasia, confluence of glands and significant cytologic atypia ruled out EA. Final histopathological diagnosis of formalin-fixed paraffin-embedded specimen revealed EBOT, pT1bN0M0. Uterus and cervix revealed endometrial hyperplasia with atypia, adenomyosis, leiomyomas, and endocervical polyp. Results (if a Case Study enter NA) NA Conclusion The accurate diagnosis of BOT during IOFS is critical as it directs surgeons towards staging studies and in choosing conservative surgical treatment over aggressive treatment especially in cases of young women who desire future childbearing. As this is a rare entity, it serves the pathologist well to keep all relevant differential diagnoses in mind.