A low-grade mucinous neoplasm arising within an ovarian mature cystic teratoma: a case report

A 52-year old female presenting with an ovarian mass underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy. Intra-operatively there was large volume ascites containing mucin and hair. Subsequent pathological examination of the ovarian mass revealed a low-grade mucinous neoplasm arising within a mature cystic teratoma (MCT). This was associated with pseudomyxoma peritonei (PMP) and is a rare entity recognized by the World Health Organisation. These tumours resemble their appendiceal counterpart and therefore diagnosis is achieved with immunohistochemistry and thorough morphological assessment to exclude a collision tumour. Additionally, the appendix should be examined to confirm ovarian origin. Identification of these neoplasms is crucial as reasonable outcomes can be achieved following appropriate referral for ongoing management which includes complete surgical cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC).