Epidermoid or dermoid cysts of the ovary? Clinicopathological characteristics of 28 cases and a new pathologic classification of an old entity

Objective: The aim of this study was to present the clinical and pathological findings that aid in the differential diagnosis between epidermoid and dermoid ovarian tumors. Materials and methods: This was a 15-year retrospective clinico-pathological study. A total of 28 cases of epidermoid ovarian cysts histologically confirmed after pathological examination at the Pathology Laboratory of Aretaieion University Hospital between January 1996 and December 2010, were analyzed and a literature review was performed. Results: Patients with epidermoid cysts presented with a main complaint of either abdominal pain or a palpable abdominal mass. In the 28 cases studied, 18 patients underwent cystectomy and four cases underwent oophorectomy. In six cases of post-menopausal women, abdominal hysterectomy with bilateral salpingo-oophorectomy was performed. No recurrent disease in the pelvis was reported during the available follow-up period which was from 12 to 30 months. Discussion: Epithelial epidermoid ovarian tumors represent less than one percent of ovarian surface epithelial tumors. The differential diagnosis of epidermoid cysts includes dermoid (mature cystic teratomas) tumors of the ovary. However, it should be mentioned that up to 17% of teratomas may include epidermoid tumors. In comparison to dermoid cysts which present at an earlier age but with a greater size, ovarian epidermoid tumors present as small- to medium-sized cystic lesions occurring at a significantly older age. The treatment of choice is conservative surgical therapy.

Ovarian tumors; Mature cystic teratomas, Dermoid cysts

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