Primary Ovarian Leiomyoma

A 32-year-old woman was admitted for termination of her 6-week pregnancy at her request. However, pelvic examination followed by transvaginal ultra-sonography (TVU) revealed an adnexal mass complicating pregnancy and requiring surgical intervention that was carried out after termination of pregnancy. At laparotomy, left salpingooophorectomy was performed and histologic examination revealed a leiomyoma arising primarily in the ovary. C. Gürkan Zorlu, MD, 17. Sokak 96/9, Bahçelievler 06490, Ankara (Turkey) Introduction Leiomyoma arising primarily in the ovary is an extremely rare tumor. However, many cases pass unrecorded [1], perhaps because ovarian leiomyomas are usually so small in size that they may be missed in routine evaluation of the surgical oophorectomy specimens [1, 2]We report a case of primary ovarian leiomyoma which was diagnosed after surgical intervention for adnexal mass complicating pregnancy. Case Report A 32-year-old woman, gravida 5, para 4, was admitted to family planning service of Dr. Zekai Tahir Burak Women’s Hospital for termination of her 6-week gestation at her request. Her past history was unremarkable. Physical examination and laboratory data were normal. However, pelvic examination revealed a solid, irregular mass on the left side which could be clearly felt separate from the uterus. Although she had no complaint about the mass, she was operated on after termination of her pregnancy. At laparotomy, a solid tumor of the left ovary was detected distinctly separate from the uterus. There was no adhesion or infiltration to the surrounding structures. Left salpingo-oophorectomy was performed and frozen sectioning revealed a benign tumor at the time of operation. The resected left ovary and adnexa were submitted for extensive sectioning and final examination. The tumor, weighing 930 g, measured 14 cm in length and 9 cm in maximum width. The tumor appeared hard except for one softened single nodule measuring 4 cm in length and 3 cm in width, near the inferior surface. The surface was smooth and shiny. On section, the tumor was mainly hard and firm and whitegray in color but the cut surface of the tumor traversing the above-mentioned nodule revealed many small cysts which were sharply delineated from the tumor. Sections from various portions of the tumor were prepared and stained with hematoxylin-eosin. In all sections, the tissue was composed of typical smooth muscle cells with ovoid nuclei. They formed strands and bundles arranged in the whorled pattern, characteristic of a leiomyoma (fig. 1). Thus, Masson’s trichrome, a more specific stain, was used to confirm the diagnosis of this rare tumor: the tumor cells stained bright red thus confirming that the tumor indeed was a leiomyoma. The nodule with many small cysts was diagnosed as the ovary, surrounded by the tumor (fig. 2). Discussion Although its precise histogenesis is uncertain, primary ovarian leiomyoma probably originates from smooth muscle present in the walls of blood vessels which supply the ovaries or extremities of the ovarian ligament [2]. However, many other sites (undifferentiated germ cells in the ovarian stroma [3], remnants of the wolffian body [4], smooth muscle itself within the ovary and its ligaments [5, 6], stroma of endometriosis [7]) have been proposed as the origin of these tumors. © 1993 S. KargerAG, Basel 0378-7346/93/0363-0191 $2.75/0 1 “· I* ; • – .