Extrauterine adenomyoma of the liver with a focally cellular smooth muscle component occurring in a patient with a history of myomectomy: case report and review of the literature

Abstract

Since first reported in 1986, 14 cases of extrauterine adenomyoma have been reported in the English literature, most often occurring in the ovaries. In this report, we present the first case of extrauterine adenomyoma involving the liver in a 29-year-old woman who presented with a 2-year history of low back pain with recent worsening and a history of laparoscopic myomectomy 5 years previously. Gross inspection of the specimen revealed a subcapsular mass that had a well-circumscribed margin with the adjacent liver tissue. By histopathologic examination, the multilobular mass was composed of a smooth muscle component and benign endometrioid glands and stroma. The smooth muscle component was focally cellular, and the endometrioid glands had secretory features. Both the smooth muscle component and endometrioid tissue were positive for ER and PR. The smooth muscle component was also positive for desmin and SMA, while the endometrioid stroma was positive for CD10. Other extrauterine lesions composed of a mixture of smooth muscle tissue and heterotopic endometrioid tissue, including endometriosis with a smooth muscle component, leiomyomatosis/leiomyomas associated with endometriosis and uterus-like masses, should be included in differential diagnoses. The patient was free from recurrence 5 months after liver tumor resection.

Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1327125766102291.

Figure 1

Contrast-enhanced CT showed a heterogeneously enhanced mass (arrow) in the peripheral zone of the posterior right lobe of the liver.

Figure 2

The cut surface showed a white-gray mass with cysts and foci of congestion and hemorrhage varying in diameter from 0.5 to 4 mm.

Figure 3

Microscopic features (hematoxylin-eosin stain). A, Histopathologic examination revealed a subcapsular mass. The multilobular mass had a well-circumscribed margin with the adjacent liver tissue. B, Irregular endometrioid glands and cysts were haphazardly scattered among the smooth muscle bundles. Variable amounts of blood/congestion and hemorrhage, dense fibrosis, and hemosiderin-laden macrophages were associated with the endometrioid tissue. C, The whorled intersecting smooth muscle component was focally cellular. D, The endometrioid cysts were typically lined by a single layer of columnar cells and had secretory features.

Figure 4

Immunohistochemical staining was performed. The smooth muscle component and the endometrioid tissue were both positive for ER (A) and PR (B). The endometrioid stroma surrounding the endometrioid glands was positive for CD10 (C), while the smooth muscle component was positive for desmin (D).