A 53-yr-old woman who presented with elevated renal indices was discovered to have a 4.5 cm right renal mass and an incidental 9.7 cm left ovarian mass on imaging studies. She underwent a partial nephrectomy and bilateral salpingo-oophorectomy, revealing a chromophobe renal cell carcinoma and an unusual ovarian neoplasm with epithelioid cells displaying prominent signet ring cell-like morphology. Immunohistochemical analysis of the ovarian neoplasm demonstrated that the tumor cells were diffusely immunoreactive for smooth muscle markers and negative for all tested cytokeratins and epithelial membrane antigen. On the basis of these results, the tumor was interpreted as an unusual epithelioid smooth muscle neoplasm with extensive signet ring cell-like features. Along with primary ovarian signet ring stromal tumors and sclerosing stromal tumors, this example adds epithelioid smooth muscle neoplasms with unusual cytologic alterations to the list of uncommon nonepithelial tumors that can simulate metastatic signet ring cell carcinoma (Krukenberg tumor) in the ovary.
Department of Pathology, The Johns Hopkins Medical Institute, Baltimore, Maryland (D.X., A.A.B., C.L., A.R., R.V., B.M.R.)
D.X. and A.A.B contributed equally.
Supported by Career Development Award by the Cervical Cancer SPORE program at Johns Hopkins (D.X.).
The authors declare no conflict of interest.
Address correspondence and reprint requests to Deyin Xing, MD, PhD, Department of Pathology, The Johns Hopkins Medical Institute, 401 N. Broadway, Weinberg 2242, Baltimore, MD 21231. E-mail: email@example.com.