Signet-ring Stromal Tumor of the Ovary: Clinicopathologic Analysis and Comparison With Krukenberg Tumor

Abstract

Signet-ring stromal tumor is a rare ovarian neoplasm that can mimic Krukenberg tumor because of the presence of signet-ring cells in both tumors. The clinicopathologic features of three signet-ring stromal tumors, one of which has been previously reported, were analyzed and compared with 10 Krukenberg tumors. Patients with signet-ring stromal tumor ranged in age from 34 to 41 years (mean: 36.7 years). All signet-ring stromal tumors were unilateral and stage IA, whereas 60% and 40% of Krukenberg tumors were bilateral or associated with extraovarian tumor, respectively. The signet-ring stromal tumors were devoid of epithelial differentiation (glands, nests, cords), whereas all of the Krukenberg tumors contained these epithelial structures at least focally. In contrast to signet-ring stromal tumors, the signet-ring cells of Krukenberg tumors were positive for periodic acid-Schiff with diastase and cytokeratins but negative for vimentin. The patients with signet-ring stromal tumors were alive without disease at follow-up interval of 1 month to 17.4 years (mean: 7.4 years). In summary, signet-ring stromal tumor is a rare, benign, ovarian tumor that may be mistaken for Krukenberg tumor. Although the combination of operative and histopathologic findings allow their distinction, histochemical and immunohistochemical stains may also be useful.

Signet-ring stromal tumor of the ovary: an extremely rare neoplasm

“…An additional subtle difference is that the cytoplasm of the signet-ring cells in SRST is white and appears "empty" whereas the cytoplasm of the Krukenberg tumor's signet-ring cells is characteristically pale and occasionally granular and eosinophilic (7). All the SRSTs are negative for PAS-D and mucicarmine, whereas the signetring cell component is positive in all the cases of Krukenberg tumor (6,7). Pancytokeratin is a very useful marker with no expression in the SRSTs but with consistent staining of Krukenberg tumors (6,7).…”

“…All the SRSTs are negative for PAS-D and mucicarmine, whereas the signetring cell component is positive in all the cases of Krukenberg tumor (6,7). Pancytokeratin is a very useful marker with no expression in the SRSTs but with consistent staining of Krukenberg tumors (6,7). Vimentin is also helpful in separating the two lesions, with positivity in SRSTs.…”

“…SRST of the ovary is a distinct type of stromal neoplasm that can mimic Krukenberg tumors. A negative history of carcinoma is not reliable in the distinction of SRST from Krukenberg tumor, as only a minority of patients with Krukenberg tumor have a history of carcinoma (6). Both these tumors may show multinodularity, hemorrhage, and necrosis (6).…”

“…A negative history of carcinoma is not reliable in the distinction of SRST from Krukenberg tumor, as only a minority of patients with Krukenberg tumor have a history of carcinoma (6). Both these tumors may show multinodularity, hemorrhage, and necrosis (6). Although neither nuclear atypia nor mitotic activity is helpful in distinguishing between these tumors, there are histological differences that can be evaluated on hematoxylene-eosin sections.…”

Primary signet-ring stromal tumor of the testis

“…Microscopically, this ovarian neoplasm is characterized by a proliferation of stromal spindle-shaped cells merged with rounded cells containing eccentric nuclei and single vacuoles, resembling signet-ring cells [1,3,[7][8][9][10]12]. The signet-ring cells may either be diffuse or represent only a focal change in an otherwise typical fibroma.…”