This uterine tumor was largely comprised of epithelial-like cells forming nests, cords and tubules -- garnering a diagnosis of UTROSCT.
The darkly staining epithelial-like cells form almost solid areas.
The neoplastic cells have prominent nucleoli. The spindled morphology and cellularity are almost like a stromal sarcoma.
Tubule formation and trabeculae can be appreciated here.
If the tumor were composed of areas such as this image, you might consider the diagnosis of ESTSCLE. Note the trabeculae of epithelial-like cells percolating through the myometrium. However, the tumor in its entirety was mostly composed of sex cord-like elements.
All UTROSCT demonstrate calretinin positivity.
Both UTROSCT and ESTSCLE demonstrate ER positivity, and thus, would not help differentiate between the two entities (Irving).
Uterine tumors which resembled sex cord tumors of the ovaries were reviewed by Clement and Scully in 1976 and divided in two groups. Group 1 tumors were were endometrial stromal tumors with sex-cord like elements (ESTSCLE), and group 2 tumors were uterine tumor resembling ovarian sex cord tumor (UTROSCT). The main difference between ESTSCLE and UTROSCT is the amount of sex cord elements comprising the tumor. UTROSCT is predominantly composed of sex cord elements, whereas ESTSCLE is predominately an endometrial stromal tumor with a minor component of sex cord elements (Czernobilsky, Giordano).
In ESTSCLE , prognosis is dependent on the underlying endometrial stromal tumor, which can range from benign to malignant. UTROSCT is mostly benign, but has a tendency to recur and thus, experts believe it is more accurately described as a tumor with low-grade malignant potential (Czernobilsky).
Grossly, UTROSCT can be submucosal, intramural or subserosal. The masses are usually well-circumscribed with pushing or rarely, infiltrating borders.
Histologically, epithelial-like cells arranged in cords, nests, anastomosing trabeculae and tubules are found comprising 10 to 40% of ESTSCLE. In contrast, these epithelial-like (sex cord) elements comprise most of the tumor in UTROSCT. Basically UTROSCT looks like a granulosa cell tumor or Sertoli cell tumor of the ovary, but located in the myometrium. Recent studies have shown that UTROSCT displays a vast array of architectural patterns and features seen in sex cord tumors of the ovary including reiform pattern, glomeruloid and cystic structures, granulosa cell tumor-like areas with Call-Exner bodies (Czernobilsky, Irving).
IHC studies conducted by Irving comparing ESTSCLE (3 cases) and UTROSCT (5 cases) show that UTROSCT demonstrate positivity for calretinin in addition to positivity for one of these markes: inhibin, CD99, Melan A). In contrast, ESTSCLE demonstrate positivity with one of the markers (calretinin or CD 99). This supports the prevailing opinion that UTROSCT are polyphenotypic uterine tumors with true sex cord differentiation, most likely arising from pluripotent mesechymal cells (Czernobilsky, Irving).
Usually occurs in middle-aged women (average age 50). Presents with enlarged uterus and abnormal bleeding.
UTROSCT is considered to be a more indolent tumor than ESTSCLE. Note that endometrial stromal tumors can be malignant and present at advanced stages. No distant metastasis or extrauterine spread have been reported in UTROSCT.
Czernobilsky B. Uterine tumors resembling ovarian sex cord tumors: an update. Int J Gynecol Pathol. 2008 Apr;27(2):229-35.
Giordano G, Lombardi M, Brigati F, Mancini C, Silini EM. Clinicopathologic features of 2 new cases of uterine tumors resembling ovarian sex cord tumors. Int J Gynecol Pathol. 2010 Sep;29(5):459-67.
Irving JA, Carinelli S, Prat J. Uterine tumors resembling ovarian sex cord tumors are polyphenotypic neoplasms with true sex cord differentiation. Mod Pathol. 2006 Jan;19(1):17-24.
Staats PN, Garcia JJ, Dias-Santagata DC et al. Uterine tumors resembling ovarian sex cord tumors (UTROSCT) lack the JAZF1-JJAZ1 translocation frequently seen in endometrial stromal tumors. Am J Surg Pathol. 2009 Aug;33(8):1206-12.