Epithelioid endometrial and endometrioid stromal tumors: a report of four cases emphasizing their distinction from epithelioid smooth muscle tumors and other oxyphilic uterine and extrauterine tumors

Our plain-English summary of Epithelioid endometrial and endometrioid stromal tumors: a report of four cases emphasizing their distinction from epithelioid smooth muscle tumors and other oxyphilic uterine and extrauterine tumors, by E. Oliva, P.B. Clement, R.H. Young (International Journal of Gynecological Pathology, 2002).

The study

• Authors: E. Oliva, P.B. Clement, R.H. Young
• Journal: International Journal of Gynecological Pathology
• Published: 2002;21(1):48-55
• Type of article: Case report
• Cited by: 56 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Three endometrial and one extrauterine endometrioid stromal tumors (three sarcomas and one stromal nodule) with a prominent component of epithelioid cells with abundant eosinophilic cytoplasm are described. The patients were 39, 48, 56 and 86 years of age. The endometrial sarcomas were described grossly as an ill-defined tan nodule and "ragged and papillary," respectively, and had the typical infiltrative pattern of low-grade endometrial stromal sarcoma. The stromal nodule was a 13-cm, well circumscribed, yellow, fleshy mass. The extrauterine tumor was probably primary in the sigmoid colon. Oval to polygonal epithelioid cells with abundant eosinophilic cytoplasm accounted for 50% to 90% of the tumor cells. The cytoplasm was granular in one case. None of the tumors contained cells with a rhabdoid appearance. Nuclear and other features did not differ from those of usual endometrial-endometrioid stromal tumors except in one case in which there was greater nuclear pleomorphism. There was strong diffuse cytoplasmic immunoreactivity of all four tumors for vimentin and for CD10 in three of three tumors tested, as well as extensive and moderate reactivity for NK1/C3 and focal weak reactivity for CD68 in two of three tumors tested. Muscle actin positivity was very focal to extensive and weak to strong in all three tumors tested, mainly in the epithelioid areas; alpha-smooth muscle actin was focally to extensively positive in the epithelioid areas of two of three tumors tested; and focal strong desmin positivity (interpreted as indicating smooth muscle metaplasia) was found in the epithelioid areas of one of four tumors. A vaginal recurrence in one case had similar cytologic features to the primary tumor but when examined initially in the absence of adequate history posed diagnostic difficulty, as did evaluation of the uterine tumor in two other cases and the extrauterine tumor in the final case. The differential in these cases is primarily with an epithelioid smooth muscle tumor when they are uterine primaries. The typical infiltration facilitates this distinction in the cases of endometrial stromal sarcomas, but this feature is usually only evident in hysterectomy specimens. In limited samples such as biopsy or curettage specimens, and in some cases of recurrent tumor, awareness that endometrial-endometrioid stromal tumors can have epithelioid cells is crucial in the formulation of the differential diagnosis. Diverse oxyphilic tumors, including deciduoid malignant mesothelioma, can potentially be in the differential diagnosis with extrauterine (endometrioid) stromal sarcomas with epithelioid cells. Immunohistochemical evaluation may potentially provide major aid in diagnosis.

In plain English

This article was a report of four cases. It did not study asbestos or any other exposure. Mesothelioma appeared only as a possible source of confusion in diagnosis. The authors described three tumors of the endometrial stroma (the supporting tissue of the uterine lining) and one similar tumor outside the uterus. The patients were women aged 39, 48, 56 and 86. Most of the tumor cells had abundant pink-staining (eosinophilic) cytoplasm, described as epithelioid or oxyphilic: about 80% to 90% in three cases and about 50% in the other. All four tumors stained strongly for vimentin, and all three tested stained strongly for CD10. Desmin, a muscle marker, was positive in only one of four, in focal areas. In all four cases these cells caused problems in diagnosis. One patient had a vaginal recurrence 11 months after surgery. The authors noted that a deciduoid mesothelioma could be considered for the tumor outside the uterus, especially in small biopsies. The authors concluded that this cell type may cause confusion with epithelioid smooth muscle tumors and other tumors.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case series (report of four cases), with microscopic and immunohistochemical review
• Who was studied: Four women, aged 39, 48, 56 and 86. They had three uterine (endometrial) stromal tumors (two endometrial stromal sarcomas and one endometrial stromal nodule) and one extrauterine endometrioid stromal sarcoma, probably arising in the bowel. Three cases came from one author's consultation files and one from Massachusetts General Hospital. No dates were given.
• Main results:
  • Epithelioid cells with abundant cytoplasm made up about 80% to 90% of tumor cells in three cases and about 50% in the fourth.
  • All four tumors stained strongly and diffusely for vimentin, and all three tumors tested stained strongly and diffusely for CD10.
  • Desmin staining was negative in three tumors and focally strongly positive in the epithelioid areas of the fourth.
  • In all four cases the oxyphilic cells caused problems in diagnosis.
  • In one patient (the 56-year-old), a vaginal polyp found 11 months after surgery was a recurrence of the tumor.
  • For the extrauterine tumor, which had cells with a deciduoid appearance, the authors stated that the differential diagnosis may include deciduoid mesothelioma.
• The authors' conclusion: The authors concluded that a prominent component of epithelioid cells with abundant oxyphilic cytoplasm in these tumors may cause confusion with the more common epithelioid smooth muscle tumor and potentially other tumors.
• Limitations the authors state:
  • The exact site of origin of the extrauterine tumor could not be proven, because of how far both the tumor and the associated endometriosis had spread.

Topics

Medical terms in this study, explained in our Lexicon: Epithelioid, Sarcoma, Eosinophilic, Rhabdoid, Nuclear Pleomorphism, Desmin, Biopsy, Differential Diagnosis.

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