Sarcomatous Transformation in Undifferentiated/Dedifferentiated Endometrial Carcinoma: An Underrecognized Phenomenon and Diagnostic Pitfall

Vroobel, Katherine M.，Attygalle, Ayoma D.

International Journal of Gynecological Pathology: September 2020 - Volume 39 - Issue 5 - p 485-492

ABSTRACT

Undifferentiated/dedifferentiated carcinoma is an aggressive endometrial carcinoma which remains underrecognized but may account for up to 9% of all endometrial malignancies. We describe 3 cases in which the undifferentiated component was associated with sarcomatousdifferentiation, characterized by spindled cells in 2 cases and heterologous malignant cartilage in 1 case. Two of the 3 cases demonstrated mismatch repair deficiency by immunohistochemistry. This phenomenon has not previously been formally reported and increases the likelihood of misdiagnosis, especially within biopsy samples; differential diagnoses may include endometrial stromal sarcoma and grade 3 endometrioid adenocarcinoma with spindled morphology. We review the current literature and provide strategies for resolving the differential diagnoses, with a suggested panel of antibodies which includes EMA, E-cadherin, and mismatch repair proteins as approximately 50% of cases show loss of mismatch repair expression.

原文獻(xiàn)DOI:

doi: 10.1097/PGP.0000000000000635

未分化/去分化子宮內(nèi)膜癌的肉瘤轉(zhuǎn)化：尚未識(shí)別的組織學(xué)和診斷陷阱

摘要

未分化/去分化癌是一種侵襲性子宮內(nèi)膜癌，至今仍未被廣泛認(rèn)識(shí)，約占所有子宮內(nèi)膜惡性腫瘤的9％。我們描述了3例未分化成分與肉瘤分化相關(guān)的病例，其特征為梭形細(xì)胞2例和異源性惡性軟骨1例。3例中有2例通過免疫組織化學(xué)證實(shí)錯(cuò)配修復(fù)（MMR）缺陷。這種現(xiàn)象以前沒有被正式報(bào)道過并有誤診的可能性，尤其是在活檢樣本中。鑒別診斷可能包括子宮內(nèi)膜間質(zhì)肉瘤和呈梭形形態(tài)的3級(jí)子宮內(nèi)膜樣腺癌。我們回顧了當(dāng)前的文獻(xiàn)并提供了解決鑒別診斷的策略，建議的一組抗體包括EMA，E-鈣黏著蛋白和錯(cuò)配修復(fù)蛋白，因?yàn)榇蠹s50％的病例顯示錯(cuò)配修復(fù)表達(dá)的喪失。

I 譯者點(diǎn)評(píng)(Comments)

未分化/去分化子宮內(nèi)膜癌是子宮內(nèi)膜癌的一個(gè)特殊類型，其預(yù)后較2或3級(jí)子宮內(nèi)膜樣癌差。如本文所述，其肉瘤轉(zhuǎn)化提示惡性混合苗勒氏瘤的另一種發(fā)病機(jī)理。有必要做進(jìn)一步的病例研究以確認(rèn)作者的結(jié)論。

II 文獻(xiàn)譯者