【病理资讯】未分化/去分化子宫内膜癌的肉瘤转化：尚未识别的组织学和诊断陷阱

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.

原文献DOI:

doi: 10.1097/PGP.0000000000000635

未分化/去分化子宫内膜癌的肉瘤转化：尚未识别的组织学和诊断陷阱

摘要

未分化/去分化癌是一种侵袭性子宫内膜癌，至今仍未被广泛认识，约占所有子宫内膜恶性肿瘤的9％。我们描述了3例未分化成分与肉瘤分化相关的病例，其特征为梭形细胞2例和异源性恶性软骨1例。3例中有2例通过免疫组织化学证实错配修复（MMR）缺陷。这种现象以前没有被正式报道过并有误诊的可能性，尤其是在活检样本中。鉴别诊断可能包括子宫内膜间质肉瘤和呈梭形形态的3级子宫内膜样腺癌。我们回顾了当前的文献并提供了解决鉴别诊断的策略，建议的一组抗体包括EMA，E-钙黏着蛋白和错配修复蛋白，因为大约50％的病例显示错配修复表达的丧失。

I 译者点评(Comments)

未分化/去分化子宫内膜癌是子宫内膜癌的一个特殊类型，其预后较2或3级子宫内膜样癌差。如本文所述，其肉瘤转化提示恶性混合苗勒氏瘤的另一种发病机理。有必要做进一步的病例研究以确认作者的结论。

II 文献译者