作者：李再波 赵澄泉

翻译：陈健

摘要：子宫或卵巢去分化子宫内膜样腺癌（DEAC）特征表现为低级别子宫内膜样癌与未分化癌（UC）共存，后者可见由中等大小单形性上皮细胞构成的实性片状结构。由于对这种混合性癌的认识不足，UC中的实性区域常被误认为FIGO 3级子宫内膜样癌的实性形式。DEAC是一种临床侵袭性肿瘤，准确诊断才能制定恰当的治疗方案。我们回顾了DEAC的诊断经验，并与3级子宫内膜样癌进行比较，对比两者在临床病理学、形态学和免疫组化特征方面的差异。我们的研究结果显示，DEAC是一种临床侵袭性肿瘤，诊断时已处于晚期，血管浸润见于73%的病例，淋巴结转移见于46%的病例。38%的病例还存在远处转移。随访结果显示，所有病例在诊断后3年内出现复发或转移，仅1例患者在诊断后3年仍保持无瘤生存状态。形态学上，DEAC中的UC成分由弥漫片状/实性巢状排列的中等大小上皮细胞构成，胞质稀少至中等量，具有一致的空泡状核，核仁不明显。虽然DEAC中的UC成分不同程度阳性表达CK、EMA和ER，但大多数病例不表达PAX8（仅1例除外）。与之不同的是，DEAC中的高分化成分和3级子宫内膜样癌的实性成分均保留对这些标记物的表达。我们的结果提示，DEAC的临床病理学特征显著不同于3级子宫内膜样腺癌，结合免疫组化染色有助于两者的鉴别。

Abstract: Dedifferentiated endometrioid adenocarcinoma (DE-AC) of the uterus or ovary is characterized by the coexistence of low-grade endometrioid adenocarcinoma and an undifferen-tiated carcinoma (UC) with solid sheets of medium-sized mo-notonous epithelial cells. This admixed carcinoma has not been widely recognized, because the solid areas of UC have usually been misdiagnosed as a solid form of FIGO grade 3 endome-trioid adenocarcinoma. These tumors have been shown to be clinically aggressive; therefore, accurate diagnosis is necessary for proper patient management. We reviewed our experience with DEACs and compared them with grade 3 endometrioid carcinomas regarding their clinicopathologic, morphologic, and immunohistochemical features. Our results indicate that DEACs are clinically aggressive tumors presented at advanced stages with vascular invasions in 73% and lymph node metastases in 46%. Thirty-eight percent of cases also showed distal meta-stases. Clinical follow-up data revealed that all patients had ei-ther recurrent or metastatic diseases within 3 years of diagnosis, except 1 patient who remained disease free for 3 years after diagnosis. Morphologically, UC components of DEACs were composed of diffuse sheets/solid nests of medium-sized epithelial cells with scant to moderate cytoplasm, uniform vesicular nuclei, and inconspicuous nucleoli. Although UC components of DE-ACs are variably positive for cytokeratin, EMA, and ER, they are mostly negative for PAX8, except 1 case. Instead, well-dif-ferentiated components of DEACs and solid grade 3 endome-trioid carcinoma retained all these markers. Our results indicate that DEACs exhibit significantly different clinicopathologic features from grade 3 endometrioid adenocarcinoma, and a combination of immunohistochemical stains can be helpful to differentiate them from each other.

图1. DEAC形态学。A,1/2级子宫内膜样癌成分(H&E,100X)。B,未分化成分伴巢状生长结构(H&E,100X)。C,未分化成分伴巢状生长结构(H&E,200X)。D,未分化成分伴横纹肌样细胞(H&E,400X)。E,未分化成分伴肿瘤性坏死(H&E,200X)。F,未分化成分伴淋巴血管浸润(H&E,20X)。

 图2. 一例DEAC的组织形态学和免疫组化染色。A,DEAC伴未分化成分（右）和高分化子宫内膜样成分（左）(100X)。B,AE1/3免疫染色显示高分化子宫内膜样成分，但未分化成分仅呈斑片状弱阳性(100X)。C,Cam5。2免疫染色，高分化子宫内膜样成分呈弥漫强阳性，但未分化成分仅罕见阳性(100X)。D,EMA免疫染色，高分化子宫内膜样成分呈阳性，但未分化成分阴性(100)。E,ER免疫染色，高分化子宫内膜样成分阳性，未分化成分弱阳性(100X)。F,PAX8免疫染色，高分化子宫内膜样成分和未分化成分均阳性(100X)。

图3. FIGO3级子宫内膜样癌的组织形态学和免疫组化染色。A,3级子宫内膜样癌伴腺样结构和实性成分(HE,100X)。B,PAX8免疫染色，腺和实性成分均呈阳性(100X)。C,Cam5。2免疫染色，腺和实性成分均呈阳性(100X)。D,EMA免疫染色，仅腺样区域阳性，实性区域阴性(100X)。