This is an outside consultation case.

There are diffuse infiltrating epithelioid cells in the lamina propria. The cell borders are not clear.  Some cells have clear cell changes (胞浆中有空泡),  间质内有少量的出血，结合病史要除外肾细胞癌.

Other common entities in the differential diagnosis include:

低分化腺癌(胃印戒细胞癌)

间叶源性肿瘤

恶黑

淋巴瘤

Histocytic lesions

Based on the morphological impression, a panel of immunostains was performed:

CK (focally, weakly +)

EMA (--)

Vimentin(focally +)

S-100(strongly ++)

CD45(--)

CD68(--).

Subsequently, HMB45 was  performed:

HMB45 (++).

When I called to the clinician for the pathology results, he then stated that the patient also had a “mole” removed two years ago, but he did not have a pathology report of the “mole”.

Based on all the above information, it is most consistent with a metastatic melanoma (恶黑).

This is an example that 恶黑 can mimic many diseases. Whenever, you are not sure about an atypical lesion, 恶黑 should be always considered in the differential diagnosis.

 没有见到明确溃疡  肾细胞癌12年是否与这有关 原来是什么类型 要排除转移 

 恶性肿瘤 是上皮性还是间叶性 还需做一些工作

看来是溃疡边缘取的活检，取得很准。

恶性是肯定的了，但是不象是普通的胃癌或肾细胞癌。

排列方式象间叶源性肿瘤，核仁看起来又象是低分化腺癌。

需要免疫组化进一步鉴别诊断。

CK7、CK20、VIM、RRC、CDX2、S-100、CD45

 转移性肾细胞癌、胃印戒细胞癌和胃黄斑瘤相鉴别。

IHC标记CK、vimentin、CD68等。组织化学AB-PAS（鉴定印戒细胞）和胶体铁染色（鉴定肾嫌色细胞癌）。

 未见溃疡性病变，在浅表腺体之间弥漫排列的细胞有一定的异型性，但相对温和，间质内有少量的出血，结合病史首先要除外肾细胞癌的转移，还要与溃疡的修复性改变相鉴别; IHC 标记CD10，CD68， vimentin。

期待最终的结果。

见过一些肿瘤术后化疗，引致新的癌症，要么是新发的原发癌，要么就是淋巴瘤。化疗药物既可以治癌，要可以致癌。典型的例子是环磷酰胺，用于治疗膀胱肿瘤或癌前驱病变，又可以在治疗后新发原发癌。

本例的细胞核有异型性，局灶还可以见到核分裂，不是转移性肾细胞癌就是胃低分化腺癌。

不是正常粘膜间质，细胞异型明显，排列紊乱，部分核偏位，考虑印戒细胞癌。

This is an example that 恶黑 can mimic many diseases. Whenever, you are not sure about an atypical lesion, 恶黑 should be always considered in the differential diagnosis.

非常感谢谈老师提供如此经典的病例和如此深刻的总结！