女，42岁 右后背部肿块

灰黄、灰褐结节状组织3.0CM*2.5CM*2.0CM大小，切面灰白、质软。

本例图片采用麦克奥迪MoticBA410显微镜+MoticamPro285A摄像头采集制作。 

点评专家：焦宇飞（102楼  链接：>>点击查看<< ）

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本例以大片的凝固性坏死为显著特点，只残留小块的瘤组织岛。

上面各位同仁的意见很有道理，但本人却想问一下病史：患者有无鼻咽癌等病史？

在排除转移性低分化癌之后，才考虑：

恶性淋巴造血系统肿瘤，如间变大细胞淋巴瘤、朗格汉斯细胞组织细胞肉瘤、FDCS等。

期待免疫组化结果和相关病史以协助诊断。

低倍镜下周围见淋巴细胞？和淋巴滤泡？

细胞有一定异型性

分化方向不确定？

免疫组化反应向肌？神经？纤维？

考虑血管瘤样纤维组织细胞瘤

考虑近端型上皮样肉瘤

首先考虑粒细胞肉瘤，需追问病史，淋巴瘤不除外。

严重支持 朗格汉斯细胞肉瘤

上皮样肉瘤

支持软组织肉瘤，粒细胞肉瘤可能性大，上皮样肉瘤、淋巴瘤也要排除，具体类型要靠免疫组化。等正确答案吧。

希望最终公布正确答案！

诊断：恶性肿瘤

          坏死及肉芽组织较多，其中深色的是肿瘤成分，瘤细胞上皮样，梁索状分布或聚巢，异型性显著，核分裂多见。其间血窦丰富。

 1.近端型上皮样肉瘤：坏死多但不在肿瘤中央？低倍下午明显结节状结构？

 2. 上皮样血管肉瘤：  血管丰富，细胞异形性明显。

 3.转移性神经内分泌癌/  分化差的神经内分泌癌？

 4.转移性低分化癌。

5. 绒癌？（转移？）要结合临床病史。

    以上均需依赖免疫组化鉴别诊断

commitit 

诊断：（右后背部肿块）上皮样肉瘤

诸位老师：此例是（女，42岁 ，右后背部肿块），而不是男性哟！

First, I am just a beginner in pathology. At the same time, I am practicing English. Please do not laugh at me:)

First Impression and pattern recognition: Extensive necrosis and high mitotic index with primitive cytologic features, consistent with small round blue cell tumor? Is there some hint of rossette formation or is it my imagination?

Cytology: The nuclear chromatin is highly open with apparent irregular nuclear membranes and inconspicuous nucleolus. Small to modest amount of eosinophilic cytoplasm are present, while cell borders are poorly defined. Size of the nucleus are variable but more on the side of small.

Background: Some lymphocytes, neutrophils and eosinophils? There is one area with focally increased amount of blood vessels from the background without obvious red cell extravasation. Some small sized vessels were intermingled with tumor cells. 

Diagnostic reasoning: Carcinoma and melanoma are unlikely. Lymphoma and sarcoma should be considered.

Myeloid sarcoma, due to cytologic features including open fine chromatin with irregular nuclear membranes, somewhat eosinophilic cytoplasm, and background of neutrophils and eosinophils

Langerhan cell histocytosis or sarcoma, possible but no prominent features of nuclear grooves are present.

Diffuse large B-cell lymphoma: possible but may see bigger nuclear size and more prominent nucleolus.

Anaplastic T-cell lymphoma: possible but no "Hallmark" cells seen

Follicular, interdigitating Dendritic cell sarcoma: possible but would be very unusual pattern.

Lymphoblastic lymphoma (including B, T, and blastic plasmacytoid dendritic cell): possible but nucleus should be more uniform round

List of sarcomas would include

Ewing's/PNET,

Synovial sarcoma,

Rhabdosarcoma,

Round cell liposarcoma,

maybe even MPNST. 

Final diagnosis: Poorly differentiated small round blue cell tumor, differential including above entities, favoring myeloid sarcoma.

Would like to do following IHC in the first round: Keratin, EMA, MPO, CD15, CD45, desmin, s100, sma, CD34

Possible in the future: CD23, CD1a, Granzyme B and many others:)

Finally, thank you for the interesting case!!!

1、上皮样肉瘤

2、上皮样平滑肌肉瘤。

诊断：（右后背部肿块）上皮样肉瘤

诊断依据：（1）患者男性，42岁，后背部软组织肿块；

                  （2）低倍镜下示肿瘤大部分地图样坏死，瘤细胞弥漫性浸润；高倍镜下示瘤细胞异型性明显，呈圆形及卵圆形，核仁易见。散在分布少量嗜酸性粒细胞，核分裂像较多；

                  （3）周边伴有肌纤维母细胞的反应性增生；部分区域肿瘤细胞围绕血管呈浸润性生长；

                  免疫组化：AE1/AE3、Vimentin、LCA、CD1a、S-100、CD68、CD21、CD23、CD3、CD20、MPO、粒酶B、SMA、Desmin、HMB45、KI-67

鉴别诊断：（1）滤泡树突细胞肉瘤：形态类似炎性假瘤，免疫组化FDC的标记物阳性；

                    （2）梭形细胞癌，

                  （3）肌源性肉瘤：结合免疫组化可以鉴别，不做为首要鉴别诊断；

                  （4）淋巴造血系统其它肿瘤：除外上述肿瘤后需要补做IHC鉴别

                   （5）单向分化滑膜肉瘤。

上皮样肉瘤

淋巴瘤？

粒细胞肉瘤

同意2楼意见；淋巴瘤要排外

1.朗格汉斯细胞肉瘤,2.低分化癌。

首先应除外转移的可能，个人考虑低分化的癌，因坏死比较严重，确诊还需免疫组化。