免疫组化结果：

Ki-67 20%+、CK—、LCA—、CD43—、CD20—、CD3—、EMA—、CD34—、CD117—、S100—、HMB45—、DESMIN+++(弥漫性)、SMA阴性至灶状阳性、ACTIN—、Caldesmon—、Calponin—、MyoD1—、Myogenin—、Myoglobin—、神经内分泌标记阴性。

最后诊断：上皮样平滑肌肉瘤

患者术后3个月死亡。

一般来讲，SMA是平滑肌肿瘤最敏感的标记物，如果Desmin弥漫+的平滑肌肿瘤，SMA一般都有较好的表达，而且是分化较好的平滑肌肿瘤，其它平滑肌标记物常会表达；而Desmin是横纹肌肉瘤最敏感的标记物，MyOD1和Myogenin在一小部分横纹肌肉瘤表达不好或阴性，尤其在横纹肌分化较明显的横纹肌肉瘤表达较弱，SMA常阴性或小灶+。本例，Desmin弥漫强+，SMA-/小灶+，其它指标均-，说明是有明确分化方向的肉瘤，形态表现为横纹样特征，而且年轻。综上，更加符合（具有横纹样特征）横纹肌肉瘤，而不太支持好发于中老年人的平滑肌肉瘤。个人愚见，仅供参考！

DESMIN+++(弥漫性)、SMA阴性至灶状阳性、Caldesmon—、Calponin—、MyoD1—、Myogenin—免疫组合更倾向横纹肌肉瘤，请问此例如何与横纹肌肉瘤鉴别？

对于此例读片会时也存有争议，DESMIN在平滑肌肉瘤和横纹肌肉瘤均可表达，而其余的横纹肌标记均阴性（MyoD1—、Myogenin—、Myoglobin—），所以诊断为平滑肌肉瘤。（个人愚见）

高级别软组织肉瘤伴肌源性分化。无法再进一步。

术后3个月就死亡，进展太快了。不一定是死于肿瘤吧，可能是并发症死亡？

 本例很可能就是上皮样炎性肌纤维母细胞肉瘤
Epithelioid Inflammatory Myofibroblastic Sarcoma: An Aggressive Intra-abdominal Variant of Inflammatory Myofibroblastic Tumor With Nuclear Membrane or Perinuclear ALK
Mariño-Enríquez, Adrián MD*,&;; Wang, Wei-Lien MD&;,§; Roy, Angshumoy MD, PhD¶; Lopez-Terrada, Dolores MD, PhD¶; Lazar, Alexander J.F. MD, PhD&,§; Fletcher, Christopher D.M. MD, FRCPath*; Coffin, Cheryl M. MD∥; Hornick, Jason L. MD, PhD*

AbstractInflammatory myofibroblastic tumor (IMT) is a mesenchymal neoplasm of intermediate biological potential, which may recur and rarely metastasize. Pathologic features do not correlate well with behavior. Approximately 50% of conventional IMTs harbor ALK gene rearrangement and overexpress ALK, most showing diffuse cytoplasmic staining. Rare IMTs with a distinct nuclear membrane or perinuclear pattern of ALK staining and epithelioid or round cell morphology have been reported. These cases pursued an aggressive clinical course, suggesting that such patterns may predict malignant behavior. We describe 11 cases of IMT with epithelioid morphology and a nuclear membrane or perinuclear pattern of immunostaining for ALK. Ten patients were male and 1 was female, ranging from 7 months to 63 years in age (median, 39 y). All tumors were intra-abdominal; most arose in the mesentery or omentum, measuring 8 to 26 cm (median, 15 cm). Six tumors were multifocal at presentation. The tumors were composed predominantly of sheets of round-to-epithelioid cells with vesicular nuclei, large nucleoli, and amphophilic-to-eosinophilic cytoplasm. In all cases, a minor spindle cell component was present. Nine tumors had abundant myxoid stroma. In 7 cases neutrophils were prominent and in 3 cases lymphocytes were prominent. Plasma cells were often absent. Median mitotic rate was 4/10 HPF; 6 tumors had necrosis. By immunohistochemistry, all tumors were positive for ALK, 9 tumors showing a nuclear membrane staining pattern and 2 tumors showing a cytoplasmic pattern with perinuclear accentuation. Other positive markers were desmin (10 of 11), focal smooth muscle actin (4 of 8), and CD30 (8 of 8). All tumors were negative for MYF4, caldesmon, keratins, EMA, and S-100. Fluorescence in situ hybridization was positive for ALK gene rearrangement in 9 cases, and in 3 cases tested, a RANBP2-ALK fusion was detected by reverse transcription polymerase chain reaction. Ten patients underwent surgical resection; 1 patient was inoperable. Follow-up was available for 8 patients and ranged from 3 to 40 months (median, 13 mo). All patients experienced rapid local recurrences; 4 patients had multiple recurrences. Eight patients were treated with postoperative chemotherapy; 2 patients received additional radiotherapy. Two patients also developed metastases (both patients developed metastases to the liver; 1 patient developed metastases to the lung and lymph nodes as well). Thus far, 5 patients died of disease, 2 patients are alive with disease, and 1 patient, treated with an experimental ALK inhibitor, has no evidence of disease. In summary, the epithelioid variant of IMT with nuclear membrane or perinuclear ALK is a distinctive intra-abdominal sarcoma with a predilection for male patients. Unlike conventional IMT, abundant myxoid stroma and prominent neutrophils are common. These tumors pursue an aggressive course with rapid local recurrences and are frequently fatal. We propose the designation “epithelioid inflammatory myofibroblastic sarcoma” to convey both the malignant behavior of these tumors and their close relationship with IMT.

学习了！

 具有横纹样细胞形态的恶性肿瘤：除楼上提到的之外，还要考虑恶性肾外横纹样肿瘤、上皮样肉瘤、上皮样血管肉瘤、横纹肌肉瘤、透明细胞肉瘤、间变大细胞淋巴瘤等，标记一下再发报告了

 肿瘤细胞弥漫性生长浸润性，肿瘤细胞大小不一致，呈上皮样，核仁明显，部分血管内皮细胞异型，出现怪异型 的大细胞，异型非常明显，间质血管很丰富，出血。

 考虑血管肉瘤、上皮样间质瘤、恶黑、恶性纤维组织细胞瘤。

同意

学习了

恶性软组织肿瘤，细胞粘附性差，细胞围绕血管生长，部分细胞核偏位，异型明显，红核仁易见，部分单个细胞中有红细胞，考虑上皮样血管肉瘤；恶黑。

学习了

血管太丰富了

GIST、生殖细胞肿瘤、恶黑、淋巴造血系统肿瘤、恶性间皮瘤

好病例

没有组化结果我会考虑上皮样肉瘤，大红核仁太多了。

上皮样肉瘤