Cleveland Clinic, Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland, Ohio, USA.
Department of Pathology, CORPath, Ltd., Columbus, Ohio, USA.
Diagn Cytopathol. 2021 Jan;49(1):E24-E30. doi: 10.1002/dc.24565. Epub 2020 Aug 14.
Epithelioid hemangioendothelioma (EHE) is a rare malignant vascular tumor characterized by WWTR1-CAMTA1, t (1:3) (p36;q25) translocation in 90% of cases. Without prior EHE history, it can mimic other malignant effusions. Recently, CAMTA1 was published as an excellent immunohistochemical surrogate marker for molecular testing for WWTR1-CAMTA1 fusion in surgical specimens.
A 6-year retrospective search using our computer system was performed for cases diagnosed as EHE on effusion cytology and surgical specimens. The clinical presentation, cytologic findings and immunohistochemical stain results, including CAMTA1 were reviewed.
Four pleural and one peritoneal effusions were identified. The median age was 52 years with a female to male ratio of 3:2. Most patients presented with pulmonary symptoms. The cytologic features were non-specific easily mimicking other malignancies; especially in the absence of known prior malignancy. This was exemplified by one of our cases which was initially misdiagnosed as adenocarcinoma. Intracytoplasmic erythrocytes were present only on the cell blocks but not on cytology. The cytology cell blocks from patients with prior EHE confirmed on surgical biopsies stained positive for vascular markers (CD31, ERG) and CAMTA1.
The features of EHE in effusion are non-specific and a diagnostic pitfall in cytology. In the absence of prior EHE diagnosis, inclusion of this entity in the differential diagnoses and application of immunohistochemical stain panels will be prudent in avoiding a misdiagnosis. However, in cases with prior EHE diagnosis, CAMTA1 could serve as diagnostic marker; especially on limited cytology material. Additional studies will be helpful in supporting our results.
上皮样血管内皮细胞瘤（EHE）是一种罕见的恶性血管肿瘤，其特征在于 90%的病例存在 WWTR1-CAMTA1、t（1:3）（p36；q25）易位。在没有 EHE 病史的情况下，它可能模仿其他恶性积液。最近，CAMTA1 被发表为一种优秀的免疫组织化学替代标志物，可用于检测手术标本中 WWTR1-CAMTA1 融合的分子检测。
使用我们的计算机系统进行了一项为期 6 年的回顾性搜索，以确定在细胞学和手术标本中诊断为 EHE 的病例。回顾了临床特征、细胞学发现和免疫组织化学染色结果，包括 CAMTA1。
共发现 4 例胸腔积液和 1 例腹腔积液。中位年龄为 52 岁，男女比例为 3:2。大多数患者表现为肺部症状。细胞学特征是非特异性的，容易模仿其他恶性肿瘤；尤其是在没有已知先前恶性肿瘤的情况下。我们的一个病例就是一个例子，该病例最初被误诊为腺癌。仅在细胞块上存在胞质内红细胞，而在细胞学上则不存在。来自手术活检证实的先前 EHE 患者的细胞学细胞块染色阳性，表达血管标志物（CD31、ERG）和 CAMTA1。
在细胞学中，EHE 积液的特征是非特异性的，容易造成诊断陷阱。在没有先前 EHE 诊断的情况下，将该实体纳入鉴别诊断并应用免疫组织化学染色组将有助于避免误诊。然而，在有先前 EHE 诊断的情况下，CAMTA1 可以作为诊断标志物；尤其是在有限的细胞学材料上。进一步的研究将有助于支持我们的结果。
