Intrasinusoidal Spread of Hepatic Epithelioid Hemangioendothelioma: Implications for the Diagnosis in Minimal Samples

CAMTA1-immunonegative epithelioid hemangioendotheliomas of the liver: a clinicopathological and molecular analysis of seven cases

Background

Epithelioid hemangioendothelioma (EHE) is a rare malignant vascular tumor. Most EHEs (>90%) cases harbor WWTR1::CAMTA1 fusion gene, and CAMTA1 immunohistochemistry (IHC) is a highly sensitive and specific tool for EHE diagnosis. However, there exist CAMTA1-immunonegative cases, the majority of which harbor YAP1::TFE3 fusion, with a few cases having more rare fusions. Liver is one of the most common sites of EHE, where the CAMTA1 subtype dominates, and the other variants are extremely rare. Hence, we focused on the hepatic CAMTA1-immunonegative EHEs to analyze the clinicopathological and molecular features of these peculiar cases.

Methods

The SNOMED search of the hospital pathology files between January 2016 to November 2023 identified 57 hepatic EHEs and 7 cases were CAMTA1-immunonegative. Fluorescence in situ hybridization (FISH), next generation sequencing (NGS) and Sanger sequencing were performed to identify the genetic change of the 7 cases.

Results

This series included 3 females and 4 males, aged from 33 to 64 years. All the 7 cases were negative for CAMTA1 IHC. Four cases were positive for TFE3 IHC and exhibited YAP1::TFE3 fusion. Another 3 cases were also negative for TFE3, while WWTR1::CAMTA1 fusion were detected by NGS in 1 case and demonstrated by FISH in all the 3 cases. Morphologically, among the 4 TFE3 rearrangement cases, 3 cases showed the TFE3-sutype morphologic appearance, while the histology of 1 case was similar to that of CAMTA1- subtype. In the 3 CAMTA1-rearranged lesions, 2 cases had classic EHE morphology, and 1 case exhibited atypical histology, with higher atypia and well-formed vessels. Surgical resection was performed on five cases and two cases were biopsied and received chemotherapy. Follow-up information was available in 6 patients (median 46 months), including 4 patients were alive without disease and 2 patients were alive with disease.

Conclusion

Our study reported 7 CAMTA1-immunonegative hepatic EHEs and most of them were TFE3-rearranged EHEs with morphology variation. Moreover, there does exist the CAMTA1-immunonegative but CAMTA1-rearranged EHE cases. Therefore, the diagnosis of EHE should be based on morphology, combined with CAMTA1 and TFE3 IHC, and if necessary, supplemented by genetic analysis including FISH and NGS, to establish correct diagnosis.

Clinical, Histopathological, and Immunophenotypic Spectrum of Hepatic Epithelioid Hemangioendothelioma: Eight Years' Data of a Tertiary Care Center from North India

Background/Aims

Epithelioid hemangioendothelioma (EHE) is an uncommon vascular tumor that commonly affects the liver. Hepatic EHE (HEHE) presents with variable clinical and histopathological features. We describe detailed clinico-histopathological features, differential diagnosis, and treatment outcomes of the cases of HEHE diagnosed in our center.

Methods

All cases of HEHE diagnosed in our institute in the last eight years (2016-2023) were reviewed (n = 8; 11 samples) (total 36 cases of EHE; 22.2%). The clinical features, radiology, histopathology, immunophenotype, molecular features, and treatment outcomes of all cases were evaluated.

Results

The median age of presentation was 49.5 years with a female: male ratio of 7:1. Abdominal pain was the commonest presentation. Approximately two-thirds of the patients had multifocal lesions. Histopathology showed purely epithelioid, predominantly epithelioid, and predominantly spindle-cell morphology in 50%, 25%, and 25%, respectively. All cases showed typical myxohyaline/fibrous stroma and organized thrombi of the portal/central veins. CD31 was the most commonly used immunostain with positivity in all cases. CAMTA1 break-apart fluorescence in situ hybridization was positive in 75% of cases, while none showed TFE3 immunopositivity. Chemotherapy was the most commonly employed therapy (n = 5) followed by surgery (n = 2). The median duration of follow-up was 26 months. Five patients were alive with disease (two patients ≥3 years), one patient died of sudden cardiac death, and two patients were lost to follow-up. Two patients developed metastatic disease at follow-up.

Conclusions

We describe the clinico-histopathological features and differential diagnosis of HEHE. This appears to be the largest case series of HEHE from India.

Three cases of hepatic epithelioid hemangioendothelioma evaluated using conventional and contrast-enhanced ultrasound: Case reports

Hepatic epithelioid hemangioendothelioma (HEHE) is a very rare vascular endothelial cell tumor, which lacks typical clinical manifestations and specificity of imaging features. Whether the background of fatty liver and the difference in Contrast enhanced ultrasound (CEUS) characteristics between large and small lesions has not been well defined. In this case reports, we described the ultrasound image features of three patients with HEHE. These three patients with HEHE have certain similar characteristics of conventional ultrasound and CEUS. CEUS imaging features include large nodules show earlier perfusion than liver parenchyma, with rim-enhancement, nonenhancing regions in the center, while small nodules show earlier perfusion than liver parenchyma, with hyperenhancement. All nodules show faster washout than hepatic parenchyma, showing heterogeneous hypoenhancement, and more washout lesions can be found in the PVP and LP. Conventional ultrasound and CEUS not only help to improve the diagnostic confidence of HEHE of rare liver tumors, but also can guide the biopsy area, making it easier to make accurate pathological diagnosis.

Sinusoidal Growth Pattern of Hepatic Melanoma Metastasis: Implications for Histopathologic Diagnosis

Metastatic tumors interface with liver in multiple patterns, of which, the rare "sinusoidal" growth pattern can be subtle and easily overlooked on biopsy. We sought to characterize the metastasis-to-liver interface patterns of melanoma compared with other tumor types and assess the incidence of metastatic melanoma in histologically normal-appearing targeted liver lesion biopsies. Liver lesion samples from 54 melanoma patients were assessed. Nearly normal-appearing cases, defined as no obvious malignancy on routine hematoxylin and eosin stain (n=24), were stained with SOX10 and confirmed with MelanA. Tumor-to-liver interface patterns were determined in biopsies overtly positive for metastatic melanoma (n=30) versus other hepatic metastases as controls (colon, n=28; breast, n=20; pancreaticobiliary, n=20; and neuroendocrine, n=28). Of the 24 nearly normal-appearing liver biopsies from melanoma patients, 3 had subtle melanoma cells detected in sinusoids, confirmed with immunohistochemistry. Of 30 livers overtly positive for melanoma, 8 showed the sinusoidal pattern, compared with none in other metastases. In total, 11/33 (33%) cases of metastatic melanoma liver biopsies demonstrated the sinusoidal pattern. We describe 11 metastatic melanoma cases in liver with the rare sinusoidal pattern, 3 of which were subtle and easy to miss on routine hematoxylin and eosin stain. Given that sinusoidal metastasis does not elicit a tissue reaction, it is prudent for the pathologists to be aware of this pattern of metastases and have a low threshold to order immunostains for accurate diagnosis and optimal patient care.

Laparoscopic resection of hepatic epithelioid hemangioendothelioma: report of eleven rare cases and literature review

BACKGROUND

Hepatic epithelioid hemangioendothelioma (HEHE) is an extremely rare borderline tumor of vascular endothelial origin. Laparoscopic resection of HEHE has never been reported.

METHODS

The clinical data of eleven patients with HEHE (4 women and 7 men) who were diagnosed and treated at the Union Hospital (Wuhan, China), and Wuhan Asia General Hospital (Wuhan, China), between March 2012 and July 2020 were analyzed retrospectively.

RESULTS

The mean age of HEHE patients was 42.4 ± 13.9 years (range 22-67 years). All patients underwent laparoscopic surgery alone or in combination with radiofrequency ablation. Most tumors showed aggressive growth or metastasis. By immunohistochemistry, tumor cells were positive for CD31, CD34, ERG, PCK, FLi-1, TFE-3, and Ki-67 (labeling index range, 5-15%). In one of the patients, the tumor was accompanied by partial necrosis with a local appearance of epithelioid angiosarcoma. Postoperative adjuvant treatment included chemotherapy, sorafenib, and Huaier granule. As of July 2020, the median follow-up duration was 36 months (range, 9-60 months), with 2 (18.2%) patients experiencing tumor recurrence.

CONCLUSIONS

This is the first report of laparoscopic hepatectomy of HEHE. Curative laparoscopic hepatectomy might be an acceptable treatment for appropriate HEHE patients.

Laparoscopic repeat liver resection for hepatic epithelioid hemangioendothelioma

BACKGROUND

Optimal treatment for patients with hepatic epithelioid hemangioendothelioma (HEHE) remains unclear. Laparoscopic repeat liver resection (LR) is a minimally invasive and potentially effective surgical option for multiple HEHEs.

CASE PRESENTATION

A 42-year-old woman with no relevant history was admitted for multiple liver tumors. Six tumors were observed on T2-weighted magnetic resonance imaging (MRI) including one in S2, two in S3, two in S7, and one in S8. Pathological evaluation of percutaneous tumor biopsy tissue suggested a diagnosis of HEHE and laparoscopic LR was planned. The procedure began with partial resection of S7 and partial resection of S8 and left lateral sectionectomy were performed. Another tumor was found intraoperatively on the surface of S6, necessitating removal by partial resection. Pathological evaluation of the resected tumor tissue from all seven tumors concurred with that of the preoperative biopsy. The patient was discharged on postoperative day 6 without any complications. A follow-up MRI 15 months after the primary surgery revealed one tumor each in S4, S6, and S8. Laparoscopic repeat LR was performed. The patient was discharged on postoperative day 5 without any complications. All three recurrent tumors were pathologically confirmed as HEHEs.

CONCLUSIONS

We successfully treated primary and recurrent HEHEs with laparoscopic LR, which is a reasonable minimally invasive procedure considering the possibility of multiple courses of liver surgery in patients with HEHE.

Aberrant keratin expression is common in primary hepatic malignant vascular tumors: A potential diagnostic pitfall

Malignant vascular neoplasms such as epithelioid hemangioendothelioma (EHE) and angiosarcoma (AS) can arise within the liver. The aim of this study was to study the expression of keratins CK7, AE1/AE3 and OSCAR in primary hepatic EHE and AS. 9 cases of hepatic EHE and 13 cases of hepatic AS were stained with ERG, CK7, keratin AE1/AE3 and keratin OSCAR. Their expression was graded as 1+ (1-25% of tumor cells positive), 2+ (26-50%), 3+ (51-75%) or 4+ (>75%). ERG was positive in all 9 (100%) EHEs and all 13 (100%) ASs. CK7 was positive in 5/9 (56%) EHEs (2, 1+; 1, 2+; 1, 3+; 1, 4+) and 1/13 (8%) AS (2+). Keratin OSCAR was positive in 6/9 (67%) EHEs (5, 1+; 1, 2+) and 4/13 (31%) ASs (2, 1+; 1, 2+; 1, 4+). Keratin AE1/AE3 was positive in 6/9 (67%) EHEs (3, 1+; 3; 2+) and 4/13 (31%) ASs (2, 1+; 1, 2+; 1, 4+). Overall, 6/ 9 (67%) EHEs were positive for at least one keratin marker, of which 5 were positive for all 3 keratins (AE1/AE3, OSCAR and CK7) while 1 was positive only for 2 keratins (OSCAR and AE1/AE3). 4/13 (31%) of ASs were positive for both keratins OSCAR and AE1/AE3, of which 1 case was also positive for CK7. Aberrant keratin expression is common in primary hepatic EHEs (67%) and ASs (31%). Awareness of this diagnostic pitfall is important for avoiding misdiagnosis of these primary hepatic malignant vascular tumors as carcinomas.