Clinical characterization and long-term outcomes in pediatric epithelioid hemangioendothelioma

Advanced epithelioid haemangioendothelioma in a child presenting as deep vein thrombosis

Venous thromboembolism (VTE) is a rare event in children and does not usually trigger investigation for malignancy. We report the case of a previously healthy female teenager presenting with unilateral leg swelling. Colour-Doppler ultrasound confirmed deep vein thrombosis (DVT), and the thrombophilia workup was negative. Cross-sectional imaging identified multiple liver and lung lesions, diagnosed as epithelioid haemangioendothelioma (EHE) at biopsy. Lifelong anticoagulation was commenced; the patient was initially observed and then started on sirolimus at disease progression. We describe the first published case of EHE presenting with DVT in a child. Clinicians need to be mindful of the association between cancer and thrombosis, even in paediatric patients.

The challenges of hepatic epithelioid hemangioendothelioma: the diagnosis and current treatments of a problematic tumor

BACKGROUND

Hepatic epithelioid hemangioendothelioma (HEHE) is a malignant vascular tumor known for its rarity. The different types of this hepatic tumor (single, multiple-nodular or diffused) indicate different prognosis and treatment plans. However, the heterogenic clinical manifestation creates a dilemma and a wide range of challenges when attending to HEHE patients. This review addresses the unique profile and clinical challenges that complicate the diagnosis and treatment of HEHE while focusing on current therapeutic strategies and their limitations.

MAIN TEXT

The unclear etiology is a challenging feature of HEHE. The exact involvement of potential risk factors and mechanism of development are still undefined. Relevant genetic alterations like WWTR1-CAMTA1 fusion have been investigated; however, they are only applicable as diagnostic markers and their influence on therapeutic efficacy is largely unknown. Other characteristics include asymptomatic manifestation, lack of unique hepatic functional alterations, high rates of misdiagnosis and late-stage identification when metastases already exist. Currently, tissue biopsy is the main tool to establish a definite diagnosis but is challenged with the limited awareness to suspect HEHE at early stages and the lack of relevant guidelines due to the rarity and the insufficiency of relevant research. The absence of treatment guidelines is the greatest challenge of HEHE. Generally, Surgical approaches are recommended due to the benefits of prolonged survival and enhanced prognosis. Nonetheless, only a minority of patients are eligible for resections while liver transplants are faced with severe insufficiency of donor organs and long wait-lists. On the other hand, a variety of non-surgical treatments (like anti-angiogenic agents, interferon alpha-2B and sirolimus) are presented with a promising potential. However, relevant studies are challenged with limited sample-sizes and lack of prospective designs.

CONCLUSION

Regardless to decades passing since its discovery, HEHE still creates a dilemma due to its challenging clinical profile and lack of treatment guidelines. Raising awareness of HEHE in clinical practices improves the ability to diagnose this rare tumor at early stages and develop stronger research strategies and treatment guidelines to regulate the medical care provided to HEHE patients.

Penile Epithelioid Hemangioendothelioma in a Child

An 8-year-old boy initially thought to have a penile arteriovenous malformation was later diagnosed with a rare vascular sarcoma, epithelioid hemangioendothelioma (EHE). Despite challenges in diagnosis, he underwent supraselective angioembolization and partial penectomy for oncological clearance. EHE, a low-grade malignancy, requires prompt identification and treatment due to potential systemic involvement.

The patient perspective on sirolimus for epithelioid hemangioendothelioma (EHE): results of a community survey highlighting the importance of equitable access to treatments

Background

Epithelioid hemangioendothelioma (EHE) is an ultra-rare, vascular sarcoma with clinical presentation ranging from an indolent to an aggressive form. Over 50% of patients present with metastatic disease, requiring systemic therapy, although no systemic therapies are specifically approved for EHE. Retrospective evidence supports the activity of mTOR inhibitors (e.g. sirolimus), although available only off-label. EHE patients and advocates are therefore working to support approval of effective treatments by collecting data on patient perspectives and experiences.

Materials and methods

In February 2023, the EHE Rare Cancer Charity (UK) and The EHE Foundation (US), with other advocates, conducted a survey of perspectives and experiences of EHE patients regarding the use and accessibility of sirolimus. The survey consisted of 20 questions designed for individuals undergoing treatment, those who had been treated, or had never been treated with the drug. Widely promoted within the patient community, the online survey categorized patients into three cohorts for the analysis: liver transplant patients, non-transplant patients who had ever taken sirolimus and sirolimus-naïve non-transplant patients.

Results

The survey evaluated data from 129 patient responses from 21 countries, mostly from USA, UK, Australia, and Canada (70%). The liver transplant, sirolimus and non-sirolimus cohorts were 16%, 25% and 59%, respectively. In the sirolimus group 66% reported treatment durations exceeding one year, with 16% exceeding five years, indicating the drug's efficacy. In the non-sirolimus group, the drug was not available for 42% and for 11% sirolimus was available but not selected for treatment because of its off-label status. Overall, 87% of all patients across all cohorts expressed the importance of the drug's availability as hugely or very important.

Conclusion

The survey responses highlight the activity of sirolimus for EHE and the importance of securing a label extension for the drug delivering equitable access to this treatment for patients.

Update on the Pathology of Pediatric Liver Tumors: A Pictorial Review

Liver tumors in children are uncommon and show remarkable morphologic heterogeneity. Pediatric tumors may arise from either the epithelial or mesenchymal component of the liver and rarely may also show both lines of differentiation. Both benign and malignant liver tumors have been reported in children. The most common pediatric liver tumors by age are benign hepatic infantile hemangiomas in neonates and infants, malignant hepatoblastoma in infants and toddlers, and malignant hepatocellular carcinoma in teenagers. Here, we provide an up-to-date review of pediatric liver tumors. We discuss the clinical presentation, imaging findings, pathology, and relevant molecular features that can help in the correct identification of these tumors, which is important in managing these children.

Prognostic Factors in Epithelioid Hemangioendothelioma: Analysis of a Nationwide Molecularly/Immunohistochemically Confirmed Cohort of 57 Cases

Epithelioid hemangioendothelioma (EHE) is an extremely rare vascular sarcoma with variable aggressive clinical behavior. In this retrospective study, we aimed to investigate prognostic factors based on clinicopathologic findings in a molecularly/immunohistochemically confirmed nationwide multicenter cohort of 57 EHE cases. Patients had unifocal disease (n = 29), multifocal disease (n = 5), lymph node metastasis (n = 8) and/or distant metastasis (n = 15) at the time of diagnosis. The overall survival rate was 71.4% at 1 year and 50.7% at 5 years. Survival did not correlate with sex, age or histopathological parameters. No survival differences were observed between multifocal and metastatic disease, suggesting that multifocality represents early metastases and treatment options are limited in comparison to unifocal disease. In unifocal tumors, survival could be predicted using the risk stratification model of Shibayama et al., dividing the cases into low- (n = 4), intermediate- (n = 15) and high- (n = 3) risk groups. No clinical or histopathological parameters were associated with progressive unifocal disease course. Lymph node metastases at the time of diagnosis occurred in 14.0% of the cases and were mainly associated with tumor localization in the head and neck area, proposing lymph node dissection. In conclusion, our results demonstrate the aggressive behavior of EHE, emphasize the prognostic value of a previously described risk stratification model and may provide new insights regarding tumor focality, therapeutic strategies and prognosis.

Updated information regarding management of hepatic epithelioid hemangioendothelioma

Hepatic epithelioid hemangioendothelioma (HEHE) is a rare hepatic vascular tumor with a borderline biological behavior between hemangioma and hemangiosarcoma. It tends to be multiple or diffuse subcapsular lesions across the liver but has no characteristic clinical manifestations or imaging findings. On computed tomography and magnetic resonance imaging, these lesions usually have a hypodense appearance with heterogeneous enhancement and a "halo sign" or "lollipop sign" may be evident in some cases. HEHE is diagnosed mainly based on a pathological examination along with differential immunohistochemical markers such as CAMTA1, CD31, CD34, CD10, vimentin, and factor VIII antigen. Currently, there are no standardized treatment guidelines for HEHE, and surgery (curative resection and liver transplantation) remains the mainstay of treatment. Studies have indicated that extra-hepatic metastasis might not be a contraindication for resection or transplantation. Systemic chemotherapeutic agents including doxorubicin, vincristine, interferon-a, 5-fluorouracil, and thalidomide, as well as VEGF-related agents are being investigated, but no agents have been approved for the treatment of HEHE.

Epithelioid Hemangioendothelioma: Incidence, Mortality, Prognostic Factors, and Survival Analysis Using the Surveillance, Epidemiology, and End Results Database

Background

Although epithelioid hemangioendothelioma (EHE) is a rare and aggressive vascular tumor, its demographic characteristics remain unclear. We used the surveillance, epidemiology, and end results (SEER) database to determine the clinical features, incidence, and prognostic factors associated with overall survival in patients with EHE.

Methods

The demographic and clinical data of patients with EHE were extracted from the SEER database (1975-2019) to calculate the incidence of EHE and survival rate in these patients. The Cox proportional hazards model and Kaplan-Meier method were used to analyze the prognostic factors of overall survival in these patients. A nomogram and time-dependent receiver operating characteristic (ROC) curve were employed to predict the 3- and 5-year survival rate.

Results

The overall incidence rate (IR) of EHE was 0.230 (95%confidence interval [CI] = 0.201–0.263) per 1,000,000 person-years. According to the age-stratified IR, the highest age-adjusted IR was observed in patients aged 60–79 years (0.524 per 1,000,000 person-years, 95%CI = 0.406–0.665). The majority (30.8%) of the tumors were located in the soft tissue and skin, followed by lesions in the abdomen (28%), respiratory system (19%), bone and joint (8.6%), and others. The 5-year overall survival rate was 55.6% (95%CI = 32.8–73.5%). Multiple Cox regression analysis revealed that age >80 years (hazard ratio [HR] = 8.57, 95%CI = 2.32–31.63, P < 0.001), African-American race (HR = 2.52, 95%CI = 1.31–4.85, P < 0.01), “American Indian/Alaska Native” or “Asian or Pacific Islander” (HR = 2.99, 95%CI = 1.5–5.96, P < 0.01) race, and respiratory tumors (HR = 2.55, 95%CI = 1.37–4.75, P < 0.01) were distinctly related to worse overall survival. The calibration plots demonstrated good consistency between nomogram-predicted and actual survival. The area under the time-dependent ROC curve was 0.721 (95%CI = 0.63–0.81) and 0.719 (95%CI = 0.63–0.81) for the 3- and 5-year survival, respectively. For the convenience of researchers and clinicians, we designed an online dynamics nomogram to predict the survival rate.

Conclusion

EHE is a relatively rare vascular tumor, which principally occurs in the soft tissue and skin. It most commonly occurs in patients aged 60–79 years and its incidence has increased in recent years. Age at diagnosis, race, and tumor location may affect the overall survival outcomes.

Ovarian Epithelioid Hemangioendothelioma in a Pediatric Patient: A Case Report

We present a case of an eight-month-old girl who was brought to the emergency department with bloody stools. An initial ultrasound reported a mass in the left iliac fossa that was further characterized by magnetic resonance imaging (MRI) as a hypervascular ovarian tumor. Prior to surgical resection of the tumor, abdominal arteriography with selective embolization and vessel occlusion was performed. Pathology reported epithelioid hemangioendothelioma of the left ovary. This condition has not been previously reported in girls. In this case report, we describe the ultrasound, MRI, and arteriographic findings with a histopathologic correlation of an adnexal tumor that is unknown in the pediatric female population until now.

Pediatric vascular tumors of the liver: Review from the pathologist’s point of view

Differential diagnosis of pediatric vascular liver tumors can be challenging due to inconsistent nomenclature, histologic overlap and the rarity of some entities. Here we give an up-to-date overview of the most important entities. We discuss the clinic, histology and pathophysiology of hepatic congenital and infantile heman gioma, hepatic epithelioid hemangioendothelioma and hepatic angiosarcoma.

Primary malignant vascular tumors of the liver in children: Angiosarcoma and epithelioid hemangioendothelioma

Primary malignant vascular neoplasms of the liver, angiosarcoma and epithelioid hemangioendothelioma, are extremely rare entities in the pediatric population. International Society for the Study of Vascular Anomalies classification system is recommended for the pathologic diagnosis of hepatic vascular lesions in this age group. In this article, we highlight the clinicopathologic characteristics of hepatic angiosarcoma and epithelioid hemangioendothelioma in the pediatric population. Hepatic angiosarcoma in children shows a slight female predominance with an average age of 40 mo at diagnosis. The distinct histologic features include whorls of atypical spindled cells and eosinophilic globules, in addition to the general findings of angiosarcoma. Histologic diagnosis of pediatric hepatic angiosarcoma is not always straightforward, and the diagnostic challenges are discussed in the article. Hepatic epithelioid hemangioendothelioma also demonstrates a female predominance, but is more commonly identified in adolescents (median age at diagnosis: 12 years). Histologically, the lesion is characterized by epithelioid cells and occasional intracytoplasmic lumina with a background of fibromyxoid stroma. While WWTR1-CAMTA1 and YAP1-TFE3 fusions have been associated with epithelioid hemangioendothelioma, there are currently no known signature genetic alterations seen in pediatric hepatic angiosarcoma. Advancement in molecular pathology, particularly for pediatric hepatic angiosarcoma, is necessary for a better understanding of the disease biology, diagnosis, and development of targeted therapies.

Systemic therapies in advanced epithelioid haemangioendothelioma: A retrospective international case series from the World Sarcoma Network and a review of literature

Background

This observational, retrospective effort across Europe, US, Australia, and Asia aimed to assess the activity of systemic therapies in EHE, an ultra‐rare sarcoma, marked by WWTR1‐CAMTA1 or YAP1‐TFE3 fusions.

Methods

Twenty sarcoma reference centres contributed data. Patients with advanced EHE diagnosed from 2000 onwards and treated with systemic therapies, were selected. Local pathologic review and molecular confirmation were required. Radiological response was retrospectively assessed by local investigators according to RECIST. Progression free survival (PFS) and overall survival (OS) were estimated by Kaplan‐Meier method.

Results

Overall, 73 patients were included; 21 had more than one treatment. Thirty‐three patients received anthracyclines regimens, achieving 1 (3%) partial response (PR), 25 (76%) stable disease (SD), 7 (21%) progressive disease (PD). The median (m‐) PFS and m‐OS were 5.5 and 14.3 months respectively. Eleven patients received paclitaxel, achieving 1 (9%) PR, 6 (55%) SD, 4 (36%) PD. The m‐PFS and m‐OS were 2.9 and 18.6 months, respectively. Twelve patients received pazopanib, achieving 3 (25%) SD, 9 (75%) PD. The m‐PFS and m‐OS were.2.9 and 8.5 months, respectively. Fifteen patients received INF‐α 2b, achieving 1 (7%) PR, 11 (73%) SD, 3 (20%) PD. The m‐PFS and m‐OS were 8.9 months and 64.3, respectively. Among 27 patients treated with other regimens, 1 PR (ifosfamide) and 9 SD (5 gemcitabine +docetaxel, 2 oral cyclophosphamide, 2 others) were reported.

Conclusion

Systemic therapies available for advanced sarcomas have limited activity in EHE. The identification of new active compounds, especially for rapidly progressive cases, is acutely needed.