Hemangioendothelioma: a rare case of a primary intracardiac tumor

Kaposiform hemangioendothelioma of the heart: a case report and literature review

Kaposiform hemangioendothelioma is a rare tumour of vascular origin that rarely occurs in the heart. We provided a rare case of a 26-day-old infant with tachypnoea. Echocardiography showed a solid tumour in the pericardial cavity and a large amount of pericardial effusion. The solid tumour was confirmed by surgery, and the pathology was kaposiform hemangioendothelioma. We analysed this case and reviewed the related literature to explore the clinical features and echocardiographic manifestations to improve the understanding, diagnosis, and treatment of this disease for clinicians and sonographers.

Vascular tumors of the mediastinum

Vascular tumors represent only a sliver of all tumors affecting the mediastinum, but they pose diagnostic challenges due to significant overlap among entities, ever-evolving classification schemes, and the exquisite rarity of some of the entities not only in the mediastinum but in pathology practice as a whole. Most of the vascular tumors are better known to the practice of soft tissue pathology, from which some of the knowledge of clinical behavior can be extrapolated. For example, the stratification of epithelioid hemangioendothelioma (EHE) into two biologically separate categories has effectively translated from the somatic soft tissues to the thorax. For other entities, the effective validation of soft tissue parameters is hindered by the small numbers of reported mediastinal cases. Many of the treatment modalities have also transferred over, with the key differences resting on the difficulty in achieving complete surgical resection for mediastinal tumors as opposed to those in the somatic soft tissues. Accordingly, systemic drug therapies have emerged as attractive options for some of the mediastinal vascular tumors, such as kaposiform hemangioendothelioma (KHE) and Kaposi sarcoma (KS). The categories presented herein mirror the classification scheme set forth by the 5th Edition WHO Classification of Soft Tissue and Bone Tumors. This review focuses on the biologically aggressive vascular neoplasms while limiting discussion of the benign entities to relevant comparisons in the differential diagnoses. While distinguishing among the benign entities has academic importance, in practice, the stakes are far higher for diagnosing the biologically aggressive tumors given their marked heterogeneity in clinical outcomes. Practical advice for problem areas in pathology will be reviewed alongside tumor pathobiology, including the latest in molecular diagnostics.

First Intracardiac Kaposiform Hemangioendothelioma in an Infant Resolved With Sirolimus: A Case Report

INTRODUCTION

Kaposiform hemangioendothelioma (KHE) is a rare and aggressive vascular tumor that can be associated with a consumptive coagulopathy and thrombocytopenia (Kasabach-Merritt phenomenon). Only one case of an intracardiac KHE has been reported which was treated with surgical excision and then expectant management.

CASE PRESENTATION

We present a patient with an intracardiac KHE which presented as a large mass surrounding the atria, pulmonary veins, superior vena cava, and infiltrating the atrial septum with moderate compression of the superior vena cava and mild compression of the pulmonary veins. This tumor clinically presented as persistent tachypnea and was unresponsive to conventional therapy with vincristine and steroids but responded dramatically to Sirolimus with almost complete regression on follow-up.

CONCLUSIONS

None of the current treatments for KHE, alone or in combination therapy have been found to be effective in a uniform or reproducible manner. Well designed, preferably randomized trials are required for a better understanding of the appropriate dosage and duration as well as response to treatment and a consensus of first and second line therapies.

Infantile cardiac vascular tumour: from prenatal diagnosis to postnatal treatment

Primary vascular tumour of the heart is rare, especially in neonates and infants. We report a male premature newborn with a right atrial tumour associated with a large amount of pericardial effusion detected by screening foetal echography. Diagnosis of capillary haemangioma was confirmed by histopathological examination after complete surgical resection. Other vascular tumours in the neonates and infants reported in the English literatures are reviewed, and one algorithm for both prenatal and postnatal management is proposed.