Kaposiform hemangioendothelioma (with Kasabach Merritt syndrome) of the head and neck: case report and review of the literature

Current concepts of vascular anomalies

Vascular anomalies encompass a variety of malformations and tumors that can result in severe morbidity and mortality in both adults and children. Advances have been made in the classification and diagnosis of these anomalies, with the International Society for the Study of Vascular Anomalies establishing a widely recognized classification system. In recent years, notable progress has been made in genetic testing and imaging techniques, enhancing our ability to diagnose these conditions. The increasing sophistication of genetic testing has facilitated the identification of specific genetic mutations that help treatment decisions. Furthermore, imaging techniques such as magnetic resonance imaging and computed tomography have greatly improved our capacity to visualize and detect vascular abnormalities, enabling more accurate diagnoses. When considering reconstructive surgery for facial vascular anomalies, it is important to consider both functional and cosmetic results of the procedure. Therefore, a comprehensive multidisciplinary approach involving specialists from dermatology, radiology, and genetics is often required to ensure effective management of these conditions. Overall, the treatment approach for facial vascular anomalies depends on the type, size, location, and severity of the anomaly. A thorough evaluation by a team of specialists can determine the most appropriate and effective treatment plan.

Kaposiform Hemangioendothelioma: clinicopathological characteristics of 8 cases of a rare vascular tumor and review of literature

BACKGROUND

Kaposiform Hemangioendothelioma (KHE) is a rare vascular tumor of intermediate malignant potential which shows locally aggressive growth but only rarely metastasizes. It is mostly considered to be a tumor of pediatric population but its occurrence in the adults is not uncommon as once considered. Histologically, KHE can mimic other soft tissue neoplasms of different behaviors (e.g. Kaposi Sarcoma, hemangioma) and establishing the correct diagnosis is important for appropriate treatment. Herein, we describe the clinicopathological features of 8 cases of KHE which will be helpful in making their diagnosis.

METHODS

We reviewed pathology reports, microscopy glass slides and obtained follow up information about 8 cases of KHE which were diagnosed at our institution from January 2008 till June 2020. Immunohistochemical stain for HHV8 was also performed.

RESULTS

Age ranged from 7 months to 25 years. Seven patients were less than 20 years of age and one patient was 25 years old. Equal gender distribution was observed. Extremities were the most common sites of involvement, followed by head and neck, pancreas and ischiorectal region. 2 cases were resection specimen and all others were incisional biopsies. The largest tumor size was 5.5 cm in one of the resections. The incisional/fragmented tissues were all less than 5 cm in aggregate. Most cases showed predominance of nodular growth and a minor component of spindle cell population along with lymphangiomatosis like vascular channels, with evidence of microthrombi in 2 cases. Few multinucleated giant cells were observed in 2 cases. None of the cases exhibited significant nuclear atypia or mitotic activity. One of the cases arising in dermis showed underlying bone involvement. HHV8 was negative in 7/7 cases.

CONCLUSIONS

KHE can also involve adult population and it should always be considered in the differential diagnoses of a vascular lesion. Presence of multinucleated giant cells is a rare finding. Knowledge about histological features and potential mimics is helpful in avoiding misdiagnosis.

Pediatric facial kaposiform hemangioendothelioma: a case report and review of the literature

Cutaneous kaposiform hemangioendothelioma (KHE) and tufted angioma (TA) are vascular tumors that are often misdiagnosed. Treatment urgency and type varies depending on which tumor-type is diagnosed, because of the differing rates of progression to Kasabach–Merritt phenomenon. An 11-month-old male presented with a facial mass and biopsy results favoring a diagnosis of TA. The diagnosis of KHE, was later favored over TA given the overall clinical picture of initial rapid growth. However, serial imaging showed no subsequent growth, suggesting that clinically diagnosed KHE, may follow a benign clinical course when biopsy results suggest a diagnosis of TA.

Kaposiform hemangioendothelioma with Kasabach-Merritt phenomenon in an infant: Successful treatment with prednisolone, vincristine, and addition of sirolimus

A full-term newborn with kaposiform hemangioendothelioma (KHE) affecting the right thigh with thrombocytopenia due to Kasabach-Merritt phenomenon (KMP) was referred to our center. After biopsy, he rapidly evolved to severe thrombocytopenia and severe coagulopathy. Standard therapy was initiated with prednisolone and vincristine. His coagulopathy worsened to life-threatening hemorrhage necessitating aggressive blood products replacement. Sirolimus was added; he became transfusion independent with no further bleeding and reduction in tumor size. Addition of sirolimus to treatment of vascular anomalies with hemostatic complications should be considered as part of early treatment for patients with KMP/KHE.

Pediatric Vascular Tumors of the Head and Neck

Oral and maxillofacial surgeons are often involved in the diagnosis and treatment of vascular neoplasms of the head and neck. An incorrect diagnosis may lead to improper or unnecessary treatment. This article reviews the diagnosis and management of vascular tumors.

Kaposiform hemangioendothelioma of paranasal sinus

Kapossiform hemangioendothelioma (KHE) of the paranasal sins (PNS) is a rare cause of recurrent epistaxis. To date, only two cases of PNS KHE have been reported in the literature, both occurring in the pediatric population. The case presented here appears to be the first case of PNS KHE occurring in an adult. A 46-year-old white female presented with progressively worsening unilateral recurrent epistaxis. Diagnostic histopathology confirmed it to be KHE. After a detailed workup, the tumor was completely excised en bloc (medial maxillectomy; anterior and posterior ethmoidectomy) via a lateral-rhinotomy approach. Complete excision of the tumor with clear margins offers the best results.

Paclitaxel-based chemotherapy for aggressive kaposiform hemangioendothelioma of the temporomastoid region: Case report and review of the literature

BACKGROUND

Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor of infancy and childhood. This tumor results in poor prognosis, and therefore, development of a more effective treatment is needed.

METHODS AND RESULTS

We describe an 11-year-old boy presenting with left facial palsy caused by aggressive KHE of the left temporomastoid region. He was treated with paclitaxel-based chemotherapy, because of the difficulty with complete surgical resection for anatomic factor, multiple lung metastases on diagnosis, and no response to conventional treatments. This treatment reduced the volume of primary tumor and lung metastatic lesions, but the efficacy was transitory.

CONCLUSIONS

Paclitaxel-based chemotherapy for aggressive KHE may be effective, therefore the multimodality therapy including paclitaxel of aggressive KHE, particularly in the head and neck, needs to be investigated in further studies.

Soft tissue tumors of the head and neck: imaging-based review of the WHO classification

The World Health Organization (WHO) system for defining and classifying soft tissue tumors is usually applied to lesions that occur in the trunk and extremities, but it also provides an excellent framework for characterizing nonepithelial extraskeletal tumors of the head and neck. Although nonepithelial extraskeletal tumors are in the minority among head and neck lesions, they are by no means rare. The WHO classification system recognizes nine major types based on histologic differentiation: adipocytic, fibroblastic or myofibroblastic, fibrohistiocytic, smooth muscle, skeletal muscle, vascular, pericytic, and chondro-osseous tumors, as well as soft tissue tumors of uncertain differentiation. Tumors of each histologic type may be further subclassified on the basis of their biologic behavior as benign, intermediate (ie, having malignant potential), or malignant. Imaging plays an important role in the noninvasive diagnosis and characterization of nonepithelial soft tissue tumors of the head and neck, providing clues about tumor grade, composition, extent, and involvement of adjacent structures. Although the imaging characteristics of many such tumors are nonspecific, consideration of the clinical history in concert with the imaging findings may help limit the differential diagnosis or even allow reliable diagnosis of some of these tumors.