18F-FDG PET/CT Findings in a Woman With Kaposiform Hemangioendothelioma in the Sacrum

Multivertebral Kaposiform hemangioendothelioma presenting as scoliosis - A case report and review of literature

Kaposiform hemangioendothelioma (KHE) is a rare, locally invasive vascular tumour of childhood that may occur in soft tissue or bones, and is associated with cutaneous plaques and Kasabach-Merritt phenomenon (KMP). We present an instance of a 9-year-old girl with primary vertebral involvement of KHE, whose clinical presentation was with painless, progressive scoliosis alone, sans cutaneous markers. We highlight the imaging features of this rare manifestation and importance of histopathological diagnosis for optimal management.

Case report: A rare case of retroperitoneal kaposiform hemangioendothelioma with spinal involvement without abnormal platelet count in 18F-FDG PET/CT

Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm that mostly appears in infancy or early childhood. Most KHE occurred on the limbs and trunk with cutaneous lesions. Approximately 12% of KHE patients manifested as deep masses and spinal involvement is extremely rare. KHE may develop into life-threatening thrombocytopenia and consumptive coagulopathy, known as the Kasabach-Merritt phenomenon (KMP), especially in patients with retroperitoneal involvement. The thrombocytopenia is usually severe, with a median platelet count of 21 × 10⁹/L at the initial presentation of KMP. Here, firstly we described a case of a 13-month-old girl with KHE who presented the movement limitation of the lower extremity caused by spinal involvement with a normal platelet count. ¹⁸F-fluorodeoxyglucose-positron emission tomography/CT (¹⁸F-FDG PET/CT) showed mildly elevated metabolism in the lesion, suggesting a probably low-grade malignant tumor. Then the patient was diagnosed with KHE by biopsy. After 6-month sirolimus monotherapy, the size of the retroperitoneal lesion was reduced significantly and the patient showed improvement in clinical symptoms. This case demonstrated the advantage of ¹⁸F-FDG PET/CT in the evaluation of disease activity in KHE and the possibility of using ¹⁸F-FDG PET/CT to guide therapy and prognostication.