Kaposiform haemangioendothelioma in an adult: lack of response to topical sirolimus and response to radiotherapy.

Kaposiform haemangioendothelioma (KHE) is a rare, primarily paediatric tumour with only a handful of case reports in the adult population. Given the paucity of evidence, this article is important in raising awareness of radiotherapy as a suitable and effective treatment in the adult population with KHE and highlights the potential limitations of topical sirolimus in these tumours.

Successful low-dose radiotherapy treatment for Kasabach-Merritt syndrome.

Kasabach-Merritt syndrome (KMS) is characterized by hemangioma associated with life-threatening thrombocytopenia, and is a consumptive coagulopathy. Although treatments available include corticosteroids, α-interferon, vincristine, and surgery, response may be unsatisfactory, and the mortality rate remains at approximately 30%. Although radiotherapy has been used effectively for KMS, it may cause growth retardation and secondary malignancy. We report a case of KMS in which hemangioma of the left thigh was successfully treated with low-dose radiotherapy (6 Gy in six fractions, weekly) after failure of corticosteroid therapy. No significant late effects due to the radiotherapy were noted at 5 year follow up. Thus, low-dose radiotherapy remains an important treatment method for KMS when patients fail to respond to other treatments.

Kasabach-Merritt phenomenon in an adult man with a tufted angioma and cirrhosis responding to radiation, bevacizumab, and prednisone.

BACKGROUND: Tufted angioma (TA) is a benign cutaneous vascular tumor that most commonly occurs in young children. TAs have rarely been reported in adults and/or arising within port-wine stains (PWS). Kasabach-Merritt phenomenon (KMP) is a life-threatening consumptive coagulopathy hypothesized to occur specifically in young children who develop either a TA or kaposiform hemangioendothelioma. METHODS: Here we present a 52-year-old man with hepatitis C cirrhosis who presented with an extensive, painful vascular tumor involving the right side of his head, neck, and back that initially arose within a PWS. RESULTS: He developed petechiae, severe thrombocytopenia, and a consumptive coagulopathy consistent with KMP. An incisional biopsy of his vascular tumor was compatible with a TA. Numerous treatments aimed at halting proliferation of his TA were attempted, with sustained improvement in his vascular tumor and platelet count achieved only after several courses of electron beam radiation therapy in association with corticosteroids and bevacizumab. CONCLUSION: To our knowledge, this represents the first report of KMP in an adult man associated with TA and challenges previous hypotheses arguing that KMP occurs only in children. We offer our own hypothesis concerning how, in extremely rare circumstances, this life-threatening consumptive coagulopathy may occur in adults. Electron beam radiation therapy in association with corticosteroids can be an effective treatment in these rare patients.

Congenital kaposiform hemangioendothelioma with Kasabach-Merritt phenomenon successfully treated with low-dose radiation therapy.

Kaposiform hemangioendothelioma (KHE) associated with Kasabach-Merritt phenomenon is a life-threatening vasculopathy. The current mainstay treatment for KHEs is corticosteroids and chemotherapy, but these medications do not work for all patients and carry significant side effects. We report a neonate with a large congenital KHE who responded extremely well to low-dose radiation therapy.