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.