Treatment of Corticosteroid-Resistant Vascular Tumors Associated with the Kasabach-Merritt Phenomenon in Infants: An Approach with Transcatheter Arterial Embolization Plus Vincristine Therapy

Purpose: To investigate the effectiveness and application of transcatheter arterial embolization (TAE) plus systemic vincristine for treatment of corticosteroid-resistant vascular tumors associated with Kasabach-Merritt phenomenon in infants. Materials and Methods: TAE was performed in 17 infants (average age, 4.3 mo +/- 2.4; range, 1-10 mo) with corticosteroid-resistant vascular tumors associated with Kasabach-Merritt phenomenon, followed by intravenous vincristine once weekly for systemic chemotherapy. The effects and complications were observed and evaluated after a cycle (1 cycle: TAE plus treatment with vincristine every 4 weeks). Cycles were repeated in infants with platelet counts < 150 x 10(9)/L. Results: In 17 patients, 36 treatment cycles were successfully performed. The platelet count for all patients increased to >= 100 x 10(9)/L for the first time at 6.0 days +/- 3.5; the platelet level of 15 infants was maintained at levels > 150 x 10(9)/L at 57.5 days +/- 16.5. Before treatment, two infants had a normal fibrinogen level (2.21 g/L and 2.34 g/L); the fibrinogen level in the other 15 infants was first found to be increased to >= 2.0 g/L at 7.0 days +/- 3.4 and was stabilized at levels > 2.0 g/L at 55.9 days +/- 13.8 after treatment. Complications were graded as major in four eases and as minor in 13 cases. Conclusions: TAE plus vincristine can rapidly improve levels of platelets and fibrinogen, and it is an effective method for treatment of corticosteroid-resistant vascular tumors associated with Kasabach-Merritt phenomenon in infants.