[Refractory kaposiform hemangioendothelioma with Kasabach-Merritt syndrome: clinical analysis of 10 cases].

Objective: To analyze the clinical value of sirolimus plus prednisone for the treatment of the refractory kaposiform hemangioendothelioma(RKHE) and Kasabach-Merritt syndrome(KMS). Method: Clinical retrospective analysis was carried out for 10 patients recruited in Children's Hospital Affiliated to Capital Institute of Paediatrics from January 2014 to January 2017 who were non responders to or relapsers after the treatment of propranolol, prednisone, pingyangmycin and lauromacrogol(5 cases RKHE, 5 cases RKHE plus KMS, age ranged from 6 days to 9 years); patients were treated with sirolimus at the dosage of 0.035 ml/(kg·d), once a day, for 6-410 days; the diagnosis of 10 patients were confirmed by pathological biopsy and immunohistochemical examination(IHC); the difference of the coagulation parameters and the platelet counts, the size of tumor and ecchymosis at different stages of treatment were recorded and measured by scale and ultrasonography; the side effects of sirolimus were recorded as well. Result: Clinical characteristics of 10 cases (6 male and 4 female) RKHE with KMS were refractory dark red hard hemangioma or ecchymosis, the platelet counts were lower than 30.0×10(9)/L, (15±7)×10(9)/L, coagulation tests were obviously abnormal, fibrinogens were significantly decreased(0.8±0.5)g/L, the fibrin lysates and D-dimer were significantly increased(100±23)mg/L, (10 000±2 200)ng/L, the prothrombin time and activated partial thromboplastin time were prolonged(25.0±2.1)s, (58.0±3.4)s. The pathologic characteristics of the tumors were similar: spindle tumor cells, mass distribution and deeply stained nuclei tumor cells. IHC revealed positive staining for D2-40, CD31 and CD34. Stainings for factor Ⅷ and GLUT-1 were negative. In five cases RKHE plus KMS were treated with sirolimus and prednisone, after (6.5±0.7) days treatment, the platelet counts were obviously increased(72.0±0.6)×10(9)/L, coagulation parameters were obviously improved, fibrinogen significantly increased(1.5±0.2)g/L, the fibrinlysates and D-dimer significantly decreased(7±3)mg/L, (2 300±200)ng/L, the prothrombin time and activated partial thromboplastin time were prolonged(15±2.3)s, (42±3.4) s, and the sizes of tumor and ecchymosis were slightly shrunken 18%±3%, 38%±5%; after (30±5.7) days treatment, the platelet counts and coagulation parameters returned to normal(146±36)×10(9)/L, and the size of tumor and ecchymosis were obviously shrunken 73%±3%, 97%±3%; after (3±0.4) months treatment, the tumor was obviously shrunken by 93%±2% and no longer palpable. In five cases with RKHE without KMS manifested stubborn dark red hard hemangiomatous plaques, coagulation tests and platelet were obviously normal, these patients were treated with sirolimus, after (2.0±0.6) months treatment, the tumor became shrunken 8%±3%, with continuous treatment the tumor shrunk gradually, after (4.0±3.2)months(2-18 mouths) the tumor was not eliminated 51%±7%. Conclusion: RKHE and KMS have typical clinical, laboratory and pathological characteristics, sirolimus plus prednisone have remarkable efficacy and minor side effects, it should be recommended for the treatment of KHE with KMS.