lesion at the cerebellopontine angle, and spindle cell histologic findings are suggestive of a schwannoma; however, this was ruled out by immunonegative S-100 findings. Infantile hemangioma (IH) was ruled out by the glomeruloid-like architecture of the vascular epithelial nodules, not seen in IH. 1 An additional concern with KHE is the development of KMS. Although KMS has been reported in small (<5 cm) KHEs, it is hypothesized that KMS is more likely with larger retroperitoneal and mediastinal KHEs in younger patients. 1,3 The small size of the KHE at diagnosis may have preempted development of KMS in this patient.Rapid growth and location rendered treatment necessary. Surgical intervention is typically the first-line treatment. Steroids, interferon, and vincristine have been part of the treatment regimen when resection is difficult, as in this case. 2 However, success with these agents has been limited, leading to investigation of other pharmaceuticals. Several studies support the efficacy of sirolimus in reducing tumor size and controlling hematopoietic values. 5 Sirolimus was thus chosen as the initial treatment with good early results.