Noninvoluting congenital hemangioma (NICH) is a distinct vascular tumor of infancy.

We describe the clinical characteristics, histopathology, imaging, and natural history of NICH and compare our findings with previous reports.

We conducted a retrospective review of charts and photographic databases from 2 vascular anomaly centers over a 15-year period.

Thirty cases of NICH were identified. All patients had fully formed vascular lesions at birth that demonstrated a nonprogressive course. The trunk and lower extremities were preferred sites and there was a female predominance. Thirteen of 30 patients reported pain. Focal necrosis and scarring was seen in a minority. Doppler studies, when performed, confirmed high vascular flow. Microscopic evaluation of 4 excised lesions showed lobular areas of endothelial cell proliferation directly adjacent to ectatic malformed vessels. Immunohistochemical studies demonstrated absence of glucose transporter-1 protein expression in every case. Wilms tumor–1 positivity was observed in lobular areas. The larger vessels did not stain with Wilms tumor–1, but some displayed D2-40 positivity.

Patients were referred to university-based pediatric vascular anomaly centers, with potential bias toward more severe or extensive cases.

This retrospective study highlights the unique clinical and histopathologic features of NICH.