Infantile hemangiomas with unusually prolonged growth phase: a case series.

BACKGROUND Most infantile hemangiomas (IHs) complete their proliferative growth phase before 9 months of age, but those with unusually prolonged growth create unique clinical challenges. We performed a retrospective case series of IHs with prolonged growth to further characterize these lesions and their treatment. OBSERVATIONS We identified 23 patients as having IHs with prolonged growth after 9 months of age, with growth to a mean age of 17 months. All of the IHs had a deep dermal to subcutaneous component, all had either segmental or indeterminate morphologic characteristics, and 39% involved the parotid gland. A total of 20 of 23 received prolonged treatment with systemic corticosteroids (mean duration of treatment, 11 months), and 9 of 20 received additional systemic therapies (vincristine sulfate and/or interferon alfa-2a or alfa-2b). CONCLUSIONS Prolonged growth was observed primarily in IHs with a deep component and segmental morphologic characteristics. Recognition of this subset of hemangiomas is important for clinicians, and further study of IHs may provide clues to their pathogenesis.