A case series of tardive expansion congenital hemangioma: A variation of noninvoluting congenital hemangioma or a new hemangiomatous entity?

Background: Congenital hemangiomas present fully grown at birth and share a remarkably similar lack of disproportionate or accelerated postnatal proliferation.Objective: We report a series of unusual congenital hemangiomas that arise prenatally and initially exhibit a proportional growth pattern similar to that of noninvoluting congenital hemangioma. However, a tardive expansion of the lesion, similar to the proliferation phase of infantile hemangioma, occurs later during childhood.Methods: A total of 11 unusual congenital hemangiomas were reviewed in regard to clinical presentation, imaging, and pathologic characteristics.Results: The infants included 9 boys and 2 girls. The tumors were located in the head and neck (n=10) and abdominal wall (n=1). Spontaneous expansion began at the age of 12 months to 61 months, as determined from clinic notes and paired follow-up photographs. Uniform parenchymal masses and fast-flow vessels were confirmed by imaging examination. There are both histopathological overlap and distinction between these lesions and other congenital hemangiomas.Limitations: Only a small number of cases were identified.Conclusion: We propose that these lesions be denominated "tardive expansion congenital hemangioma (TECH)'' to indicate their specific clinical and histological distinctiveness. Recognition of these distinct lesions will contribute to a better understanding of congenital hemangiomas.