Hepatic hemangiomas are the most common benign liver tumors of infancy. They are termed congenital if fully developed at birth or infantile if they appear in the first weeks of life. Previous studies suggested that most focal hepatic hemangiomas are congenital in nature, exhibit no postnatal growth and have an evolution that parallels their cutaneous counterparts. They are subdivided by pattern of involution, whether rapidly involuting (RICH), partially involuting (PICH) or non-involuting (NICH) congenital hemangiomas. In our experience, some focal hepatic hemangiomas show postnatal growth, behaving like infantile forms. To analyze the spontaneous evolution of focal congenital hepatic hemangiomas with quantification of tumor volume changes over time and to identify initial postnatal ultrasound (US) imaging biomarkers predictive of their evolution pattern. A retrospective review of clinical, imaging and pathology data of children diagnosed with focal congenital hepatic hemangioma (prenatal diagnosis or age at diagnosis <7days and/or glucose transporter protein 1 [GLUT1]-negative tumor) diagnosed between 2000 and 2018 was performed with analysis of tumor volume changes over time. Exclusion criteria were treatment inducing a tumor volume change (hepatic artery embolization, propranolol, or corticosteroids), imaging follow-up less than 1month or fewer than two US examinations. Volumetric analysis was based on US and cross-sectional imaging. Lesion volumes were estimated using the standard ellipsoid formula. A 35% margin of error was assumed for tumor volume variation to account for variability in measurements. Imaging studies, including US, computed tomography, and magnetic resonance imaging, were reviewed and initial postnatal US features were correlated with evolution pattern. Twenty-five patients with focal congenital hepatic hemangiomas were included. The median follow-up time was 46.5months (range: 4-144months). Eight (32%) lesions showed postnatal growth before involuting, without signs of intralesional hemorrhage, as do cutaneous infantile hemangiomas. The other 17 (68%) lesions exhibited a strict decrease in volume with age, of which 15 underwent complete involution (8 before age 18months and 7 after age 18months) and 2 underwent partial involution. The different evolution patterns of focal congenital hepatic hemangiomas showed overlapping imaging features and we found no initial US feature to be significantly associated with postnatal growth. However, large vascular spaces with marked vascularity at US were noted in three of the eight rapidly involuting lesions. Focal congenital hepatic hemangiomas are not the equivalent of cutaneous RICH, as some may increase in size and tumor regression may be rapid or slow. The different evolution patterns of focal congenital hepatic hemangiomas show overlapping US features.
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