O04 Segmental congenital haemangioma: a novel subtype of a rare vascular tumour

Abstract

Abstract Congenital haemangiomas (CH) are rare vascular tumours present at birth. These high-flow vascular lesions can lead to significant morbidity secondary to high-output cardiac failure (HOCF) and Kasabach–Merritt phenomenon (KMP). They are classically round/oval lesions and present anywhere on the body. The majority involute spontaneously in the first 2 years of life. We describe three patients who presented with an unusual segmental pattern CH of the head/scalp: the first with a segmental CH of the left forehead, extending over the left eye with associated ipsilateral heterochromia and anisocoria; the second with a segmental ulcerated CH of the right scalp – catastrophic haemorrhage from the CH sadly resulted in death at age 6 weeks; the third with a left forehead segmental CH. None of the CH in this series developed HOCF or KMP. All lesions were consistent with CH on sonography and histology where available. Patients 1 and 3 exhibited spontaneous involution in the first 2 years of life. Segmental CH have been reported once before in a series of three patients, although involving the arm/trunk rather than the head. Two of the three patients developed KMP/HOCF. The genetic basis in this cohort was identical to that of classic nonsegmental CH, activating somatic mutations in GNAQ/11. The striking segmental pattern in our cohort is likely attributable to the timing of the somatic hit during development. Identification of this pattern in CH gives important insights into vascular tumorigenesis. Further cohort studies are needed to determine if this group has differing clinical outcomes from classical CH.