No Evidence for Maternal–Fetal Microchimerism in Infantile Hemangioma: A Molecular Genetic Investigation

In this study, using the placental origin theory as a basis, we set out to explore whether hemangioma endothelial cells (HEC) were maternal in origin. We rigorously addressed this hypothesis using several molecular genetic techniques. Fluorescent in situ hybridization on surgical specimens of proliferating hemangiomas (n=8) demonstrated no XX-labeled HEC from resected tumors of male infants. This analysis was followed by PCR genotyping of HEC (n=11) using microsatellite markers where cellular components were genotyped and compared to genomic DNA of corresponding mother-child pairs. In the seven informative mother-child pairs, HEC matched the genotype of the child and not the maternal genotype. Concerned that HEC represented a mixed population of cells, we subsequently enriched for cells using the placental-specific endothelial cell (EC) marker, Fc gammaRII. Three informative mother-child pairs exhibited only the genotype of the child in our enriched cell population. Using sequence analysis, we identified an informative single nucleotide polymorphism in an exon of the placental-EC-specific protein, GLUT1. When comparing GLUT1 complementary DNA (cDNA) with mother-child DNA, the genotype of the cDNA matched the constitutional DNA of the child. Our results indicate that hemangiomas are not microchimeric in origin. This study provides further insight into the origin of a tumor whose pathogenesis remains elusive

How we approach hemangiomas in infants.

Pediatric oncologists are increasingly involved in the management of benign vascular tumors and their associated life-threatening complications. Hemangiomas are the most common referring diagnosis to multidisciplinary vascular anomalies clinics. However, as contemporary research has revealed, hemangiomas are not a single, easily defined entity but rather a diverse set of related vascular tumors, each having a unique natural history, growth pattern, and response to therapy. This manuscript seeks to illustrate how we evaluate and manage these complex tumors, their complications, and associated syndromes, while remaining ever vigilant for malignant hemangioma mimickers such as soft tissue sarcomas and congenital leukemia

Congenital plaque-type glomuvenous malformations presenting in childhood.

BACKGROUND: Glomuvenous malformations (GVMs) are now considered a separate entity from venous malformations. The rarest type of GVM is the generalized congenital plaque-type GVM. OBSERVATIONS: We present 10 new cases of congenital plaque-type GVM and describe their clinical progression and treatment. Mutations in the glomulin gene were found in those patients who participated in the genetic study. CONCLUSIONS: Congenital plaque-type GVMs are unique in their congenital nature, extensive distribution, difficult to diagnose and treat, and progressive involvement after birth. Most cases are familial, yet affected relatives usually have only minor lesions. The lesions of congenital plaque-type GVM are severe, visible at birth, and usually mistaken for extensive venous malformations. Vascular malformations are divided by hemodynamic type into slow-flow and fast-flow lesions. Slow-flow lesions are subcategorized as capillary, lymphatic, and venous.(1) Capillary malformations are flat, sharply demarcated, red-pink vascular stains of the skin commonly referred to as port-wine stains. These persist throughout life and are characterized histologically by dilated capillaries within the dermis. They slowly increase in size with age. Lymphatic malformations are spongelike collections of abnormal channels and spaces that contain clear lymphatic fluid, causing an excess of fluid to accumulate and dilate the lymphatic channels. This results in swelling of the affected area and, if extensive, can cause enlargement of soft tissues and bones