Blue rubber bleb nevus syndrome: novel lymphangiomatosis-like growth pattern within the uterus and immunohistochemical analysis

SummaryBlue Rubber Bleb Nevus Syndrome is a rare, primarily sporadic condition characterized by vascular lesions principally involving the skin and gastrointestinal tract. Although considered a venous malformation, telangiectatic capillaries, arteriovenous malformations, and lymphangiomas have been reported, but a lymphangiomatosis-like growth pattern has not been described. This case of Blue Rubber Bleb Nevus Syndrome demonstrated a labyrinth of variably sized vascular spaces lined by an attenuated layer of bland endothelial cells, dissecting uterine tissues and sequestering remaining myometrium. Immunohistochemical profile of lesional endothelial cells from the myometrium included strong, diffuse CD31; variable CD34; strong, patchy D2-40; weak, patchy factor VIII–related antigen; focal linear subendothelial collagen type IV; Ki-67 in 1% of cells; and no GLUT-1 or WT1 expression. This report expands the morphological spectrum of vascular lesions in Blue Rubber Bleb Nevus Syndrome to include a lymphangiomatosis-like growth pattern and the immunohistochemistry suggests dual vascular and lymphatic differentiation, supporting the current belief that these lesions are malformations.