Multiple cutaneous and noncutaneous (mainly gastrointestinal tract) venous malformations, which can result in discomfort, hemorrhage, and dysfunctions of affected organs.
The first description is credited to M. Gascoyen, who in 1860 allegedly described a patient who suffocated from this type of nevus in the parotid gland. However, it bears the name of the American internist William Bennett Bean (1909-1989), who was the first to fully describe the disorder and also coined its descriptive name in 1958.
Estimates place it in the range of 1:14,000 live births and almost 300 cases have been described in the literature. Men and women are equally affected. It occurs in all races.
Most cases are sporadic, but autosomal dominant inheritance with linkage to chromosome 9p has been described. The mechanistic target of rapamycin (mTOR) complex, a protein kinase, may be involved in the growth regulation of these lesions, particularly given the fact that vascular endothelial growth factor (VEGF) can function as an upstream stimulator in the mTOR signaling pathway, thus promoting angiogenesis. Molecular studies in one patient revealed high expression of stem cell growth factor receptor (c-kit; a marker for angiogenesis in this context) in the vascular lesions, which was associated with an elevated expression of the proliferation marker MIB1.
In nearly a third of the patients, the vascular malformations are already detectable at birth. Almost two-thirds are discovered in childhood, while the remainder is noted during adolescence or adulthood. These venous malformations typically occur on the skin (in over 90% of patients; commonly trunk, upper extremities, perineum), in the gastrointestinal tract (in 75%; from lips to anus), but they can principally occur in any organ system/tissue of the body (oral cavity lesions may occur in up to 60% of patients). Intracranial (in over 10% of patients), spinal canal/vertebral (around 3%) lesions are particularly concerning for anesthesiologists.
The vascular malformations are highly variable with regards to size (from a few millimeters to bulky lesions measuring several centimeters in diameter), to color (from red to black), to morphology (from flat to elevated or even pedunculated nodules), to number (from a few to hundreds) and to location. Histopathological examination reveals ectatic and cavernous venous vessels lined with a single endothelial cell layer on a thin wall of smooth muscle and stroma cells. Clinically, three types of lesions can be distinguished: a) irregular macular lesions with dark blue discoloration diffusely disseminated throughout the body; b) soft to rubber-like, dark purple-blueish lesions with a smooth or wrinkled surface, easily compressible and promptly refilling after the pressure is released; c) large (vascular or cavernous), space-occupying lesions with the potential for compression of adjacent tissues. Existing lesions can change ...