In the November issue of Modern Pathology, the team describe a florid benign vascular proliferation of the colon in 5 adult patients, 3 of whom presented with idiopathic intussusception.
In all cases, the proliferation was sufficiently exuberant to raise the possibility of angiosarcoma as a diagnostic consideration.
The group included 2 males and 3 females, with a median age of 43 years. Of the patients, 2 were HIV positive.
Four patients presented with a colonic mass; other symptoms at presentation included abdominal pain, diarrhea, bleeding, and bowel obstruction.
In all cases, a florid lobular proliferation of small vascular channels lined by plump endothelial cells extended from the submucosa through the entire thickness of the bowel wall.
| All 5 cases with florid vascular proliferation had intussusception or mucosal prolapse.
The endothelial cells showed minimal nuclear atypia, and mitotic figures were infrequent.
The overlying mucosa showed ulceration with ischemic-type changes, and had features of mucosal prolapse.
A possible underlying arteriovenous malformation was identified in 2 cases.
The researchers found that all patients were alive and well at the last follow-up (interval, 6 months to 5 years).
Dr Neil R. Bavikatty, of the University of Michigan Hospitals, Ann Arbor, Michigan, concluded on behalf of the group, "The presence of intussusception or mucosal prolapse in all of the cases suggests repeated mechanical forces applied to the bowel wall as a possible etiologic factor.
"The role of HIV infection in the pathogenesis of these lesions remains to be determined."