We reviewed the consultation files of the ARmed Forces Institute of Pathology for 1951 through 1989 and identified fourteen patients who had had skeletal-extraskeletal angiomatosis. Skeletal-extraskeletal angiomatosis was defined as a benign vascular proliferation involving the medullary cavity of bone and at least one other type of tissue. The age of the patients at the time of initial biopsy ranged from nine months to sixty-nine years (average, twenty-two years; median, ten years). Ten of the patients were male and four were female. The presenting signs and symptoms were highly variable; they included pain (four patients), a mass noted at birth (three patients), a painless mass that developed after birth (two patients), both pain and a mass (one patient), a localized deformity of the thoracic spine (one patient), and anemia associated with chronic bleeding of the gastrointestinal tract (one patient); in this last patient, skeletal lesions subsequently were found and biopsied. Skeletal-extraskeletal angiomatosis was an incidental finding in the remaining two patients. Multiple bones were involved in thirteen of the fourteen patients. Histologically, three patterns of lesion could be identified: cavernous lymphangioma (six patients), cavernous hemangioma (six patients), and arteriovenous hemangioma (two patients). Five of the patients died (three of sepsis associated with persistent lesions of angiomatosis and two of unrelated causes); eight of the patients survived but had residual disease, and one survived and had no evidence of residual disease.