HISTOPATHOLOGICAL STUDY OF THE VASCULAR LESIONS IN NEUROFIBROMATOSIS

ABSTRACT

Clinical manifestations caused by vascular complications including stenosis, occlusion, aneurysm and arteriovenous malformation were rarely developed in patients with neurofibromatosis. We reviewed 23 cases of neurofibromatosis type I to identify the histopathologic features of vessels in neurofibromatosis associated with clinical features. The results were as follows: 1. The age of patients ranged from 4 to 61 years(mean: 23 years) at diagnosis and sex ratio of male to female was 1.3 : 1. The family history was present in 52%(12/23) of the patients. Angiographically, 3 cases of atherosclerosis, 1 case of arteriovenous malformation, and 1 case of aneurysm were seen. 2. peculiar vascular alternations were found in 7 of 23 cases of neurofibromatosis, which were classified as 4 types: 6 cases of pure intimal; 3 cases of advanced intimal; 1 case of intimal-aneurysmal; 3 cases of nodular type. The most frequent type of vascular lesions was observed in the patients with neurofibromatosis was Pure intimal, and the most uncommon one was intimal-aneurysmal. 3. Immunohistochemically, the positivity to S-100 protein was noted in the tumor cells arranged in the periphery of vessels, but no reaction was seen in the spindle or epithelioid cells within the vascular wall. In conclusion, the vascular lesions associated with neurofibromatosis may result from abnormal proliferation of cells in the vascular wall, possibly smooth muscle cells, not Schwann cells in origin. The various types of lesions described previously appear to be of stage of development.