A case of solitary intracranial granuloma, most likely to be sarcoidosis

A surgical case of a frontal lobe mass, which was thought to be sarcoidosis, is presented. A 54-year-old woman noticed difficulty in the movement of the lower extremities and gait disturbance in July, 1983. In Jan., 1984, she became unable to walk by herself. A weakness of the left upper extremity appeared, and she consulted us. On examination, abnormal findings were drowsiness, flaccid hemiparesis, left hemihypesthesia, and urinary incontinence. A CT scan revealed an isodense-slightly high dense mass in the subcortical region of the right frontal lobe, surrounded by a marked low-density area. The mass lesion was homogeneously enhanced with a contrast material. Angiography demonstrated only an avascular mass lesion. The routine laboratory data of the blood and the urine, including serum calcium, were within normal limits. Through a right front-parietal craniotomy, the tumor was totally removed. A histological examination disclosed that the granuloma was composed of epithelioid cells, lymphocytes, fibroblasts, and some multinucleated giant cells. Tuberculosis was excluded by a bacterial examination of the mass and by the absence of any demonstrable lesions other than that in the brain. The mass, therefore, showed sarcoidosis. A month after operation, she had no abnormal neurological signs and could walk out of the hospital. Sarcoidosis may involve the nervous system, but rarely the brain. Differentiation from other mass lesions may be different in the absence of disease elsewhere, and the proper treatment is uncertain. The CT findings in the previously reported cases of solitary intracerebral neurosarcoid masses showed slightly hyperdense lesions, with a marked enhancement with contrast material. (J.P.N.)