Ring-enhanced primary intracranial malignant lymphoma--report of two cases

Two nonimmunosuppressed patients with primary intracranial malignant lymphoma demonstrated ring-enhanced lesion on postcontrast CT scans. One patient underwent total removal of the tumor and the other patient biopsy, both followed by whole brain irradiation. Histological examination revealed the tumors contained diffuse large cells and necrosis in the central region. The possible mechanisms of ring enhancement may represent central necrosis of the rapidly growing tumor, but is probably not related to the prognosis.