Tumoral presentation of primary central nervous system lymphomatoid granulomatosis

Purpose Lymphomatoid granulomatosis (LYG) is an angiocentric Epstein-Barr virus (EBV) related B-cell proliferation associated with a reactive T-cell component with an uncertain malignant potential. LYG present at diagnosis as a mass lesion in the central nervous system (CNS) is rare, and only a few cases have been reported. In this article we present four cases of tumoral CNS-LYG and propose some guidelines for its management. Methods Clinical, pathological, imaging and laboratory information of four immunocompetent patients, all of them treated surgically, with a final diagnosis of LYG and presenting with an isolated intracranial tumoral mass is reviewed. Results Two parenchymal lesions were located in the cerebellum and temporal lobe, and the other two involved the cavernous sinus. At surgery they were avascular, hard, lard-like, necrotic and plastic well-defined lesions, with invasion of the leptomeninges and thrombosis of the small leptomeningeal arteries and veins. Intraoperative pathology excluded any tumor. Pathological studies showed a polymorphic and polyclonal infiltration around, in the wall and into the lumen of medium-sized cortical and leptomeningeal vessels causing their obstruction and tissular necrosis. EBV-infected cells were present. Conclusions Making a preoperative diagnosis of CNS-LYG appearing initially as a tumoral mass is difficult because of the lack of pathognomonic clinical symptoms or imaging signs. Surgical management with radical resection of the mass is almost always followed by the long-term local control of the lesion, although the disease may have a disseminated, systemic or malignant evolution.