A case of central nervous system lesion pathologically characterized by angiocentric, T-cell-rich lymphoid cell infiltrates: a case report and literature review.

Lymphomatoid granulomatosis (LYG) is a rare lymphoproliferative disease with angiocentric and angiodestructive infiltrates, and by definition, Epstein-Barr virus (EBV)-associated B-cell malignancy. It most frequently involves the lung, and in some cases, the lesions are confined to the central nervous system (isolated CNS-LYG). However, it remains a controversial disease in terms of pathophysiology, especially in those confined to the CNS. We report the case of a 37-year-old man with CNS lesion pathologically characterized by angiocentric, T-cell-rich lymphoid cell infiltrates that resembled CNS-LYG. The lesion was clinically aggressive with subacute onset and irregular ring-like enhancement on MRI. The resected specimen showed no cytological atypia, EBV-infected cells, or monoclonality for IgH and TCR gene rearrangements. Considering the possibility of latent malignancy, the patient was successfully treated with corticosteroid and chemoradiotherapy with high-dose methotrexate. The present case and the literature suggest that EBV-negative CNS lesions with angiocentric lymphoid infiltrates are probably heterogeneous in their pathogenesis, including those that could fit into the so-called CNS-LYG and those with T-cell predominance. The accumulation of similar cases is warranted for the classification and appropriate treatment of these lesions.