Tumour-like mass lesion: an under-recognised presentation of primary angiitis of the central nervous system.

Abstract

To describe the occurrence of mass lesions (ML) in primary angiitis of the central nervous system (PACNS) and assess the utility of diagnostic testing and treatment. We examined the case records of the Cleveland Clinic (CC), Massachusetts General Hospital (MGH), and the English language medical literature, for biopsy-proven PACNS cases presenting as a solitary ML. Relevant clinical variables were extracted and analysed with JMP software. We identified a total of 38 ML: eight of 202 (4.0%) patients with CC/MGH and 30 of 535 (5.6%) patients with PACNS identified from the medical literature. A higher percentage (13 of 45; 29%) was seen in the amyloid-related angiitis subset. Poorer outcomes were reported in the amyloid group, with five deaths. Of the non-amyloid group, better outcomes were seen in the group treated with corticosteroids and cyclophosphamide as compared with the group treated with corticosteroids alone. Although rare, PACNS should be considered in the differential diagnosis of ML; greater awareness of this manifestation may facilitate more prompt diagnosis and treatment. Biopsy evidence of angiitis is required for diagnosis; specimens should routinely be stained for amyloid. While excision of the lesion may be curative, aggressive immunosuppressive therapy is associated with favourable outcomes and may obviate the need for surgery.