Signet-ring cell lymphoma of the central nervous system. Case report.

Signet-ring cell lymphoma is a rare tumor described in the lymph nodes, skin, tonsils, thyroid, salivary gland, and ocular orbit. This is the first case report of a B-cell signet-ring cell lymphoma in the central nervous system with Dutcher and Russell bodies, signet-ring nuclei, intracisternal crystalline inclusions, and immunoglobulin M positivity. The patient is doing well 2 years after surgery and postoperative radiation therapy. No definitive prognostic characteristics have been elucidated. This disease entity can only be suspected on histological grounds and confirmed by immunocytochemical and ultrastructural studies.