Chronic lymphocytic leukemia with CNS involvement.

Direct involvement of the brain by chronic lymphocytic leukemia (CLL) is extremely rare. This is the second documented case. A 63 year-old-man presented with motor deficits. Conventional radiographic imaging showed no abnormalities but an MRI scan of the head showed a high signal intensity lesion in the left cerebellum. Biopsy of this area showed a perivascular infiltrate of small B lymphocytes consistent with CLL involvement. The patient was treated with radiotherapy and had some improvement in symptoms. Three years later he remains alive with some neurologic deficit. This case confirms that CLL can be complicated by direct brain involvement.