The neurologic complications of B-cell chronic lymphocytic leukemia.

We performed a retrospective study to characterize the type, frequency, and timing of neurologic complications in patients with B-cell chronic lymphocytic leukemia (B-CLL). We reviewed 962 total charts with a median follow-up time of 57.5 months. There were 109 cases (11.3%) of neurologic complications, including 69 cases (7.2%) of herpes zoster infection, 17 cases (1.8%) of other opportunistic infection, 14 cases (1.5%) of treatment-related conditions, eight cases (0.8%) of direct leukemic involvement of neural tissue, and 1 case (0.1%) of intracranial hemorrhage. No cases of a non-zoster opportunistic infection presented in early-stage (Rai stage 0-2) B-CLL, and only one case of direct leukemic involvement of neural structures presented in early-stage B-CLL. Of the 25 cases of non-zoster or treatment-related complications, only 5 presented before 6 years from the initial B-CLL diagnosis. Three of these were in advanced-stage B-CLL, staging could not be determined in one, and one presented in early-stage B-CLL. We conclude that the overall neurologic complication rate of B-CLL is low, and that the Rai stage of the disease correlates best with the risk of developing neurologic complications. The occurrence of a related non-zoster neurologic complication in a patient with B-CLL stage 0-2 approaches 1:1,000.