Ncmp-29. the natural history of neurolymphomatosis

Abstract Neurolymphomatosis is a rare lymphoid malignancy of the peripheral nervous system. Patients suffer from debilitating neurological deficits due to lymphoma invasion into one or more peripheral nerves and the natural history of this disease is still poorly understood. We performed a PubMed search and extracted data on year of publication, age, gender, type of lymphoma, nerves involved, imaging modalities, treatment received, and survival times. Kaplan-Meier statistics were used to determine outcome parameters over time and compare prognostic factors. Multiple comparisons were done to determine differences among groups. Our search identified 559 patients from 286 articles. Median age was 61 years (range 2-92) from 326 males, 222 females, and 11 with unspecified gender. Median overall survival (OS) was 12.0 months (range 10.0-15.0) for the entire cohort. Most frequent histologies were diffuse large B-cell lymphoma, unspecified T-cell lymphoma, and unspecified B-cell lymphoma, involving the brachial plexus, cranial nerves, and sciatic nerve. None had molecular profiling. There was a progressive lengthening of OS in successive decades, from 0.5 (95%CI 0.0-0.8) to 26.4 (95%CI 18.0-34.8) months from 1951-2022 (r2=0.9432, p< 0.001). Time from first treatment to progression also increased from 2.0 (95%CI N/A) to 28.3 (95%CI 23.1-33.5) months (r2=0.6923, p< 0.001). However, time from symptom onset to diagnosis remained unchanged during this period (r2=0.6206, p=0.277). Patients were most frequently treated with methotrexate-based chemotherapies (n=81), rituximab-based chemotherapies (n=176), and/or radiation (n=79). Only 12 received 3 or more regimens. Primary neurolymphomatosis had a better prognosis than secondary neurolymphomatosis, median OS 15.0 (95%CI 11.0-33.0) vs. 10.0 (95%CI 10.0-10.0) months (p=0.016). No OS difference was noted between B- and T-cell disease (p=0.4393), while patients with low-grade B-cell neurolymphomatosis did better than those with Burkitt's lymphoma (p≤0.001). Outcome for patients with neurolymphomatosis has improved over time. But timely diagnosis remains a major problem that needs improvement.