Value of cerebrospinal fluid white cell count and protein level in predicting leptomeningeal involvement by systemic aggressive B-cell lymphoma.

Statistically significant associations exist between elevated WCC and protein and MFC positivity, and selected WCC and protein cut-off values have PPVs comparable to that of cytological assessment. Whilst routine WCC and protein analysis may be unnecessary, WCC/protein values above these levels could be regarded as reasonable evidence of CSF involvement in the appropriate setting.