Cytofluorimetric study of cerebrospinal fluid at staging of diffuse large B cell lymphoma

= 0.04), whereas CSF immunophenotyping and morphology at diagnosis were not. Notably, both patients who developed CNS relapse had received prophylaxis-one with intrathecal methotrexate and the other with high-dose intravenous methotrexate following R-CHOP. CSF analysis at diagnosis using immunophenotyping, morphology, and chemical-physical evaluation was not predictive of CNS recurrence. Moreover, CSF positivity at diagnosis is exceedingly rare, even among patients with high CNS-IPI. Our findings reinforce that CNS-IPI remains the most reliable predictor of CNS relapse in DLBCL.