Epstein-Barr virus in monitoring the response to therapy of acquired immunodeficiency syndrome-related primary central nervous system lymphoma

To evaluate the value of Epstein-Barr virus DNA (EBV-DNA) assay in cerebrospinal fluid (CSF) for monitoring the response to treatment in acquired immunodeficiency syndrome-related primary central nervous system lymphoma (AIDS-PCNSL), 9 human immunodeficiency virus-infected patients with biopsy-proven AIDS-PCNSL who underwent multimodal therapy were investigated for EBV-DNA detection in CSF by semiquantitative nested polymerase chain reaction (PCR). Tumoral tissue expression of bcl-6 oncogene protein and of EBV-encoded latent membrane protein (LMP-1) was also investigated. The 2 patients who had a response to chemotherapy showed a reduction of mean EBV- DNA concentration values after chemotherapy and displayed a large noncleaved morphology and a BCL-6⁺/LMP-1^- phenotype. Conversely, the 4 patients with progressive disease after chemotherapy showed increasing mean values of EBVDNA and displayed an immunoblastic morphology and a BCL-6^-/LMP-1⁺ phenotype. No significant changes were observed for patients with stable disease. EBV-DNA burden reduction was significantly associated with prolonged survival. These results suggest that EBV-DNA monitoring might be helpful in predicting response to chemotherapy and in segregating distinct biological and prognostic categories of AIDS-PCNSL.