[Risk assessment and prophylactic treatment strategies for central nervous system relapse of diffuse large B-cell lymphoma].

Rituximab treatment significantly improved the outcomes of diffuse large B-cell lymphoma (DLBCL). A central nervous system (CNS) relapse remains a serious and fatal event for patients with DLBCL; therefore, the clinical question of the optimal treatment regimen for reducing the risk of CNS relapse remains unknown. The CNS-International Prognostic Index was identified as a predictive model for CNS relapse. No factors can completely predict CNS relapse although several reports regarding high-risk factors for CNS relapse have been reported. In practice, intrathecal methotrexate (MTX) and high-dose MTX therapy have been used for CNS prophylaxis. Unfortunately, evidence of the optimal therapy for CNS prophylaxis in patients with DLBCL remains lacking. This study aimed to review CNS relapse assessment and discuss study results with clinical impacts on CNS prophylaxis treatment strategies in DLBCL.

Advances in risk assessment and prophylaxis for central nervous system relapse in diffuse large B-cell lymphoma.

Central nervous sytem recurrence of diffuse large B-cell lymphoma is an uncommon but devastating event, making identification of patients at high risk for relapse within the central nervous system essential for clinicians. Modern risk stratification includes both clinical and biological features. A validated clinical risk model employing the five traditional International Prognostic Index risk factors plus renal or adrenal involvement can identify a high-risk patient population with a central nervous system recurrence risk of greater than 10%. Lymphoma involvement of certain discrete extranodal sites such as the testis also confers increased risk, even in stage I disease. Adverse biological risk factors for central nervous system relapse include presence of translocations of MYC, BCL2 and/or BCL6, in so-called double- or triple-hit lymphoma. Immunohistochemically detectable co-expression of MYC and BCL2 in the absence of translocations also portends an increased risk of relapse within the central nervous system, particularly in the setting of the activated B-cell-like subtype of diffuse large B-cell lymphoma. The role, method, and timing of prophylactic therapy remain controversial based on the available data. We review both intrathecal and systemic strategies for prophylaxis in high-risk patients. Our preference is for systemic methotrexate in concert with standard chemoimmunotherapy in the majority of cases. Several novel agents have also demonstrated clinical activity in primary and secondary central nervous system lymphoma and warrant future investigation in the prophylactic setting.