Prognostic factors in primary central nervous system lymphomas

Two major categories of prognostic factors exist in patients who have PCNSL: the classic prognostic factors for non-Hodgkin's lymphoma and specific prognostic factors for PCNSL. Among the parameters used in the IPI, age, PS, and serum LDH level are generally correlated to survival. A significant association between survival and involvement of deep structures of the brain and elevated CSF protein concentrations has been reported. In the IELSG series of 378 cases, classic and PCNSL-specific prognostic factors were established as independent prognostic factors. These variables were used to develop a prognostic scoring system (the IELSG score) that distinguishes three different risk groups. The IELSG score will improve further with a better knowledge of these malignancies, especially with the inclusion of new variables able to identify lymphomas with different chemosensitivities or degrees of aggressiveness. Clinical variables, molecular features, and pharmacogenetic markers may be useful predictors of iatrogenic toxicity, leading to adequate prevention and outcome improvement. The identification of reliable prognostic factors in PCNSL may allow the separation of patients into risk groups, which could result in the application of risk-adjusted therapeutic strategies.