Prognostic factors in follicular lymphoma: the importance of beta-2 microglobulin.

Aims and background. The Follicular Lymphoma International Prognostic Index (FLIPI) is a useful tool for the prognostic assessment of follicular lymphoma but beta-2 microglobulin (B2M) was not incorporated in this index. We aimed to compare the predictive value of B2M, FLIPI and other prognostic factors not included in the FLIPI index for overall survival (OS), complete remission (CR), and time to treatment failure (TTF) in a nonselected follicular lymphoma series. Methods and study design. Retrospective univariate and multivariate analysis of the prognostic value (for OS, CR, fin of B2M, FLIPI and other prognostic variables in follicular lymphoma was conducted in a cohort of follicular lymphoma patients between 1987 and 2007. Results. One hundred and six patients were studied. In univariate analysis B2M and B symptoms were significantly associated with OS, and FLIPI only detected two risk levels. In multivariate analysis of OS only two significant variables were found: FLIPI and B2M. Multivariate analysis of CR showed that normal B2M, absence of a bulky mass, uninvolved bone marrow, and chemotherapy with rituximab were significant predictors of CR. FLIPI (three levels), B2M, bone marrow infiltration, and chemotherapy with rituximab were significantly associated with TTF. Conclusions. We found a high predictive value of B2M for OS, CR, and TTF. B2M and FLIPI were the most important variables to predict OS. However, in our series FLIPI differentiated only between two mortality risk levels. Free full text available at www.tumorionline.it