Prognostication of Follicular Lymphoma: A Review of Prognostic Scores and Factors

Follicular lymphoma (FL) is an indolent, rarely curable B-cell malignancy with a heterogeneous clinical course. While generally treatable, FL is characterized by remissions and relapses, and its clinical presentation varies widely. Rituximab has revolutionized FL treatment, significantly improving overall survival over the past two decades. Risk assessment typically relies on histological grade, tumor burden, and the Follicular Lymphoma International Prognostic Index, which incorporates factors like age, hemoglobin level, and Ann Arbor stage. However, these indices have limitations in fully capturing the clinical variability of FL. Some patients experience indolent disease for extended periods without requiring treatment, while others present with aggressive forms resistant to standard therapies. This review examines various prognostic factors in FL, including the FLIPI, FLIPI2, PRIMA-PI, and m7-FLIPI. The FLIPI, based on five risk factors, stratifies patients into low-, intermediate-, and high-risk groups. The FLIPI2 incorporates beta2-microglobulin and the longest diameter of the largest involved node, offering improved prognostication. The PRIMA-PI, designed for patients receiving rituximab-containing regimens, uses beta2-microglobulin, bone marrow involvement, and the longest diameter of the largest involved node. The m7-FLIPI integrates mutational status with FLIPI2 parameters, further refining risk stratification. The review also discusses clinical parameters like maximum standardized uptake value on PET/CT and lymphocyte/monocyte ratio as prognostic factors. A high SUVmax and low lymphocyte/monocyte ratio identify high-risk patients. While FL remains incurable, advances in immunochemotherapy and targeted therapies have improved outcomes. This review provides a comprehensive overview of prognostic tools in FL, emphasizing the importance of risk stratification for personalized treatment strategies.