Novel Therapies for Follicular Lymphoma and Other Indolent Non-Hodgkin Lymphomas

When selecting therapy for patients with indolent non-Hodgkin lymphoma (iNHL) including follicular (FL), marginal zone (MZL), small lymphocytic (SLL), and lymphoplasmacytic lymphoma (LPL)/Waldenström macroglobulinemia (WM), there are several factors to consider. With a median age around 70 at diagnosis, many patients have accumulated comorbid conditions that may limit treatment options. Although incurable for most, iNHL is a chronic disease with a median overall survival measured in years to decades. This long natural history changes the risk-to-benefit balance with a lower acceptance of toxicity early in the treatment course compared to that of aggressive lymphomas. Despite a recent rapid increase in available therapies, overall progress in iNHL has been slow for several reasons. Initial trials grouped iNHLs together making it challenging to appreciate the differential activity among subtypes. We have not been able to develop prognostic models that maintain validity in the era of chemotherapy-free options. Predictive markers have been elusive and without identified molecular signatures, it is challenging to select and sequence therapy. With these clinical factors in mind, in addition to the heterogeneity among and within iNHLs, I do not have a standard treatment algorithm and feel each patient should have an individualized treatment approach. This review focuses on recent updates and controversies in the management of iNHL with a focus on FL and MZL.