Patterns of survival in lymphoplasmacytic lymphoma/Waldenström macroglobulinemia: a population-based study of 1,555 patients diagnosed in Sweden from 1980 to 2005.

Abstract

Clinical management of lymphoplasmacytic lymphoma (LPL)/Waldenström macroglobulinemia (WM) has changed considerably over recent years, reflected in the use of new therapeutic agents (purine analogs, monoclonal antibodies, thalidomide- and bortezomib-based therapies). No population-based studies and few randomized trials have been performed to assess survival in newly diagnosed LPL/WM. We performed a large population-based study in Sweden including 1,555 LPL/WM patients diagnosed from 1980 to 2005. Relative survival ratios (RSRs) and excess mortality rate ratios (EMRR) were computed as measures of survival. Survival of LPL/WM patients has improved significantly (P = 0.007) over time with 5-year RSR = 0.57 (95% confidence interval [CI] 0.46-0.68), 0.65 (0.57-0.73), 0.74 (0.68-0.80), 0.72 (0.66-0.77), and 0.78 (0.71-0.85) for patients diagnosed during the calendar periods 1980-1985, 1986-1990, 1991-1995, 1996-2000, and 2001-2005, respectively. Improvement in 1- and 5-year relative survival was found in all age groups and for LPL and WM separately. Patients with WM had lower excess mortality compared to LPL (EMRR = 0.38; 95% CI 0.30-0.48). Older age at diagnosis was associated with a poorer survival (P < 0.001). Taken together, we found a significant improvement in survival in LPL/WM over time. Despite this progress, new effective agents with a more favourable toxicity profile are needed to further improve survival in LPL/WM, especially in the elderly.