Clinical features and survival outcomes of patients with lymphoplasmacytic lymphoma, including non-IgM type, in Korea: a single-center experience

BACKGROUND: The incidence of lymphoplasmacytic lymphoma (LPL) is lower in Asian than in Western populations. Few studies have described the clinical features and treatment outcomes of patients with LPL, including non-IgM LPL, in East Asia. METHODS: We retrospectively analyzed patients diagnosed with LPL at Asan Medical Center between January 2001 and March 2016. We evaluated the clinical features and survival outcomes of patients with LPL and non-IgM LPL and compared these data with those of patients with LPL/Waldenström's macroglobulinemia (WM). RESULTS: The median age at diagnosis of patients with LPL was 61.5 years (range, 34–77 yr); most patients were male (91%). Approximately three-quarters of the 22 patients with LPL were in the low or intermediate risk groups according to the International Prognostic Scoring System for Waldenström's Macroglobulinemia classification. The median follow-up duration was 75 months [95% confidence interval (CI), 48–102 mo], and the median overall survival (OS) was 81 months (95% CI, 0–167 mo). The number of patients in the non-IgM LPL group who exhibited extramedullary involvement was higher than in the LPL/WM group. OS of the LPL/WM group was improved compared with that of the non-IgM LPL group [median not reached vs. 10.0 mo (95% CI, 0–36.7); P=0.05]. CONCLUSION: We present a single-center experience of 22 patients with LPL, including a non-IgM cohort, in Korea. The treatment of non-IgM LPL was heterogeneous, and patients with non-IgM LPL showed a higher 5-year mortality rate and more adverse prognostic factors than those with LPL/WM.