Abstract: Objective To analyze the clinical features of patients in splenic marginal zone lymphoma (SMZL) with MYD88 L265P mutation. Methods The cases of SMZL patients in Chinese Academy of Medical Sciences were retrospectively reviewed, and the features of MYD88 L265P mutation patients were compared with those of the wild-type and Waldenstr-m macroglobulinemia (WM) patients. Results In the SMZL patient cohort of Chinese Academy of Medical Sciences, the rate of MYD88 L265P mutation was 10.3% (7/68). Compared with the wild-type SMZL patients of the same gene, the mutants were all elderly patients (100.0% vs 56.3%, P=0.038), and B symptoms were more likely to occur (85.7% vs 42.1%, P=0.046), and the positive rate of M protein was higher (85.7% vs 46.2%, P=0.043). In contrast to WM patients, SMZL patients were rarely lymph node-involved (28.6% vs 61.3%), and had no hyperviscosity and a relatively low positive rate of monoclonal protein (85.7% vs 100.0%), one third of which had non-IgM type. Conclusions The SMZL patients with MYD88 L265P mutation shows some clinical features, and the diagnosis should be based on morphological classification combined immunological/histoimmunochemistry. Patients with difficulty in diagnosis further examined for 7q31 deletion, IGHV mutation status, NOTCH2 and KLF2 mutation may help for diagnosis.

Key words: Splenic marginal zone lymphoma, Lymphoplasmacytic lymphoma, Waldenstr-m macroglobulinemia, MYD88 L265P mutation