IgM monoclonal gammopathy in gastric MALToma

[Marginal zone lymphoma with monoclonal immunoglobulin: three cases report and literatures review]

OBJECTIVE

To investigate the clinical features and treatment in patients of marginal zone lymphoma (MZL)with monoclonal immunoglobulin (McIg).

METHODS

The clinical data of MZL patients with McIg, including 3 cases diagnosed and treated in Beijing Anzhen Hospital from Jan 2007 to Dec 2014 were retrospectively studied, meanwhile 36 patients searched from literatures were reviewed.

RESULTS

Of a total of 39 patients, the ratio of male and female was 1.05∶1 with an average age of 65.1± 12.3 years old. 28 cases (71.8%)were with mucosa associated lymphoid tissue lymphomas (MALTL), 9 cases (23.1% )with nodal marginal zone lymphoma, and 2 cases (5.1%)with splenic marginal zone lymphoma. Nine cases (23.1% )were in the early stage, 30 cases (76.9%)in the advanced stage. The common initial symptom was non-mass lesions (65.5%), such as skin purpura, peripheral neuropathy; 13 patients (33.3% )were accompanied by autoimmune phenomenon, and most were with Sjogren's syndrome. Among MALTL patients, the common primary lesion was in non- gastrointestinal tract (17 cases, 60.7%). Most of patients with McIg were one with McIgM (82.0%); the others with McIgA, Mcκ-light chain, McIgG and double McIg. The level of plasma McIgM was (25.55±21.31)g/L, which was higher in advanced stage patients than in early stage ones [(29.85±20.60)g/Lvs (3.23±2.95)g/L,P= 0.008]. The complete remission (CR)rate was 56.0% and the overall response rate (ORR)92.0%, respectively in 30 patients treated by chemotherapy. At a median follow- up of 10 months, the 3- year progression free survival and the 3-year overall survival were 44.7% and 76.5%, respectively. The rates of ORR and CR in the patients received rituximab- included regimen were seemly better than those without rituximab one (100.0%vs 78.6%, 63.6%vs 50.0%;P>0.05), but no statistic differences were found. The CR rate in patients with McIgM was significantly higher than that with non- McIgM (P=0.026). The plasma McIgM level decreased after chemotherapy (P=0.002).

CONCLUSION

The MZL with McIg, perhaps a kind of unique subtype, usually occurred in 60 years or older patients. It was often diagnosed in patients of advanced stage and susceptible to autoimmune phenomenon. MALTL in non- gastrointestinal tract was more prone to find McIg. In MZL patients with McIg, McIgM was more common and other McIg rare. Rituximab-included regimen produced a better therapeutic response.