[Clinical characteristics and prognosis of primary and secondary diffuse large B-cell lymphoma of the pancreas]

Objective: To analyze the clinical characteristics and prognosis of primary and secondary pancreatic diffuse large B-cell lymphoma (DLBCL) . Methods: Clinical data of patients with pancreatic DLBCL admitted at Shanghai Rui Jin Hospital affiliated with Shanghai Jiao Tong University School of Medicine from April 2003 to June 2020 were analyzed. Gene mutation profiles were evaluated by targeted sequencing (55 lymphoma-related genes). Univariate and multivariate Cox regression models were used to evaluate the prognostic factors of overall survival (OS) and progression-free survival (PFS) . Results: Overall, 80 patients were included; 12 patients had primary pancreatic DLBCL (PPDLBCL), and 68 patients had secondary pancreatic DLBCL (SPDLBCL). Compared with those with PPDLBCL, patients with SPDLBCL had a higher number of affected extranodal sites (P<0.001) and had higher IPI scores (P=0.013). There was no significant difference in the OS (P=0.120) and PFS (P=0.067) between the two groups. Multivariate analysis indicated that IPI intermediate-high/high risk (P=0.025) and double expressor (DE) (P=0.017) were independent adverse prognostic factors of OS in patients with pancreatic DLBCL. IPI intermediate-high/high risk (P=0.021) was an independent adverse prognostic factor of PFS in patients with pancreatic DLBCL. Targeted sequencing of 29 patients showed that the mutation frequency of PIM1, SGK1, BTG2, FAS, MYC, and MYD88 in patients with pancreatic DLBCL were all >20%. PIM1 (P=0.006 for OS, P=0.032 for PFS) and MYD88 (P=0.001 for OS, P=0.017 for PFS) mutations were associated with poor OS and PFS in patients with SPDLBCL. Conclusion: There was no significant difference in the OS and PFS between patients with PPDLBCL and those with SPDLBCL. IPI intermediate-high/high risk and DE were adverse prognostic factors of pancreatic DLBCL. PIM1, SGK1, BTG2, FAS, MYC, and MYD88 were common mutations in pancreatic DLBCL. PIM1 and MYD88 mutations indicated worse prognosis.