Surprisingly, the proportion of IL-10-secreting Bregs after 24 h of in vitro maturation with CpG ODN 2006 and CD40L was significantly lower in the tumor samples than in matched peripheral blood B cells (2.74 ± 0.53% vs. 8.01 ± 1.75%, respectively; p = 0.039), but similar to the levels of Bregs in control tonsils (2.16 ± 1.51%). This evidence concerns the gene IL10 and neoplasm.