BCL10 expression pattern in MALT lymphoma. (A) A gastric MALT lymphoma shows strong BCL10 nuclear expression similar to that found in those with t(1;14)(p22;q32). (B) A t(11;18)(q21;q21)–positive gastric MALT lymphoma displays moderate BCL10 nuclear expression. (C) A gastric MALT lymphoma lacking t(11; 18)(q21;q21) shows cytoplasmic BCL10 expression. Original magnification, × 400 for all panels.