TP53BP1 and MALT lymphoma: Although there was no significant difference between 53BP1 expression in MALT lymphoma and BLs, we found a correlation between the high frequency of the abnormal type (more than 33.6%, cut-off value to diagnose small B-cell MLs) and t(11;18)(q21;q21)/trisomy of 18q21 (p = 0.0145).