Translocations t(11;18)(q21;q21) and t(14;18)(q32;q21) are the main chromosomal abnormalities involving MLT/MALT1 in MALT lymphomas

Leukemia. 2003 Nov;17(11):2225-9. doi: 10.1038/sj.leu.2403122.


The recently discovered MLT/MALT1 gene is fused with the API2 gene in the t(11;18)(q21;q21), which characterizes about one-third of MALT lymphomas. In order to screen for variant translocations and amplifications of MLT/MALT1, we have developed a novel, undirected two-color interphase fluorescence in situ hybridization (FISH) assay with two PAC clones flanking MLT/MALT1. This assay was applied to 108 marginal zone B-cell lymphomas (MZBCLs), including 72 extranodal MALT lymphomas, 17 nodal, and 19 splenic MZBCL. In 19 MALT lymphomas (26%), but in none of the nodal or splenic MZBCL, separated hybridization signals of the MLT/MALT1 flanking probes, were found. Further FISH analyses showed that 12 of these 19 cases displayed the classical t(11;18) and the remaining seven cases revealed the novel t(14;18)(q32;q21), involving the MLT/MALT1 and IGH genes. The frequency at which these translocations occurred varied significantly with the primary location of disease. The t(11;18) was mainly detected in gastrointestinal MALT lymphomas, whereas the t(14;18) occurred in MALT lymphomas of the parotid gland and the conjunctiva. Amplification of MLT/MALT1 was not observed in any of the lymphomas analyzed. We conclude that the translocations t(11;18)(q21;q21) and t(14;18)(q21;q32) represent the main structural aberrations involving MLT/MALT1 in MALT lymphomas, whereas true amplifications of MLT/MALT1 occur rarely in MZBCL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / pathology
  • Caspases
  • Chromosome Aberrations*
  • Chromosome Mapping
  • Chromosomes, Human, Pair 11*
  • Chromosomes, Human, Pair 14*
  • Chromosomes, Human, Pair 18*
  • Gastrointestinal Neoplasms / genetics
  • Humans
  • In Situ Hybridization, Fluorescence
  • Lymphoma, B-Cell, Marginal Zone / genetics*
  • Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein
  • Neoplasm Proteins / genetics*
  • Parotid Neoplasms / genetics
  • Proteins / genetics*
  • Retrospective Studies
  • Stomach Neoplasms / genetics
  • Translocation, Genetic*


  • Neoplasm Proteins
  • Proteins
  • Caspases
  • MALT1 protein, human
  • Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein