Similarly, while only small intronic deletions were detected in the API2 and/or the MALT1 gene in three t(11;18)(q21;q21)-positive MALT lymphoma cases with expression of MALT1-API2, the failure to amplify a MALT1-API2 transcript in two other cases correlated with a deletion of a substantial part of 3′-API2 on der(18) ([35] and Baens, unpublished results). This evidence concerns the gene MALT1 and MALT lymphoma.