Molecular methods for detecting t(11;14) translocations in mantle-cell lymphomas

The t(11;14)(q13;q32) and its molecular counterpart, bc11/JH, are characteristic of mantle-cell lymphomas (MCL). Molecular detection of the translocation is useful in diagnosis and classification, and also shows promise in detecting minimal residual disease. The purpose of this study was to determine the frequency of detecting bc11/JH by polymerase chain reaction (PCR) compared with Southern blot analysis in cases proven by cytogenetic analysis to harbor t(11;14). Southern blot analysis using two probes targeting the major translocation cluster (MTC) and a third probe targeting the p94 region was performed, along with PCR using two different bc11 MTC primers, on 18 cases of MCL known to have t(11;14). Southern blot analysis revealed bc11 rearrangement in 13 of 18 cases (72%), 12 with MTC breakpoints and 1 with a p94 breakpoint. The 2.1-kb MTC probe 'b' was superior to the smaller 700-bp probe 'a' in detecting these rearrangements. The MTC translocation was identified by PCR in 10 of 12 cases, and both primer sets that were tested performed equally well. This study illustrates the frequency with which molecular methods detect known t(11;14) translocations in MCLs. These results may help clinical laboratory scientists optimize their procedure for detecting bc11 translocations by molecular methods at initial diagnosis and for purposes of detecting minimal residual disease.