Translocations t(14;18)(q32;q21) and t(11;14)(q13;q32) are recurrent findings in follicular lymphoma (FL) and mantle cell lymphoma (MCL), respectively. However, the molecular counterparts of these translocations can only be detected in up to 75% of FL and 50% of MCL cases using routine techniques. To improve the efficiency of detection, we first devised a single-tube multiplex-polymerase chain reaction (PCR) assay with primers located within a conserved immunoglobulin heavy chain (IGH) sequence and 5' to the main breakpoint cluster regions of BCL2 and CCND1. Using this assay in 17 FL and 11 MCL diagnostic DNA samples, we readily identified a BCL2-IGH fusion in 65% of FL patients and a CCND1-IGH fusion in 55% of MCL patients. In the remaining cases, we used long distance inverse-PCR to detect BCL2-IGH and CCND1-IGH fusion genes with different BCL2 and CCND1 breakpoint locations. We found additional translocations in 3 patients (17%) with FL and in 4 patients (36%) with MCL. Taken together, we show that multiplex-PCR combined with long distance inverse-PCR detected a t(14;18) in 82% of FL patients and a t(11;14) in 91% of MCL patients, demonstrating that this 2-step protocol is an effective approach for molecular detection of t(11;14) and t(14;18) in B-cell lymphomas.