Improvement in the detection rate of t(14;18) translocation on paraffin-embedded tissue: a combination approach using PCR and FISH.
OBJECTIVE
PCR has been the primary method used for the detection of t(14;18) translocation in formalin-fixed, paraffin-embedded tissues. This technique mainly targets the well-characterised breakpoint regions in chromosomes 14 and 18. FISH is now applicable on paraffin tissue sections and has been suggested to be capable of detecting essentially 100% of t(14;18) translocated cases. In this study, we described the application of both PCR and FISH for the detection of t(14;18) translocation.


METHODS
Fifty follicular lymphoma cases were retrieved from the files of the Department of Pathology, University of Malaya Medical Centre (UMMC). Nested PCR amplification of MBR/JH and mcr/JH was performed in these cases, and those cases that did not demonstrate the translocation were subjected to FISH analysis.


RESULTS
Thirty cases (60%) had t(14;18) translocation detected by PCR, 25 (50%) had breakpoint with MBR and five (10%) involved mcr. Twenty cases without detectable t(14;18) translocation by PCR were analysed by FISH. Eleven cases were successfully probed, and four of them showed positive translocation signal.


CONCLUSIONS
The combination of PCR and FISH analysis on paraffin tissue sections for the detection of t(14;18) translocation increases the sensitivity of detection from 60 to 68%. Problems encountered in our FISH analysis on tissue sections impose certain limitations in using this technique for retrospective screening of large number of samples. Therefore, we suggested the application of PCR as the first screening tool on retrospective archival materials, followed by FISH on those PCR-negative cases.
Shaminie
Jairaman
J
Department of Pathology, University of Malaya, Kuala Lumpur, Malaysia.
Peh
Suat Cheng
SC
Tan
Mary Jin Ai
MJ
D043283:Chromosome Fragile Sites; D002883:Chromosomes, Human, Pair 14; D002887:Chromosomes, Human, Pair 18; D017931:DNA Primers / Q000737:chemistry; D004273:DNA, Neoplasm / Q000032:analysis; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008224:Lymphoma, Follicular / Q000235:genetics* / Q000473:pathology; D016612:Paraffin Embedding; D016133:Polymerase Chain Reaction / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014178:Translocation, Genetic
D017931:DNA Primers; D004273:DNA, Neoplasm