TY - JOUR
T1 - IgH PCR of zinc formalin-fixed, paraffin-embedded non-lymphomatous gastric samples produces artifactual "clonal" bands not observed in paired tissues unexposed to zinc formalin
AU - Ahrens, Kim
AU - Braylan, Raul
AU - Almasri, Nidal
AU - Foss, Robin
AU - Rimsza, Lisa
PY - 2002/8
Y1 - 2002/8
N2 - Helicobacter pylori (HP) causes dense gastritis that can be difficult to distinguish morphologically from MALT-type lymphoma (ML). Immunoglobulin heavy chain (IgH) gene analysis by polymerase chain reaction (PCR) is often used to resolve diagnosis. However, monoclonal bands have been reported in nonmalignant cases of gastritis. Retrospectively, 16 gastric ML with both formalin-fixed, paraffin-embedded (FF-PE) and ethanol-fixed samples (EF), and 9 cases of FF-PE HP-gastritis were analyzed by IgH PCR to document the presence of non-reproducible bands in HP-gastritis, but not ML samples. In duplicate analyses, 12 of 16 ML yielded identical monoclonal bands in FF-PE and EF samples whereas 3 of 9 FF-PE gastritis cases yielded different-sized (ie, non-reproducible) "clonal" bands. Sequencing of two PCR products from a gastritis case confirmed IgH gene sequences. To investigate whether FF-PE had a direct effect on producing these non-reproducible bands, 7 gastrectomy samples were prospectively divided into EF and FF-PE halves for IgH PCR. All 7 samples demonstrated polyclonal smears in EF portions while 4 of 7 FF-PE portions yielded either multiple distinct bands or non-reproducible bands. In conclusion, IgH PCR of FF-PE tissue can create artifactual "clonal" bands, which are the appropriate product size, contain IgH sequences, and if not performed in duplicate, may confuse interpretation of B-cell clonality.
AB - Helicobacter pylori (HP) causes dense gastritis that can be difficult to distinguish morphologically from MALT-type lymphoma (ML). Immunoglobulin heavy chain (IgH) gene analysis by polymerase chain reaction (PCR) is often used to resolve diagnosis. However, monoclonal bands have been reported in nonmalignant cases of gastritis. Retrospectively, 16 gastric ML with both formalin-fixed, paraffin-embedded (FF-PE) and ethanol-fixed samples (EF), and 9 cases of FF-PE HP-gastritis were analyzed by IgH PCR to document the presence of non-reproducible bands in HP-gastritis, but not ML samples. In duplicate analyses, 12 of 16 ML yielded identical monoclonal bands in FF-PE and EF samples whereas 3 of 9 FF-PE gastritis cases yielded different-sized (ie, non-reproducible) "clonal" bands. Sequencing of two PCR products from a gastritis case confirmed IgH gene sequences. To investigate whether FF-PE had a direct effect on producing these non-reproducible bands, 7 gastrectomy samples were prospectively divided into EF and FF-PE halves for IgH PCR. All 7 samples demonstrated polyclonal smears in EF portions while 4 of 7 FF-PE portions yielded either multiple distinct bands or non-reproducible bands. In conclusion, IgH PCR of FF-PE tissue can create artifactual "clonal" bands, which are the appropriate product size, contain IgH sequences, and if not performed in duplicate, may confuse interpretation of B-cell clonality.
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U2 - 10.1016/S1525-1578(10)60697-6
DO - 10.1016/S1525-1578(10)60697-6
M3 - Article
C2 - 12169677
AN - SCOPUS:0036667667
SN - 1525-1578
VL - 4
SP - 159
EP - 163
JO - Journal of Molecular Diagnostics
JF - Journal of Molecular Diagnostics
IS - 3
ER -