Comparison of Alu-PCR, microsatelite instability, and immunohistochemical analyses in finding features characteristic for hereditary nonpolyposis colorectal cancer.
OBJECTIVE
To evaluate and compare alterations detected by Alu-PCR, microsatellite instability (MI), and absence of hMLH1 and hMSH2 protein expression measured by immunohistochemical (IHC) analyses as features characteristic of hereditary nonpolyposis colorectal cancer (HNPCC).


METHODS
Alu-PCR, MI, and IHC analyses were performed in two groups of patients: (A) HNPCC diagnosed definitively or with high probability (11 patients); (B) sporadic late-onset colorectal cancers (15 patients).


RESULTS
Quantitative alterations recorded by Alu-PCR were not characteristic for Lynch syndrome, occurring more frequently in sporadic late-onset CRC (73% in group B vs 45% in group A). Qualitative changes (occurrence of additional peaks or shifts) have been found to be associated with HNPCC with odds ratio (OR) 2.4, specificity approximately 70% and sensitivity approximately 55%. Findings in MI and IHC analyses have been recognized as features more characteristic of HNPCC suggesting Lynch syndrome with OR 4.8, specificity approximately 80%, sensitivity approximately 55% (MI) and OR 8.0, specificity approximately 93%, sensitivity approximately 36% (IHC).


CONCLUSIONS
Molecular techniques allowing identification of patients with a high probability of having HNPCC include IHC and MI analyses. Our results suggest that their replacement by Alu-PCR analysis in diagnosis of HNPCC is not justified.
Debniak
T
T
Department of Genetics and Pathology, Pomeranian Medical University, Poland. debniak@poczta.wp.pl
Gorski
B
B
Cybulski
C
C
Jakubowska
A
A
Kurzawski
G
G
Kladny
J
J
Lubinski
J
J
D048868:Adaptor Proteins, Signal Transducing; D020087:Alu Elements / Q000235:genetics*; D002352:Carrier Proteins; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism*; D004268:DNA-Binding Proteins; D003937:Diagnosis, Differential; D018095:Germ-Line Mutation; D006801:Humans; D007150:Immunohistochemistry; D018895:Microsatellite Repeats / Q000235:genetics*; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C501486:MLH1 protein, human; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; C497172:MSH2 protein, human; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein