[Dual-color silver-enhanced in-situ hybridization for determination of HER2 gene amplification in gastric carcinoma].
OBJECTIVE
To investigate the concordance of dual-color silver enhanced in-situ hybridization (DSISH) and immunohistochemistry (IHC) in the detection of HER2 gene amplification and expression and to evaluate the values of DSISH in detecting HER2 gene status in gastric carcinoma.


METHODS
By using automated DSISH and IHC, HER2 gene status was detected in 230 cases of gastric cancer.


RESULTS
Among the 230 cases of gastric carcinoma tested by DSISH, 43 cases were positive and 187 cases were negative; HER2 gene amplification rate was 18.7% (43/230). The expression of HER2 protein was negative, weakly, moderately and strongly positive in 115, 69, 15 and 31 cases, respectively, by IHC. HER2 protein positive rate was 13.5% (31/230). Of the 43 HER2 gene amplification cases by DSISH, 2, 10, 2 and 29 cases were negative, weakly, moderately and strongly positive by IHC; Of the 187 HER2 negative cases by DSISH, 113, 59, 13 and 2 cases were negative, weakly, moderately and strongly positive by IHC, respectively. The overall concordance of HER2 status in the investigation between IHC and DSIDH was 93.5% (201/215), with a high consistency (Kappa coefficient 0.767, P < 0.01).


CONCLUSIONS
DSISH can be applied to detect the HER2 gene status in gastric cancer and it also has a high consistency with the result of IHC. In addition, due to frequent heterogeneous expression of HER2, cases with moderate HER2 protein expression may need further assessment by DSISH.
Department of Pathology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, China.
Daming
D
Fan
Department of Pathology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, China. E-mail: liyujun.66@163.com.
Yujun
Y
Li
Department of Pathology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, China.
Wenwen
W
Ran
Department of Pathology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, China.
Wenjuan
W
Yu
Department of Pathology, Affiliated Hospital of Qingdao University Medical College, Qingdao 266003, China.
Hong
H
Li
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004943:Esophagogastric Junction; D005260:Female; D005784:Gene Amplification; D018734:Genes, erbB-2; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization / Q000379:methods*; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008869:Microtubule-Associated Proteins; D008875:Middle Aged; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D011123:Polyploidy; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D016622:Silver Staining; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism
D008869:Microtubule-Associated Proteins; D010750:Phosphoproteins; D018719:Erb-b2 Receptor Tyrosine Kinases; C502822:Cep170 protein, human; C508053:ERBB2 protein, human