TY - JOUR
T1 - ALK status testing in non-small cell lung carcinoma
T2 - Correlation between ultrasensitive IHC and FISH
AU - Minca, Eugen C.
AU - Portier, Bryce P.
AU - Wang, Zhen
AU - Lanigan, Christopher
AU - Farver, Carol F.
AU - Feng, Yan
AU - Ma, Patrick C.
AU - Arrossi, Valeria A.
AU - Pennell, Nathan A.
AU - Tubbs, Raymond R.
N1 - Funding Information:
Supported in part by a grant from Ventana Medical Systems , which provided partial salary support for the project.
PY - 2013/5
Y1 - 2013/5
N2 - ALK gene rearrangements in advanced non-small cell lung carcinomas (NSCLC) are an indication for targeted therapy with crizotinib. Fluorescence in situ hybridization (FISH) using a recently approved companion in vitro diagnostic class FISH system commonly assesses ALK status. More accessible IHC is challenged by low expression of ALK-fusion transcripts in NSCLC. We compared ultrasensitive automated IHC with FISH for detecting ALK status on 318 FFPE and 40 matched ThinPrep specimens from 296 patients with advanced NSCLC. IHC was concordant with FFPE-FISH on 229 of 231 dual-informative samples (31 positive and 198 negative) and with ThinPrep-FISH on 34 of 34 samples (5 positive and 29 negative). Two cases with negative IHC and borderline-positive FFPE-FISH (15% and 18%, respectively) were reclassified as concordant based on negative matched ThinPrep-FISH and clinical data consistent with ALK-negative status. Overall, after including ThinPrep-FISH and amending the false-positive FFPE-FISH results, IHC demonstrated 100% sensitivity and specificity (95% CI, 0.86 to 1.00 and 0.97 to 1.00, respectively) for ALK detection on 249 dual-informative NSCLC samples. IHC was informative on significantly more samples than FFPE-FISH, revealing additional ALK-positive cases. The high concordance with FISH warrants IHC's routine use as the initial component of an algorithmic approach to clinical ALK testing in NSCLC, followed by reflex FISH confirmation of IHC-positive cases.
AB - ALK gene rearrangements in advanced non-small cell lung carcinomas (NSCLC) are an indication for targeted therapy with crizotinib. Fluorescence in situ hybridization (FISH) using a recently approved companion in vitro diagnostic class FISH system commonly assesses ALK status. More accessible IHC is challenged by low expression of ALK-fusion transcripts in NSCLC. We compared ultrasensitive automated IHC with FISH for detecting ALK status on 318 FFPE and 40 matched ThinPrep specimens from 296 patients with advanced NSCLC. IHC was concordant with FFPE-FISH on 229 of 231 dual-informative samples (31 positive and 198 negative) and with ThinPrep-FISH on 34 of 34 samples (5 positive and 29 negative). Two cases with negative IHC and borderline-positive FFPE-FISH (15% and 18%, respectively) were reclassified as concordant based on negative matched ThinPrep-FISH and clinical data consistent with ALK-negative status. Overall, after including ThinPrep-FISH and amending the false-positive FFPE-FISH results, IHC demonstrated 100% sensitivity and specificity (95% CI, 0.86 to 1.00 and 0.97 to 1.00, respectively) for ALK detection on 249 dual-informative NSCLC samples. IHC was informative on significantly more samples than FFPE-FISH, revealing additional ALK-positive cases. The high concordance with FISH warrants IHC's routine use as the initial component of an algorithmic approach to clinical ALK testing in NSCLC, followed by reflex FISH confirmation of IHC-positive cases.
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U2 - 10.1016/j.jmoldx.2013.01.004
DO - 10.1016/j.jmoldx.2013.01.004
M3 - Article
C2 - 23499337
AN - SCOPUS:84876482049
SN - 1525-1578
VL - 15
SP - 341
EP - 346
JO - Journal of Molecular Diagnostics
JF - Journal of Molecular Diagnostics
IS - 3
ER -