Automated processing of fluorescence in-situ hybridization slides for HER2 testing in breast and gastro-esophageal carcinomas.

[esophageal carcinoma]

HER 2 fluorescence in -situ hybridization (FISH ) is used in breast and gastro-esophageal carcinoma for determining HER 2 gene amplification and patients ' eligibility for HER 2 targeted therapeutics . Traditional manual processing of the FISH slides is labor intensive because of multiple steps that require hands on manipulation of the slides and specifically timed intervals between steps . This highly manual processing also introduces inter-run and inter-operator variability that may affect the quality of the FISH result . Therefore , we sought to incorporate an automated processing instrument into our FISH workflow .Twenty -six cases including breast (20 ) and gastro-esophageal (6 ) cancer comprising 23 biopsies and three excision specimens were tested for HER 2 FISH (Pathvysion , Abbott ) using the Thermobrite Elite (TBE ) system (Leica ). Up to 12 slides can be run simultaneously . All cases were previously tested by the Pathvysion HER 2 FISH assay with manual preparation . Twenty cells were counted by two observers for each case ; five cases were tested on three separate runs by different operators to evaluate the precision and inter-operator variability .There was 100 % concordance in the scoring between the manual and TBE methods as well as among the five cases that were tested on three runs . Only one case failed due to poor probe hybridization . In total , seven cases were positive for HER 2 amplification (HER 2 :CEP 17 ratio >2 .2 ) and the remaining 19 were negative (HER 2 :CEP 17 ratio <1 .8 ) utilizing the 2007 ASCO /CAP scoring criteria . Due to the automated denaturation and hybridization , for each run , there was a reduction in labor of 3 .5 h which could then be dedicated to other lab functions .The TBE is a walk away pre- and post-hybridization system that automates FISH slide processing , improves work flow and consistency and saves approximately 3 .5 h of technologist time . The instrument has a small footprint thus occupying minimal counter space . TBE processed slides performed exceptionally well in comparison to the manual technique with no disagreement in HER 2 amplification status .