The goal of this study was to assess the performance characteristics of the Automated Cellular Imaging System (ACIS III) for HER2 immunohistochemical analysis. The study was performed on 187 biopsy slides from patients who underwent HER2 testing between January and February 2008. Three scoring methods by the ACIS III were compared with the manual score and fluorescence in situ hybridization (FISH) results for HER2 amplification. The equal distribution score (EQD) method, in which 2 areas each of high-, moderate-, and low-intensity staining were measured, most closely matched the FISH HER2 amplification result. The numbers of immunohistochemically negative (0 or 1+)/FISH+ cases were equivalent for all methods. The EQD method had significantly fewer 2+ cases (n = 16) (P < .001) vs the manual method (n = 35) and yielded a higher positive predictive value (38%) for HER2 amplification compared with the manual method (20%). The EQD method may more accurately identify FISH-amplified HER2 cases with fewer 2+ cases that would be "reflexed" to FISH compared with the manual method.
// Ferga C. Gleeson 1 , Sarah E. Kerr 2 , Benjamin R. Kipp 2 , Jesse S. Voss 2 , Douglas M. Minot 2 , Zheng Jin Tu 3 , Michael R. Henry 2 , Rondell P. Graham 2 , George Vasmatzis 4 , John C. Cheville 4 , Konstantinos N. Lazaridis 1, 4 , Michael J. Levy 1 1 Division of Gastroenterology & Hepatology, Mayo Clinic Rochester, MN, USA 2 Department of Laboratory Medicine & Pathology, Mayo Clinic Rochester, MN, USA 3 Division of Biomedical Statics & Informatics, Department of Health Sciences Research, Mayo Clinic Rochester, MN, USA 4 Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA Correspondence to: Ferga C. Gleeson, email: gleeson.ferga@mayo.edu Keywords: endoscopic ultrasound fine needle aspiration, pancreatic adenocarcinoma, targeted next-generation sequencing, mutation concordance, personalized medicine Received: April 04, 2016 Accepted: April 24, 2016 Published: May 18, 2016 ABSTRACT Background & Aims: Less than 10% of registered drug intervention trials for pancreatic ductal adenocarcinoma (PDAC) include a biomarker stratification strategy. The ability to identify distinct mutation subsets via endoscopic ultrasound fine needle aspiration (EUS FNA) molecular cytology could greatly aid clinical trial patient stratification and offer predictive markers. We identified chemotherapy treatment naïve ampullary adenocarcinoma and PDAC patients who underwent EUS FNA to assess multigene mutational frequency and diversity with a surgical resection concordance assessment, where available. Methods: Following strict cytology smear screening criteria, targeted next generation sequencing (NGS) using a 160 cancer gene panel was performed. Results: Complete sequencing was achieved in 29 patients, whereby 83 pathogenic alterations were identified in 21 genes. Cytology genotyping revealed that the majority of mutations were identified in KRAS (93%), TP53 (72%), SMAD4 (31%), and GNAS (10%). There was 100% concordance for the following pathogenic alterations: KRAS, TP53, SMAD4, KMT2D, NOTCH2, MSH2, RB1, SMARCA4, PPP2R1A, PIK3R1, SCL7A8, ATM, and FANCD2. Absolute multigene mutational concordance was 83%. Incremental cytology smear mutations in GRIN2A, GATA3 and KDM6A were identified despite re-examination of raw sequence reads in the corresponding resection specimens. Conclusions: EUS FNA cytology genotyping using a 160 cancer gene NGS panel revealed a broad spectrum of pathogenic alterations. The fidelity of cytology genotyping to that of paired surgical resection specimens suggests that EUS FNA represents a suitable surrogate and may complement the conventional stratification criteria in decision making for therapies and may guide future biomarker driven therapeutic development.
This news section is written by a medical journalist and offers Cancer Cytopathology readers timely information on events, issues, and personalities of interest to the subspecialty.This edition, Part 3 of a 3-part series, examines follow-up care for medical procedures performed abroad and complications that can arise in the aftermath following medical tourism trips.
