PMID- 33942843
OWN - NLM
STAT- MEDLINE
DCOM- 20211109
LR  - 20211109
IS  - 1943-7722 (Electronic)
IS  - 0002-9173 (Linking)
VI  - 156
IP  - 5
DP  - 2021 Oct 13
TI  - Detailed Reanalysis of 500 Breast Cancers With Equivocal HER2 
      Immunohistochemistry and Borderline ERBB2 Fluorescence In Situ Hybridization 
      Results.
PG  - 886-894
LID - 10.1093/ajcp/aqab042 [doi]
AB  - OBJECTIVES: We investigated the impact of our laboratory's reflex testing process 
      for resolving ERBB2 (HER2) status on breast cancer samples that require 
      additional workup after fluorescence in situ hybridization (FISH), per guideline 
      recommendations published in 2018 by the American Society of Clinical Oncology 
      (ASCO) and the College of American Pathologists (CAP). METHODS: In total, 500 
      breast cancer specimens with ERBB2 FISH results in groups 2 through 4 (all 
      reported as immunohistochemistry [IHC] equivocal [2+] at external laboratories) 
      were resubmitted for IHC testing in our laboratory. Per the ASCO/CAP guideline, 
      FISH was rescored when internal IHC was also equivocal (2+), targeted to tumor 
      areas demonstrating more intense IHC staining, if observed. RESULTS: Reflex 
      IHC/FISH testing changed the final reported ERBB2 status in 185 of 500 (37.0%) 
      samples. Result changes included discordant IHC (n = 4 score 0, n = 132 score 1+, 
      and n = 16 score 3+) and discordant FISH (n = 33). Numerical differences in FISH 
      scores were comparable for targeted vs nontargeted FISH rescoring (P = .086 for 
      ERBB2 copy number; P = .49 for ERBB2 ratio). Two cases showed larger differences 
      in FISH scores, suggesting heterogeneity. CONCLUSIONS: Retesting of breast cancer 
      samples with equivocal IHC frequently changes IHC results, but targeted 
      reanalysis of borderline FISH results rarely identifies significant differences 
      in ERBB2 copy number or ratio.
CI  - (c) American Society for Clinical Pathology, 2021. All rights reserved. For 
      permissions, please e-mail: journals.permissions@oup.com.
FAU - Geiersbach, Katherine B
AU  - Geiersbach KB
AUID- ORCID: 0000-0003-0424-7572
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Sill, Daniel R
AU  - Sill DR
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Del Rosario, Kristina M
AU  - Del Rosario KM
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Meyer, Reid G
AU  - Meyer RG
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Spears, Grant M
AU  - Spears GM
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Yuhas, Jason A
AU  - Yuhas JA
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Sukov, William R
AU  - Sukov WR
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Jenkins, Robert B
AU  - Jenkins RB
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Ocal, Idris T
AU  - Ocal IT
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Scottsdale, AZ, 
      USA.
FAU - Mounajjed, Taofic
AU  - Mounajjed T
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Chen, Beiyun
AU  - Chen B
AD  - Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
LA  - eng
PT  - Journal Article
PL  - England
TA  - Am J Clin Pathol
JT  - American journal of clinical pathology
JID - 0370470
RN  - 0 (Biomarkers, Tumor)
RN  - EC 2.7.10.1 (ERBB2 protein, human)
RN  - EC 2.7.10.1 (Receptor, ErbB-2)
SB  - IM
MH  - Adult
MH  - Aged
MH  - Biomarkers, Tumor/*analysis
MH  - *Breast Neoplasms/genetics/metabolism
MH  - Female
MH  - Humans
MH  - Immunohistochemistry/*methods
MH  - In Situ Hybridization, Fluorescence/*methods
MH  - Middle Aged
MH  - Receptor, ErbB-2/*analysis
OTO - NOTNLM
OT  - Breast cancer
OT  - FISH
OT  - HER2
OT  - Image analysis
OT  - Immunohistochemistry
EDAT- 2021/05/05 06:00
MHDA- 2021/11/10 06:00
CRDT- 2021/05/04 08:45
PHST- 2021/05/05 06:00 [pubmed]
PHST- 2021/11/10 06:00 [medline]
PHST- 2021/05/04 08:45 [entrez]
AID - 6263677 [pii]
AID - 10.1093/ajcp/aqab042 [doi]
PST - ppublish
SO  - Am J Clin Pathol. 2021 Oct 13;156(5):886-894. doi: 10.1093/ajcp/aqab042.