PMID- 36878823
OWN - NLM
STAT- MEDLINE
DCOM- 20230529
LR  - 20230622
IS  - 1938-0666 (Electronic)
IS  - 1526-8209 (Linking)
VI  - 23
IP  - 4
DP  - 2023 Jun
TI  - Breast Cancer With a HER2 FISH Group 2 Result: Should HER2 Tests be Repeated?
PG  - 415-422
LID - S1526-8209(23)00037-X [pii]
LID - 10.1016/j.clbc.2023.02.006 [doi]
AB  - BACKGROUND: Breast cancer with fluorescence in situ hybridization (FISH) group 2 
      pattern (HER2 <4 and HER2/CEP17 ratio >/=2, a subset of monosomy CEP17) was 
      historically considered HER2-positive, but mostly HER2-negative according to 
      updated 2018 American Society of Clinical Oncology (ASCO)/College of American 
      Pathologists (CAP) guidelines unless 3+ by immunohistochemistry (IHC). 
      Therapeutic relevance of this group remained elusive, therefore we assessed if 
      repeat IHC and FISH can assist final HER2 classification. PATIENT AND METHODS: We 
      retrospectively reviewed HER2 FISH performed at our institution from 2014 to 2018 
      and identified 23 of 3554 (0.6%) breast cancer cases with at least one-time 
      measurement of HER2 FISH categorized as group 2. Repeat HER2 tests were performed 
      for cases with available alternative tumor samples and compared with initial 
      testing following 2018 ASCO/CAP guidelines. RESULTS: Only 1 of 23 group 2 cases 
      was HER2-positive, 0/18 in primary and 1/5 in metastatic/recurrent tumors. Of 13 
      primary tumors with repeat HER2 results; 10 (77%) remained HER2-negative; 3 (23%) 
      changed from HER2-negative (group 2 and IHC 2+) to HER2-positive (group 1 and IHC 
      2+). Among 8 of these 13 patients receiving neoadjuvant systemic therapy 
      containing anti-HER2 agent, 3 (38%) achieved pathologic complete response (pCR). 
      Two of 3 pCR cases were HER2-positive converters on repeat testing. Three pCR 
      cases were ER-negative or -low positive and Ki67 >/=40%, while 5 partial responders 
      were ER-positive and Ki67 <40% (P < .05). CONCLUSION: Breast cancer with HER2 
      FISH group 2 result may represent heterogeneous populations of tumor cells being 
      originated de novo or preferentially selected secondary to therapy. Repeat HER2 
      tests on alternative samples may be considered to guide anti-HER2 therapy.
CI  - Copyright (c) 2023 Elsevier Inc. All rights reserved.
FAU - Wang, Minhua
AU  - Wang M
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Ding, Qingqing
AU  - Ding Q
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Gu, Jun
AU  - Gu J
AD  - The University of Texas MD Anderson Cancer Center, School of Health Professions, 
      Houston, TX.
FAU - Sfamenos, Steven M
AU  - Sfamenos SM
AD  - The University of Texas MD Anderson Cancer Center, School of Health Professions, 
      Houston, TX.
FAU - Huo, Lei
AU  - Huo L
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Tang, Zhenya
AU  - Tang Z
AD  - Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Sun, Hongxia
AU  - Sun H
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Robinson, Melissa
AU  - Robinson M
AD  - Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Tang, Guilin
AU  - Tang G
AD  - Department of Hematopathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Lim, Bora
AU  - Lim B
AD  - Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer 
      Center, Houston, TX.
FAU - Wu, Yun
AU  - Wu Y
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Albarracin, Constance T
AU  - Albarracin CT
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Sahin, Aysegul A
AU  - Sahin AA
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX.
FAU - Chen, Hui
AU  - Chen H
AD  - Department of Pathology, The University of Texas MD Anderson Cancer Center, 
      Houston, TX. Electronic address: hchen7@mdanderson.org.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20230212
PL  - United States
TA  - Clin Breast Cancer
JT  - Clinical breast cancer
JID - 100898731
RN  - EC 2.7.10.1 (Receptor, ErbB-2)
RN  - 0 (Ki-67 Antigen)
RN  - 0 (Biomarkers, Tumor)
SB  - IM
MH  - Humans
MH  - Female
MH  - *Breast Neoplasms/genetics/therapy/pathology
MH  - In Situ Hybridization, Fluorescence/methods
MH  - Receptor, ErbB-2/genetics/analysis
MH  - Retrospective Studies
MH  - Ki-67 Antigen
MH  - Neoplasm Recurrence, Local/genetics
MH  - Biomarkers, Tumor/genetics/analysis
OTO - NOTNLM
OT  - ASCO/CAP guidelines
OT  - FISH
OT  - HER2 amplification
OT  - Monosomy CEP17
OT  - heterogeneity
COIS- Disclosure All authors declare they have no conflicts of interest.
EDAT- 2023/03/07 06:00
MHDA- 2023/05/29 06:42
CRDT- 2023/03/06 22:01
PHST- 2022/12/21 00:00 [received]
PHST- 2023/02/08 00:00 [revised]
PHST- 2023/02/09 00:00 [accepted]
PHST- 2023/05/29 06:42 [medline]
PHST- 2023/03/07 06:00 [pubmed]
PHST- 2023/03/06 22:01 [entrez]
AID - S1526-8209(23)00037-X [pii]
AID - 10.1016/j.clbc.2023.02.006 [doi]
PST - ppublish
SO  - Clin Breast Cancer. 2023 Jun;23(4):415-422. doi: 10.1016/j.clbc.2023.02.006. Epub 
      2023 Feb 12.