PMID- 36077795
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20230308
IS  - 2072-6694 (Print)
IS  - 2072-6694 (Electronic)
IS  - 2072-6694 (Linking)
VI  - 14
IP  - 17
DP  - 2022 Aug 31
TI  - Can HER2 1+ Breast Cancer Be Considered as HER2-Low Tumor? A Comparison of 
      Clinicopathological Features, Quantitative HER2 mRNA Levels, and Prognosis among 
      HER2-Negative Breast Cancer.
LID - 10.3390/cancers14174250 [doi]
LID - 4250
AB  - Background: Human epidermal growth factor receptor 2 (HER2)-low tumor is a new 
      entity defined as HER2 immunohistochemistry (IHC) 1+ or 2+/fluorescence in situ 
      hybridization (FISH)-negative. We aimed to evaluate whether HER2 mRNA levels 
      tested by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) 
      could better define HER2-low tumors. Patients and methods: Consecutive breast 
      cancer patients with hormonal receptor-positive, HER2-negative diseases, and HER2 
      mRNA results were included. Clinicopathologic features, HER2 mRNA expression 
      level, and prognosis were compared among HER2 0, 1+ and 2+/FISH- groups. 
      Concordance of the HER2 category between qRT-PCR and IHC/FISH was analyzed for 
      each group. Results: 2296 patients were included: 368 (16.0%) HER2 0, 911 (39.7%) 
      1+, and 1017 (44.3%) 2+/FISH- tumors. HER2 1+ cases shared similarities with HER2 
      0 tumors in terms of clinicopathologic features (all p > 0.05), whereas IHC 
      2+/FISH- cases were less often non-IDC (p = 0.045), node-negative (p = 0.044), 
      and Ki-67 < 14% (p <0.001). The mRNA expression was similar between HER2 0 and 1+ 
      cases (p = 0.063), and both were lower than 2+/FISH- cases (p < 0.001). A poor 
      concordance rate was found between IHC/FISH and qRT-PCR for HER2 0 and HER2-low 
      cases (Cohen's kappa 0.126, p < 0.001). No survival difference was observed among 
      these groups, whether stratified by HER2 IHC/FISH status or mRNA level (all p > 
      0.05). Conclusions: HER2 1+ cases had similar clinicopathological features to 
      HER2 0 breast cancers, and both were different from HER2 2+/FISH- cases. HER2 
      mRNA levels were comparable between HER2 0 and 1+ tumors, and both were 
      significantly lower than IHC 2+/FISH- tumors. Neither IHC nor qRT-PCR may be 
      optimal to quantify HER2-low expression, especially for HER2 1+ patients.
FAU - Shu, Lan
AU  - Shu L
AD  - Department of General Surgery, Comprehensive Breast Health Center, Ruijin 
      Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025, 
      China.
FAU - Tong, Yiwei
AU  - Tong Y
AUID- ORCID: 0000-0001-5131-9095
AD  - Department of General Surgery, Comprehensive Breast Health Center, Ruijin 
      Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025, 
      China.
FAU - Li, Zhuoxuan
AU  - Li Z
AD  - Department of General Surgery, Comprehensive Breast Health Center, Ruijin 
      Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025, 
      China.
FAU - Chen, Xiaosong
AU  - Chen X
AD  - Department of General Surgery, Comprehensive Breast Health Center, Ruijin 
      Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025, 
      China.
FAU - Shen, Kunwei
AU  - Shen K
AD  - Department of General Surgery, Comprehensive Breast Health Center, Ruijin 
      Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200025, 
      China.
LA  - eng
GR  - 81772797, 82072937/National Natural Science Foundation of China/
GR  - 20172007/Shanghai Municipal Education Commission/
GR  - 21YF1427400/Science and Technology Commission of Shanghai Municipality/
PT  - Journal Article
DEP - 20220831
PL  - Switzerland
TA  - Cancers (Basel)
JT  - Cancers
JID - 101526829
PMC - PMC9455006
OTO - NOTNLM
OT  - HER2-low
OT  - breast cancer
OT  - immunohistochemistry
OT  - mRNA level
OT  - prognosis
COIS- The authors declare no conflict of interest.
EDAT- 2022/09/10 06:00
MHDA- 2022/09/10 06:01
PMCR- 2022/08/31
CRDT- 2022/09/09 01:11
PHST- 2022/08/10 00:00 [received]
PHST- 2022/08/29 00:00 [accepted]
PHST- 2022/09/09 01:11 [entrez]
PHST- 2022/09/10 06:00 [pubmed]
PHST- 2022/09/10 06:01 [medline]
PHST- 2022/08/31 00:00 [pmc-release]
AID - cancers14174250 [pii]
AID - cancers-14-04250 [pii]
AID - 10.3390/cancers14174250 [doi]
PST - epublish
SO  - Cancers (Basel). 2022 Aug 31;14(17):4250. doi: 10.3390/cancers14174250.