PMID- 37554155 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20230810 IS - 1179-1314 (Print) IS - 1179-1314 (Electronic) IS - 1179-1314 (Linking) VI - 15 DP - 2023 TI - Invasive Breast Cancer with HER2 >/=4.0 and <6.0: Risk Classification and Molecular Typing by a 21-Gene Expression Assay and MammaPrint Plus BluePrint Testing. PG - 563-575 LID - 10.2147/BCTT.S420738 [doi] AB - PURPOSE: To investigate the HER2 status and clinicopathological features in invasive breast cancer with HER2 >/=4.0 and <6.0, which has always been controversial. METHODS: Forty breast cancer cases with HER2 >/=4.0 and <6.0 by fluorescence in situ hybridization (FISH) were collected and classified into two groups based on the HRE2/CEP17 ratio (Group A: >/=2.0, n=22; Group B: <2.0, n=18). Clinicopathological characteristics, HER2 status, risk classification, and molecular typing were further analyzed and compared by 21-Gene expression assay and MammaPrint plus BluePrint test. RESULTS: The majority of cases in both groups were invasive carcinoma (NOS), with histological grade II, HR+, Ki-67 >/=20%, HER2 2+, and a high risk of recurrence, although younger patients and lymph node metastases were more common in Group A. Surprisingly, all HR+ breast cancers in both groups were classified as luminal-type, HR- cases were all basal-type or unknown, and the index of HER2 in all cases was <0.000 using the BluePrint test, which indicated that HER2 status should be negative. Furthermore, the level of HER2 mRNA expression in all cases of both groups was <10.7, which was defined as HER2 negative by the 21-Gene expression assay. In addition, 10 patients of Group A received anti-HER2 neoadjuvant therapy; only one patient with HR- achieved Grade 5 based on the Miller-Payne system, whereas none of the patients achieved pathological complete response (pCR) based on the Residual Cancer Burden system. CONCLUSION: Group A breast cancer, which has always been unquestionably diagnosed as HER2 amplification, was more likely to be HER2 negative and derived less benefit from anti-HER2 neoadjuvant chemotherapy. Group A breast cancer should be distinguished from classical HER2-positive breast cancers when assessing HER2 FISH, and a larger cohort of Group A patients should be included in further studies. CI - (c) 2023 Bai et al. FAU - Bai, Qianming AU - Bai Q AUID- ORCID: 0000-0003-0657-9845 AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Lv, Hong AU - Lv H AUID- ORCID: 0000-0002-2129-2781 AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Bao, Longlong AU - Bao L AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Yang, Yu AU - Yang Y AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Zhang, Xin AU - Zhang X AD - Department of Pathology, Fudan University Zhongshan Hospital, Shanghai, 200032, People's Republic of China. FAU - Chang, Heng AU - Chang H AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Xue, Tian AU - Xue T AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Ren, Min AU - Ren M AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Zhu, Xiaoli AU - Zhu X AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Zhou, Xiaoyan AU - Zhou X AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. FAU - Yang, Wentao AU - Yang W AD - Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, People's Republic of China. AD - Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, People's Republic of China. AD - Institute of Pathology, Fudan University, Shanghai, 200032, People's Republic of China. LA - eng PT - Journal Article DEP - 20230803 PL - New Zealand TA - Breast Cancer (Dove Med Press) JT - Breast cancer (Dove Medical Press) JID - 101591856 PMC - PMC10406110 OTO - NOTNLM OT - 21-gene expression assay OT - FISH OT - HER2 OT - MammaPrint plus BluePrint OT - breast cancer COIS- The authors declare no conflicts of interest in this work. EDAT- 2023/08/09 06:43 MHDA- 2023/08/09 06:44 PMCR- 2023/08/03 CRDT- 2023/08/09 03:54 PHST- 2023/05/24 00:00 [received] PHST- 2023/07/26 00:00 [accepted] PHST- 2023/08/09 06:44 [medline] PHST- 2023/08/09 06:43 [pubmed] PHST- 2023/08/09 03:54 [entrez] PHST- 2023/08/03 00:00 [pmc-release] AID - 420738 [pii] AID - 10.2147/BCTT.S420738 [doi] PST - epublish SO - Breast Cancer (Dove Med Press). 2023 Aug 3;15:563-575. doi: 10.2147/BCTT.S420738. eCollection 2023.