Synapse - Neuroendocrine tumours of the breast: A genomic comparison with mucinous breast cancers and neuroendocrine tumours of other anatomic sites

Neuroendocrine tumours of the breast: A genomic comparison with mucinous breast cancers and neuroendocrine tumours of other anatomic sites Journal Article

Authors:	Pareja, F.; Vahdatinia, M.; Marchio, C.; Lee, S. S. K.; Da Cruz Paula, A.; Derakhshan, F.; da Silva, E. M.; Selenica, P.; Dopeso, H.; Chandarlapaty, S.; Wen, H. Y.; Vincent-Salomon, A.; Brogi, E.; Weigelt, B.; Reis-Filho, J. S.
Article Title:	Neuroendocrine tumours of the breast: A genomic comparison with mucinous breast cancers and neuroendocrine tumours of other anatomic sites
Abstract:	Breast neuroendocrine tumours (NETs) constitute a rare histologic subtype of oestrogen receptor (ER)-positive breast cancer, and their definition according to the WHO classification was revised in 2019. Breast NETs display histologic and transcriptomic similarities with mucinous breast carcinomas (MuBCs). Here, we sought to compare the repertoire of genetic alterations in breast NETs with MuBCs and NETs from other anatomic origins. On histologic review applying the new WHO criteria, 18 breast tumours with neuroendocrine differentiation were reclassified as breast NETs (n=10) or other breast cancers with neuroendocrine differentiation (n=8). We reanalysed targeted sequencing or whole-exome sequencing data of breast NETs (n=10), MuBCs type A (n=12) and type B (n=11). Breast NETs and MuBCs were found to be genetically similar, harbouring a lower frequency ofPIK3CAmutations, 1q gains and 16q losses than ER-positive/HER2-negative breast cancers. 3/10 breast NETs harboured the hallmark features of ER-positive disease (ie,PIK3CAmutations and concurrent 1q gains/16q losses). Breast NETs showed an enrichment of oncogenic/likely oncogenic mutations affecting transcription factors compared with common forms of ER-positive breast cancer and with pancreatic and pulmonary NETs. Breast NETs are heterogeneous and are characterised by an enrichment of mutations in transcription factors and likely constitute a spectrum of entities histologically and genomically related to MuBCs. While most breast NETs are distinct from ER-positive/HER2-negative IDC-NSTs, a subset of breast NETs appears to be genetically similar to common forms of ER-positive breast cancer, suggesting that some breast cancers may acquire neuroendocrine differentiation later in tumour evolution. © 2022, BMJ Publishing Group Ltd and Association of Clinical Pathologists. All rights reserved.
Keywords:	clinical article; controlled study; human tissue; gene mutation; somatic mutation; breast cancer; breast; gene frequency; transcription factor; pathology; neuroendocrine tumor; genomics; papillary carcinoma; estrogen receptor; molecular; ductal carcinoma; lobular carcinoma; neuroendocrine tumours; estrogen receptor positive breast cancer; human; female; article; whole exome sequencing; anatomical location; breast neuroendocrine tumor; mucinous breast carcinoma
Journal Title:	Journal of Clinical Pathology
Volume:	75
Issue:	1
ISSN:	0021-9746
Publisher:	BMJ Publishing Group Ltd.
Date Published:	2022-01-01
Start Page:	10
End Page:	17
Language:	English
DOI:	10.1136/jclinpath-2020-207052
PUBMED:	33148628
PROVIDER:	scopus
PMCID:	PMC8260149
DOI/URL:	https://www.scopus.com/inward/record.uri?eid=2-s2.0-85095957494&doi=10.1136%2fjclinpath-2020-207052&partnerID=40&md5=bcc351986d7a076b8d069769f4b4eb91
Notes:	Article -- Export Date: 1 February 2022 -- Source: Scopus