Dynamic clonal remodelling in breast cancer metastases is associated with subtype conversion.
Adult
Aged
Aged, 80 and over
Biomarkers, Tumor
/ genetics
Bone Neoplasms
/ genetics
Brain Neoplasms
/ genetics
Breast Neoplasms
/ classification
Female
Follow-Up Studies
Gene Expression Regulation, Neoplastic
High-Throughput Nucleotide Sequencing
Humans
Lymphatic Metastasis
Middle Aged
Mutation
Neoplasm Recurrence, Local
/ genetics
Prognosis
Prospective Studies
Skin Neoplasms
/ genetics
Bioinformatics
Breast cancer
Clinical subtype
Clonal remodelling
Heterogeneity
Intrinsic subtype
PAM50
Journal
European journal of cancer (Oxford, England : 1990)
ISSN: 1879-0852
Titre abrégé: Eur J Cancer
Pays: England
ID NLM: 9005373
Informations de publication
Date de publication:
10 2019
10 2019
Historique:
received:
07
02
2019
revised:
03
07
2019
accepted:
04
07
2019
pubmed:
7
9
2019
medline:
10
6
2020
entrez:
7
9
2019
Statut:
ppublish
Résumé
Changes in the clinical subtype (CS) and intrinsic subtype (IS) between breast cancer (BC) metastases and corresponding primary tumours have been reported. However, their relationship with tumour genomic changes remains poorly characterised. Here, we analysed the association between genomic remodelling and subtype conversion in paired primary and metastatic BC samples. A total of 57 paired primary and metastatic tumours from GEICAM/2009-03 (ConvertHER, NCT01377363) study participants with centrally assessed CS (n = 57) and IS (n = 46) were analysed. Targeted capture and next-generation sequencing of 202 genes on formalin-fixed paraffin-embedded samples was performed. The cancer cell fraction (CCF) of mutations in primary and metastatic pairs was estimated as a surrogate of tumour clonal architecture. Changes in mutation CCF between matched primary and metastatic tumours were analysed in the presence or absence of subtype conversion. CS conversion occurred in 24.6% and IS conversion occurred in 36.9% of metastases. Primary tumours and metastases had a median of 11 (range, 3-29) and 9 (range, 1-38) mutations, respectively (P = 0.05). Overall, mutations in metastases showed a higher estimated CCF than in primary tumours (median CCF, 0.51 and 0.47, respectively; P = 0.042), consistent with increased clonal homogeneity. The increase in mutation CCF was significant in CS-converted (P = 0.04) but not in IS-converted (P = 0.48) metastases. Clonal remodelling was highest in metastases from hormone receptor-positive and human epidermal growth factor 2 (HER2)-positive tumours (P = 0.006). Mutations in BC metastases showed significantly higher estimated CCF than primary tumours. CCF changes were more prominent in metastases with CS conversion. Our findings suggest that changes in BC subtypes are linked to clonal remodelling during BC evolution.
Sections du résumé
BACKGROUND
Changes in the clinical subtype (CS) and intrinsic subtype (IS) between breast cancer (BC) metastases and corresponding primary tumours have been reported. However, their relationship with tumour genomic changes remains poorly characterised. Here, we analysed the association between genomic remodelling and subtype conversion in paired primary and metastatic BC samples.
METHODS
A total of 57 paired primary and metastatic tumours from GEICAM/2009-03 (ConvertHER, NCT01377363) study participants with centrally assessed CS (n = 57) and IS (n = 46) were analysed. Targeted capture and next-generation sequencing of 202 genes on formalin-fixed paraffin-embedded samples was performed. The cancer cell fraction (CCF) of mutations in primary and metastatic pairs was estimated as a surrogate of tumour clonal architecture. Changes in mutation CCF between matched primary and metastatic tumours were analysed in the presence or absence of subtype conversion.
FINDINGS
CS conversion occurred in 24.6% and IS conversion occurred in 36.9% of metastases. Primary tumours and metastases had a median of 11 (range, 3-29) and 9 (range, 1-38) mutations, respectively (P = 0.05). Overall, mutations in metastases showed a higher estimated CCF than in primary tumours (median CCF, 0.51 and 0.47, respectively; P = 0.042), consistent with increased clonal homogeneity. The increase in mutation CCF was significant in CS-converted (P = 0.04) but not in IS-converted (P = 0.48) metastases. Clonal remodelling was highest in metastases from hormone receptor-positive and human epidermal growth factor 2 (HER2)-positive tumours (P = 0.006).
CONCLUSIONS
Mutations in BC metastases showed significantly higher estimated CCF than primary tumours. CCF changes were more prominent in metastases with CS conversion. Our findings suggest that changes in BC subtypes are linked to clonal remodelling during BC evolution.
Identifiants
pubmed: 31491604
pii: S0959-8049(19)30403-4
doi: 10.1016/j.ejca.2019.07.003
pii:
doi:
Substances chimiques
Biomarkers, Tumor
0
Types de publication
Journal Article
Multicenter Study
Observational Study
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
54-64Informations de copyright
Copyright © 2019 Elsevier Ltd. All rights reserved.