ESR1 Mutations in Circulating Plasma Tumor DNA from Metastatic Breast Cancer Patients.
OBJECTIVE
Mutations in the estrogen receptor (ER)α gene, ESR1, have been identified in breast cancer metastases after progression on endocrine therapies. Because of limitations of metastatic biopsies, the reported frequency of ESR1 mutations may be underestimated. Here, we show a high frequency of ESR1 mutations using circulating plasma tumor DNA (ptDNA) from patients with metastatic breast cancer.


METHODS
We retrospectively obtained plasma samples from eight patients with known ESR1 mutations and three patients with wild-type ESR1 identified by next-generation sequencing (NGS) of biopsied metastatic tissues. Three common ESR1 mutations were queried for using droplet digital PCR (ddPCR). In a prospective cohort, metastatic tissue and plasma were collected contemporaneously from eight ER-positive and four ER-negative patients. Tissue biopsies were sequenced by NGS, and ptDNA ESR1 mutations were analyzed by ddPCR.


RESULTS
In the retrospective cohort, all corresponding mutations were detected in ptDNA, with two patients harboring additional ESR1 mutations not present in their metastatic tissues. In the prospective cohort, three ER-positive patients did not have adequate tissue for NGS, and no ESR1 mutations were identified in tissue biopsies from the other nine patients. In contrast, ddPCR detected seven ptDNA ESR1 mutations in 6 of 12 patients (50%).


CONCLUSIONS
We show that ESR1 mutations can occur at a high frequency and suggest that blood can be used to identify additional mutations not found by sequencing of a single metastatic lesion.
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
David
D
Chu
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Costanza
C
Paoletti
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Christina
C
Gersch
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Dustin A
DA
VanDenBerg
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Daniel J
DJ
Zabransky
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Rory L
RL
Cochran
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Hong Yuen
HY
Wong
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Patricia Valda
PV
Toro
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Justin
J
Cidado
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Sarah
S
Croessmann
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Bracha
B
Erlanger
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Karen
K
Cravero
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Kelly
K
Kyker-Snowman
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Berry
B
Button
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Heather A
HA
Parsons
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
W Brian
WB
Dalton
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Riaz
R
Gillani
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Arielle
A
Medford
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Kimberly
K
Aung
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Nahomi
N
Tokudome
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Arul M
AM
Chinnaiyan
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Anne
A
Schott
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Dan
D
Robinson
Comprehensive Cancer Centers of Nevada, Las Vegas, Nevada.
Karen S
KS
Jacks
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Josh
J
Lauring
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
Paula J
PJ
Hurley
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan.
Daniel F
DF
Hayes
The University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan. bpark2@jhmi.edu jimmyrae@umich.edu.
James M
JM
Rae
The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland. The Whiting School of Engineering, Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, Maryland. bpark2@jhmi.edu jimmyrae@umich.edu.
Ben Ho
BH
Park
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000097:blood / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000097:blood* / Q000235:genetics; D047628:Estrogen Receptor alpha / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D006801:Humans; D008113:Liver Neoplasms / Q000097:blood / Q000235:genetics* / Q000556:secondary; D008875:Middle Aged; D020125:Mutation, Missense
D004273:DNA, Neoplasm; C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha