Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23

Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care

4020 - Genetic Alterations of Early-Stage Breast Cancers by next-generation sequencing (NGS)

Date

22 Oct 2018

Session

Poster display session: Breast cancer - early stage, locally advanced & metastatic, CNS tumours, Developmental therapeutics, Genitourinary tumours - prostate & non-prostate, Palliative care, Psycho-oncology, Public health policy, Sarcoma, Supportive care

Presenters

Yan Xu

Citation

Annals of Oncology (2018) 29 (suppl_8): viii58-viii86. 10.1093/annonc/mdy270

Authors

Y. Xu1, M. Zhang2, R. Chen2, X. Xia2

Author affiliations

  • 1 General Surgical Department, Daping Hospital of Chongqing, 400042 - Chongqing/CN
  • 2 Medical Center, Geneplus-Beijing Institute, 102200 - Beijing/CN
More

Resources

Abstract 4020

Background

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death in women. Patients diagnosed with early stage generally have better survival. However, disease free survival differed significantly for different molecular subtypes. Understanding the genetic alterations of early-stage breast cancer may help to identify patients at high risk for relapse.

Methods

We retrospectively reviewed genetic profiling of 53 early-stage breast cancer samples in our institute. Surgical specimens were analyzed using hybridization capture-based NGS ER-seq method, white blood cells as control, which enables simultaneously assess single-nucleotide variants (SNV), insertions/deletions (indel), rearrangements and somatic copy-number variation(CNV) of 1021 genes.

Results

Fifty-three surgical specimens from 51 female patients with early-stage breast cancer were analyzed, including two bilateral primary breast cancers with different molecular subtypes. There were 29 HR+/HER2-, 6 HER2+, 6 HR+/HER2+ and 12 TNBC. The median diagnosis age was 43(range 31-67). In addition to TP53, there were 16 genes carried actionable mutations identified (details in table). The most frequently mutant genes were TP53 and PIK3CA, in all molecular subtypes. Among PIK3CA mutations, the H1047R/L were tested in all subtypes. Other gene alterations were highly heterogeneous in different molecular subtypes. HRAS or KRAS mutation was always identified with other genes. For instance, HRAS/PIK3CA and KRAS/AKT1 concurrent in 2 HR+/HER2-, KRAS/PIK3CA concurrent in 1 TNBC. Interestingly, for the two bilateral primary breast cancers, one patient had no overlapping mutation in 2 samples within total 6 variants, the other one only had common HER2 CNV in 2 samples within total 13 variants.Table: 210P

Signaling PathwaysGenetic AlterationsHR+/ HER2-(29)HER2  + (6)HR+/ HER2 + (6)TNBC(12)
p53TP53145411
PI3K/AKT/mTORPIK3CA12313
AKT16---
PTEN3---
NF11---
FLCN1---
Homologous recombination repairBRCA1(gm)---1
BRCA1(sc)-1--
BRCA2(gm)2---
BRCA2(sc)-1--
ATM(gm)--1-
Ras/Raf/MAPKHRAS1---
KRAS1--1
Cell cycleRB11---
CDKN2A1---
CCND11---
RTKsFGFR11-1-
HER2 CNV-45-
EGFR CNV---1

sc, somatic mutation; gm, germline mutation.

Conclusions

Genetic alterations were highly heterogeneous in different molecular subtypes of early-stage breast cancers. And this may contribute to the different relapse risk.

Clinical trial identification

Legal entity responsible for the study

Geneplus-Beijing.

Funding

Has not received any funding.

Editorial Acknowledgement

Disclosure

All authors have declared no conflicts of interest.

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings