Abstract 4263
Background
The complexity of breast cancer (BC) at the clinical, morphological and molecular level has been well demonstrated. Molecular profiling, which reveals the intrinsic biology among subtypes, has significantly advanced the management of this disease. However, previous studies have provided very limited molecular data on Chinese BC patients.
Methods
We performed capture-based targeted sequencing on plasma samples using a panel consisting of 102 BC related genes, spanning 249 kb of human genome, to interrogate the genomic landscape of 236 female Chinese BC patients and compared our results to the TCGA data set. Only genes covered by the panel and occurring in more than 10% patients from at least one subgroup were compared and contrasted between the two cohorts. The Chinese and the TCGA cohort had a median age of 48 and 58, respectively.
Results
Our cohort consisted of 55% triple negative breast cancer (TNBC), 10% luminal A, 27% luminal B and 8% HER2 positive BC. 53% of patients were post-menopausal. 190 patients had mutations found from this panel, resulting in a positive detection rate of 81%. Of the 46 patients with no mutation detected from this panel, 24 had TNBC. Collectively, we identified 921 mutations spanning 89 genes. First, we compared and contrasted mutation spectrum among the 4 subtypes. TP53mutations were more commonly seen in TNBC patients (p < 0.01), whereas FGF3, FGF4, FGF19and CCND1amplification were more likely to occur in patients with Lumina A or Luminal B BC (p = 0.002). Next, we compared the mutation spectrum of our cohort to TCGA dataset, and for luminal B breast cancer and TNBC, Chinese patients had significantly more PI3KCA mutation found. Furthermore, Chinese luminal A (p < 0.01) and luminal B (p < 0.01) patients had significantly higher TP53mutation frequency and Chinese HER2 positive BC patients (p < 0.01) had significantly lower TP53mutation frequency than TCGA dataset. In addition, we also identified 10 pathogenic or likely pathogenic BRCA1/2 mutations from this cohort, resulting in a prevalence rate of 4.2%.
Conclusions
We identified distinctive genomic patterns associated with Chinese breast cancer patients compared to TCGA data, suggesting the importance of mutation-based stratification according to ethnic status.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5658 - Detection of 5-hydroxymethylcytosine in Circulating-Free DNA for Early Diagnosis of Colorectal Cancer
Presenter: Tianyu Liu
Session: Poster Display session 2
Resources:
Abstract
5779 - Detection of 5-hydroxymethylcytosine in Circulating-Free DNA for Prediction of The Efficacy of Conversion Therapy for Colorectal Cancer Liver Metastases
Presenter: Wenju Chang
Session: Poster Display session 2
Resources:
Abstract
4672 - mCRC gene profiling using the Idylla platform
Presenter: Christopher Bricogne
Session: Poster Display session 2
Resources:
Abstract
3393 - PIK3CA mutation in metastatic colorectal cancer (mCRC): association with clinico-pathological features and outcome
Presenter: Valentina Fanotto
Session: Poster Display session 2
Resources:
Abstract
1317 - Patient-Derived Xenografts (PDX) Identifies JMJD6 Inhibitor as an Effective Therapeutic Medicine in Colorectal Cancer.
Presenter: Feng Ye
Session: Poster Display session 2
Resources:
Abstract
1228 - DACH1 induced stemness of intestinal organoids by directly suppressing BMP signaling and contributes to intestinal tumorigenesis
Presenter: Xiang Hu
Session: Poster Display session 2
Resources:
Abstract
1147 - miR-148a inhibits early relapsed colorectal cancers and the secretion of VEGF by indirectly targeting HIF-1α under non-hypoxia/hypoxia conditions
Presenter: Hsiang-lin Tsai
Session: Poster Display session 2
Resources:
Abstract
1158 - Long noncoding RNA CASC21 promotes cell proliferation and metastasis in colon cancer.
Presenter: Qun Zhang
Session: Poster Display session 2
Resources:
Abstract
1259 - Prognostic and Predictive Impact On FMS-like Tyrosine Kinase 3 (FLT3) Amplification In Patients With Metastatic Colorectal Cancer
Presenter: Hiroko Hasegawa
Session: Poster Display session 2
Resources:
Abstract
1452 - RBP-Jκ in colon cancer cells facilitates tumor associated macrophages (TAMs)-induced cell metastasis by secreting CXCL11
Presenter: Meng jie Liu
Session: Poster Display session 2
Resources:
Abstract