Abstract 59P
Background
BC is a heterogeneous disease with variable clinical outcomes among patients with the same clinical and pathological characteristics, treated with similar treatment. Despite significant improvement in the outcomes, many of them acquire resistance to multiple anticancer drugs, leading to recurrence and /or metastasis. It remains an unmet need to identify robust molecular defects and novel biomarkers to adopt individualized treatment decisions in BC. CGP using next generation sequencing (NGS) provides more druggable gene aberrations at “one go” that includes somatic BRCA (sBRCA), homologous recombinant repair pathway alteration (HRR) and tumor agnostic markers like tumor mutation burden (TMB) and microsatellite instability (MSI) burden.
Methods
140 BC cases at HCG cancer centre were profiled using Illumina TruSight Oncology 500 assay on a NextSeq2000 in an IRB-approved study. The findings from NGS data were discussed in the molecular tumor board (MTB) and recommendations were documented for change in clinical management and follow-up.
Results
Clinically relevant variants were detected in 133/140 BC patients (95%) with actionable mutations in >80% cases with direct impact on therapy and constituted of 47% Tier 1 and 41% Tier 2 mutations. CGP revealed a multitude of genomic alterations such as PI3KCA/AKT/PTEN signalling pathway (32%) in HR+Her2- mBC and ESR1 mutation (7%) in HR+ mBC predictive of resistance to anti-Her2 and endocrine therapy respectively. 22 patients (16%) with sBRCA and HRR pathways alteration treated either with platinum / PARP inhibitors post platinum treatment were found to have partial-to-complete pathological response (pCR). 23 BC patients with high TMB (16%) were initiated on immunotherapy as a single drug or in combination with chemotherapy and are on follow up. The mutation spectrum, HRR pathway alterations and high TMB of triple- negative BC (TNBC) cases revealed a distinctive mutational profile with clinical utility in >95% cases.
Conclusions
Recommending CGP tests at a more appropriate time helps in modifying BC treatment protocol, clinical decisions and provides patients with greater benefit from targeted treatments based on their specific gene alterations and resistance mechanism.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
B.S. Ajaikumar: Financial Interests, Personal and Institutional, Member of Board of Directors, Executive Chairman: HCG. All other authors have declared no conflicts of interest.
Resources from the same session
154P - Adverse events (AEs) as potential predictive factors of activity in patients with advanced hepatocellular carcinoma (HCC) treated with atezolizumab plus bevacizumab (AB)
Presenter: Mara Persano
Session: Poster Display
Resources:
Abstract
155P - Penpulimab combined with anlotinib and nab-paclitaxel plus gemcitabine (PAAG) as first-line treatment for advanced metastatic pancreatic cancer: A prospective, multicenter, single-arm, phase II study
Presenter: Juan Du
Session: Poster Display
Resources:
Abstract
156P - Phase II trial of second-line regorafenib in patients with unresectable hepatocellular carcinoma after progression on first-line atezolizumab plus bevacizumab: REGONEXT trial
Presenter: Jaekyung Cheon
Session: Poster Display
Resources:
Abstract
157P - T/N ratio and radiation dose delivered do not correlate with the development of Radioembolization-Induced Liver Disease (REILD) in Hepatocellular Carcinoma (HCC) following Y90 selective internal radiation therapy (Y90-SIRT): A retrospective, single tertiary centre cohort study
Presenter: Daniel Yang Yao Peh
Session: Poster Display
Resources:
Abstract
158P - Single-cell RNA sequencing via Endoscopic Ultrasoundguided Fine-Needle Biopsy (EUS-FNB) Pancreatic Biopsies uncovered an aggressive subclone with a poor prognosis
Presenter: Yung-yeh Su
Session: Poster Display
Resources:
Abstract
159P - Classical computer vision and modern deep-learning of pancreatic stroma histology features to diagnose cancer
Presenter: Abdelhakim Khellaf
Session: Poster Display
Resources:
Abstract
160P - Interim analysis of the NAPOLEON-2 study: Safety evaluation of nano-liposomal irinotecan with fluorouracil and folinic acid for advanced pancreatic cancer
Presenter: Wataru Kusano
Session: Poster Display
Resources:
Abstract
161P - Screening and COnsensus based on Practices and Evidence (SCOPE): Real-world survey on Japanese and rest-of-world practice patterns in resectable pancreatic cancer
Presenter: Elizabeth Smyth
Session: Poster Display
Resources:
Abstract
162P - Recurrence pattern of hepatocellular carcinoma patients receiving curative surgery of RFA: An update
Presenter: Long Chan
Session: Poster Display
Resources:
Abstract
163P - Chemotherapy versus palliative radiotherapy in advanced inoperable gall bladder cancer
Presenter: Vimal Sekar
Session: Poster Display
Resources:
Abstract