Abstract 3182
Background
Clonal hematopoiesis (CH) leads to blood-derived somatic mutations in KRAS, NRAS and BRAF. Our aim is to identify the prevalence of CH-derived mutations in these three genes in metastatic colorectal cancer (mCRC) patients and reveal the practical clinical implication of these mutations on plasma cell-free DNA (cfDNA) genotyping.
Methods
We analyzed KRAS, NRAS and BRAF genotypes in plasma and matched tumor tissues of 236 mCRC patients through next-generation sequencing (NGS). Suspected CH mutations were defined as those only present in plasma with variant allelic frequencies (AFs) <5% and were confirmed by paired peripheral blood cells (PBCs) using droplet digital PCR (ddPCR). The hemopoietic lineage harboring a CH-derived mutation was analyzed through flow cytometry.
Results
We identified suspected CH mutations in twenty patients (8.4%, 20/236). Three of these patients (1.27%, 3/236) had a CH-derived KRAS mutation. Two of them had a KRAS G12X and the third had a KRAS Q61H. We did not detect CH-derived NRAS or BRAF mutations. Patients harboring a CH-derived mutation previously received chemotherapy treatment. In one CH-derived KRAS G12X case, the mutation was enriched in lymphocytes and persisted in cfDNA over the course of 4 months of therapy.
Conclusions
We confirmed the existence of CH-derived KRAS mutations in a small proportion of mCRC patients. This should be noted to prevent misclassification as tumor somatic mutations when performing cfDNA sequencing.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
The National Natural Science Foundation of China (81572064, 81772263, 81772511, 81602038), the Key Developing Disciplines of Shanghai Municipal Commission of Health and Family Planning (2015ZB0201), the Projects from the Shanghai Science and Technology Commission (16411952100), the Projects from Zhongshan Hospital, Fudan University (2018ZSLC05).
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5124 - STAR_PAC: Phase I clinical trial repurposing all trans retinoic acid (ATRA) as stromal targeting agent in a novel drug combination for pancreatic cancer.
Presenter: Hemant Kocher
Session: Poster Display session 2
Resources:
Abstract
5257 - Outcomes of First Line FOLFIRINOX (FFX) Versus Gemcitabine and Nab-Paclitaxel (GN) in Patients with Advanced Pancreatic Cancer: Multi-Institutional Canadian Sites Experience
Presenter: Neha Papneja
Session: Poster Display session 2
Resources:
Abstract
1166 - Effect of prior cancer on survival outcomes for patients with pancreatic adenocarcinoma
Presenter: Chaobin He
Session: Poster Display session 2
Resources:
Abstract
1169 - Association of combination of irreversible electroporation ablation and chemotherapy with outcomes of locally advanced pancreatic cancer: a large cohort study
Presenter: Chaobin He
Session: Poster Display session 2
Resources:
Abstract
1222 - Results from phase I study of the oncolytic viral immunotherapy agent Canerpaturev (C-REV) in combination with gemcitabine plus nab-paclitaxel as first-line treatment of unresectable pancreatic cancer
Presenter: Yusuke Hashimoto
Session: Poster Display session 2
Resources:
Abstract
1698 - Multicenter retrospective study of gemcitabine plus nab-paclitaxel for elderly patients with advanced pancreatic cancer
Presenter: Masato Ozaka
Session: Poster Display session 2
Resources:
Abstract
2424 - Irinotecan Combined with Oxaliplatin and S1 in Patients with Metastatic Pancreatic Adenocarcinoma
Presenter: Keke Nie
Session: Poster Display session 2
Resources:
Abstract
2885 - Cancer-associated thrombosis in patients with pancreatic cancer and its correlation with plasma tissue factor level: A Japanese prospective cohort study
Presenter: Satoshi Kobayashi
Session: Poster Display session 2
Resources:
Abstract
3702 - A Phase I/Ib, multi-center trial of ARQ-761 (Beta-Lapachone) with gemcitabine/nab-Paclitaxel in patients with advanced pancreatic cancer
Presenter: Muhammad Beg
Session: Poster Display session 2
Resources:
Abstract
5185 - Systemic administration of the hyaluronidase-expressing oncolytic adenovirus VCN-01 in patients with advanced or metastatic pancreatic cancer: first-in-human clinical trial
Presenter: Rocio Garcia-Carbonero
Session: Poster Display session 2
Resources:
Abstract