Abstract 417P
Background
An increasing amount of research suggests that the presence of minimal residual dis-ease (MRD) after curative-intent surgery for early-stage cancers is associated with disease recurrence. Circulating tumor DNA (ctDNA) has emerged as a promising biomarker for MRD assessment in patients with colorectal cancer (CRC) who have undergone surgery or completed adjuvant therapy. MRD tests are already available for use in clinics; however, treatment decisions following MRD results obtained in routine practice are infrequently described.
Methods
In this study, we report on the real-world clinical use of Guardant Reveal, a validated tissue-agnostic MRD assay which assesses genomic mutations as well as methylation sigantures, in the first 82 consecutive patients (102 samples) with CRC tested in Asia and the Middle East.
Results
Overall, 24% of patients had ctDNA detected in their first MRD test, and the frequency of ctDNA positivity increased with increasing tumor stage. Among all ctDNA-positive samples, 48% had evidence of MRD only through the detection of methylation signals, while 26% had both genomic alterations and methylation signals. In patients with stage II CRC, 78% of tests were ordered within 12 weeks after resection, while for patients with stage III disease, 63% of tests were ordered during surveillance. We also describe real-life clinical cases utilizing tissue-agnostic MRD assessment. Most of the physicians included MRD test results in the treatment pla.
Conclusions
Through retrospective analysis of real-world data, we describe how physicians in Asia and the Middle East currently apply a commercially available tissue-agnostic MRD assay in clinical decision-making for patients after surgical resection of colorectal cancer. The addition of methylation assessment to somatic mutation detection contributed to the detection of MRD in samples without mutation. Results from prospective randomized studies will further define the clinical role of MRD detection in resectable CRC. Evidence for tissue-agnostic MRD assays is building across tumor types with continuous improvements in sensitivity and specificity.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
S.S. Jain, S. Hsing, N. Joshi: Financial Interests, Personal, Full or part-time Employment: Guardant Health. All other authors have declared no conflicts of interest.
Resources from the same session
270P - Germline BRCA1/2 pathogenic variants in Japanese patients with prostate cancer are predictive factors for androgen receptor-axis-targeted therapy or chemotherapy for castration-resistant prostate cancer
Presenter: Shigekatsu Maekawa
Session: Poster Display
Resources:
Abstract
271P - Prostate cancer with histone modifier UTX mutations can benefit from olaparib
Presenter: NOBUHITO MURAMOTO
Session: Poster Display
Resources:
Abstract
272P - Comparison between MRI-targeted and standard biopsy for prostate cancer detection: A systematic review and meta-analysis
Presenter: Andree Kurniawan
Session: Poster Display
Resources:
Abstract
273P - The diagnostic performance of cognitive MRI-targeted biopsy in biopsy-naïve patients undergoing systematic 14-region 18-core biopsy: Do the three areas affect the results?
Presenter: Yuka Toyama
Session: Poster Display
Resources:
Abstract
274P - Index tumor location influencing early biochemical recurrence after radical prostatectomy in patients with negative surgical margins
Presenter: Jun Akatsuka
Session: Poster Display
Resources:
Abstract
275P - Prognosis of metastatic castration-resistant prostate cancer in response to chemotherapy and PSMA expression in circulating tumor cells
Presenter: Naoya Nagaya
Session: Poster Display
Resources:
Abstract
276P - Prognostic significance of p53 mutation in metastatic hormone-sensitive prostate cancer
Presenter: Lakshmi Kamala
Session: Poster Display
Resources:
Abstract
277P - Vasohibin-1 expression as a biomarker of aggressive growth in prostate ductal adenocarcinoma
Presenter: Murad Salomov
Session: Poster Display
Resources:
Abstract
278P - Full-coverage radiotherapy for prostate cancer patients with oligometastases
Presenter: Bichun Xu
Session: Poster Display
Resources:
Abstract
279P - Hypofractionated radiotherapy protocol implementation and early outcomes for prostate cancer patients: A single institution retrospective review
Presenter: Thu Nguyen
Session: Poster Display
Resources:
Abstract