The American Society of Clinical Oncology's (ASCO) 2026 Gastrointestinal Cancers Symposium just wrapped up. From January 8 through January 10, the three-day event in San Francisco, California, drew thousands of attendees and hundreds of exhibitors, making it an excellent opportunity to learn about the latest in gastrointestinal cancer research and network with peers.
Below, we have a curated selection of abstracts presented during the 2026 ASCO Gastrointestinal Cancers Symposium. The associated descriptions and conclusions were edited for clarity and brevity, where appropriate. View the full-text versions of each abstract through the links provided. For a full look at all the abstracts presented during the 2026 ASCO Gastrointestinal Cancers Symposium, view the abstracts and presentations archive.
2026 Gastrointestinal Cancers Symposium Abstracts on Colorectal Cancer
Characterization of piwi-RNA Signatures in Colorectal Cancer
- Description: This study evaluated PIWI-interacting RNAs (piRNAs) as potential biomarkers for colorectal cancer.
- Conclusion: Differentially expressed piRNAs show strong diagnostic and prognostic utility in CRC. The piRNA-based prognostic model outperformed existing signatures, suggesting that piRNAs may represent more reliable biomarkers. In particular, piR-36011 emerges as a promising dual-purpose biomarker linked to colorectal cancer oncogenesis.
Role of Cell-Intrinsic C5AR1 in Colorectal Cancer Survival and Chemoresistance
- Description: [The researchers] hypothesized that colorectal cancer tumors locally generate C5a, with cancer cell-intrinsic C5AR1 driving survival and chemoresistance.
- Conclusion: Pharmacologic C5AR1 inhibition synergizes with chemotherapy, positioning the C5a-C5AR1 axis as a tractable therapeutic vulnerability.
Aspirin Use and PI3K Mutations in Metastatic Colorectal Cancer
- Description: [The researchers] evaluated overall survival in metastatic colorectal cancer patients by PI3K status and aspirin use.
- Conclusion: PIK3CA and PI3K pathway mutations are associated with worse prognosis in mCRC, particularly among patients not receiving aspirin. This effect was not observed in aspirin users with no significant interaction detected.
Predictive and Prognostic Role of Protease-Activated Receptors in Colorectal Cancer
- Description: Protease-activated receptors (PARs) are G-protein-coupled receptors activated by thrombin and tissue factor (TF)-VIIa complexes. In colorectal cancer, TF promotes thrombosis, tumor progression, and therapy resistance in part through PAR signaling. We evaluated expressions of F2R (PAR-1), F2RL1 (PAR-2), F2RL2 (PAR-3), and F2RL3 (PAR-4) and their associations with prognosis and treatment outcomes in colorectal cancer.
- Conclusion: High PAR-3 expression was associated with significantly prolonged overall survival and may serve as an independent prognostic biomarker in colorectal cancer. Associations with improved outcomes with bevacizumab suggest a potential link between PAR-3 signaling and angiogenic pathways. In contrast, high PAR-1 expression correlated with inferior progression-free survival and significantly worse outcomes with cetuximab, potentially reflecting interaction with mechanisms of epidermal growth factor receptor resistance.
Real-World Outcomes for Pembrolizumab in MSI-High (MSI-H) Advanced Colorectal Cancer
- Description: [The researchers] evaluated the efficacy and safety of pembrolizumab in this patient population [patients with MSI-H/mismatch repair deficient (MMRd) advanced stage colorectal cancer] in a UK Cancer Network.
- Conclusion: Pembrolizumab showed a favorable response in about 50% of patients, more than comparable with the 43.8% response rate observed in KEYNOTE-177. However, grade 3 or higher adverse events were more frequent (34% vs. 22%) but were overall manageable for nearly half of patients.
- Description: [The researchers] examined reasons for readmission, comorbidity prevalence, healthcare utilization, and socioeconomic factors in right- versus left-sided colorectal cancer.
- Conclusion: Ninety-day readmission rates were similar between right- and left-sided colorectal cancer, though slightly higher in right-sided disease.
Sign up for alerts and stay informed on the latest published guidelines and articles.
Copyright © 2026 Guideline Central, all rights reserved.