Advanced Liquid Biopsy Approach Detects Colorectal Cancer Recurrence Before Imaging

A novel, highly sensitive blood test utilizing circulating tumor DNA (ctDNA) has shown promise in detecting the recurrence of resectable colorectal cancer earlier than traditional imaging methods. Presented at the AACR Annual Meeting 2025, interim results from the VICTORI study reveal that this assay can identify signs of cancer returning up to a year before imaging confirms recurrence.

The study involved 71 patients with resectable colorectal cancer, ranging from stage 1 to stage 4. Researchers employed a personalized testing panel, derived from tumor tissue analysis, to monitor ctDNA levels before and after surgery over an extended period. All patients with more advanced disease had detectable ctDNA prior to surgery, and among the 65 patients assessed for outcomes, 23 experienced clinical recurrence.

Remarkably, in the majority of cases with recurrence, ctDNA was detected up to 198 days earlier than clinical or radiological evidence. One patient's recurrence was identified a staggering 416 days in advance. The levels of ctDNA varied significantly, with higher levels at initial detection associated with more rapid relapse.

This early detection capability could be transformative for clinical decision-making. It may help identify patients who need additional therapies early on, potentially improving survival rates. Conversely, patients with a good prognosis could be spared unnecessary chemotherapy, reducing treatment-related toxicities.

The study highlights that ctDNA detection as early as two weeks after surgery is feasible, although four weeks post-operation might be a more reliable window to optimize accuracy, considering normal cell-free DNA interference. While these promising results pave the way for future research, the study’s observational nature indicates that further randomized trials are necessary to determine how best to incorporate ctDNA testing into standard care.

Overall, this innovative approach underscores the potential of blood-based biomarkers to revolutionize post-surgical monitoring and personalized management in colorectal cancer patients.