Adjuvant Therapy Achieves ctDNA Clearance in 26% of Colorectal Cancer Patients, Improves Disease-Free Survival
核心洞察
The INTERCEPT CRC (搜索) study demonstrated that adjuvant therapy achieved circulating tumor DNA (搜索) (ctDNA (搜索)) clearance in 26% of colorectal cancer (搜索) patients who tested ctDNA-positive after surgery.
Patients with ctDNA (搜索) clearance on at least two tests showed significantly improved disease-free survival outcomes compared to those without clearance (P <.0001).
Spontaneous ctDNA (搜索) clearance without intervention occurred in only 4.2% of patients, with a median duration of 11.2 months, highlighting the importance of active treatment.
The INTERCEPT CRC (搜索) study has provided compelling evidence that adjuvant therapy can effectively clear circulating tumor DNA (搜索) (ctDNA (搜索)) in a significant portion of colorectal cancer (搜索) patients who remain ctDNA-positive after surgical resection. The findings, presented at the 2025 European Society for Medical Oncology (ESMO) Congress, demonstrate that ctDNA clearance correlates strongly with improved disease-free survival outcomes.
ctDNA Clearance Rates and Clinical Outcomes
Among 77 patients with ctDNA (搜索)-positive results after surgery, adjuvant therapy achieved ctDNA clearance in 26% (n = 20), with 17% (n = 13) showing clearance on at least two tests. This clearance translated into significantly improved disease-free survival outcomes from the time of first ctDNA-positive test result in both stage I-III CRC (搜索) patients (P <.0001) and stage IV disease patients (P <.0001).
"Adjuvant treatment can clear a quarter of the patients [who] are ctDNA (搜索) positive postoperatively. Those with ctDNA clearance had superior DFS," stated presenting author Emerik Osterlund, MD, PhD, a postdoctoral fellow in Gastrointestinal Medical Oncology at The University of Texas MD Anderson Cancer Center.
ctDNA Dynamics Following Treatment
The study revealed distinct patterns in ctDNA (搜索) dynamics after surgical intervention. Initial post-surgical or ablation data showed that 69% of patients had ctDNA negativity on all tests, while 18% had positive results on all tests. Additionally, 3.1% had ctDNA clearance on at least two tests, 2.4% had clearance on one test, and 8% converted from ctDNA negativity to positivity.
Following adjuvant therapy, the distribution shifted favorably, with 70% of patients achieving ctDNA (搜索) negativity on all tests and 19% maintaining positive results on all tests. The conversion rates also changed, with 1.5% showing ctDNA negativity on at least two tests, 1.4% having clearance on one test, and 9% converting from ctDNA negativity to positivity.
Limited Spontaneous Clearance
The study highlighted the rarity of spontaneous ctDNA (搜索) clearance without therapeutic intervention. Among 403 patients who had ctDNA-positive results at any time after surgery and adjuvant treatment, only 4.2% showed at least one subsequent negative reading without intervention. Even fewer patients (2.1%) had ctDNA-negative results on at least two sequential tests without intervention, and 1.7% had no recurrences at follow-up.
Among patients with spontaneous ctDNA (搜索) clearance, the median duration of clearance was 11.2 months, and the mean tumor molecules per milliliter was 0.06 (range, 0.02-1.89). "The rate and durability of [spontaneous] ctDNA clearance was very low," Osterlund noted.
Study Design and Population
The INTERCEPT program enrolled 1,301 patients with newly diagnosed or previously treated resectable stage I to IV colorectal cancer (搜索), with 53% having stage I-III disease and 47% having stage IV disease. Patients received standard-of-care therapy including surgical resection with or without neoadjuvant and adjuvant treatment, and underwent tissue collection and ctDNA (搜索) testing in the postoperative setting.
Investigators conducted routine surveillance via imaging and laboratory tests, with ctDNA (搜索) assay testing occurring approximately every three months at each surveillance visit. This comprehensive monitoring approach allowed for detailed tracking of ctDNA dynamics throughout the treatment and follow-up periods.
Clinical Implications
The findings support the use of ctDNA (搜索) as a predictive biomarker for adjuvant treatment benefit in colorectal cancer (搜索). According to Osterlund, previous studies have demonstrated ctDNA's utility in monitoring minimal residual disease, with ctDNA positivity representing a strong risk factor for disease recurrence following curative-intent procedures.
"ctDNA (搜索) clearance is useful for seeing potential benefit in novel therapeutic studies," Osterlund concluded, suggesting broader applications for this biomarker in future clinical research and treatment optimization strategies.