Impact of Neoadjuvant Chemoradiotherapy Versus Surgery Alone on Circulating Tumor Cells in Patients With Stage II-III Rectal Cancer and Negative Circumferential Resection Margin: a Multicenter Randomized Clinical Trial

What this Trial Is About

Researchers are investigating the effects of neoadjuvant chemoradiotherapy compared to primary surgery on circulating tumor cells (CTCs) in patients with stage II-III rectal cancer who do not have circumferential resection margin involvement. This prospective, multi-center, randomized clinical trial aims to clarify the role of CTCs as a biomarker for disease spread and treatment response. The study also evaluates perioperative outcomes, local recurrence, disease-free survival, and overall survival to help optimize treatment strategies for rectal cancer. Participants will be randomly assigned to one of two groups: one undergoing primary surgical resection with total mesorectal excision (TME), and the other receiving long-course neoadjuvant chemoradiotherapy followed by delayed surgery. The chemoradiotherapy includes conventional fractionation pelvic radiotherapy combined with standard fluoropyrimidine-based chemotherapy. Blood samples will be collected at set times before, during, and after treatment to monitor CTC presence and changes. Throughout the study, patients will undergo regular blood draws to assess CTC shape, size, and specific markers at multiple time points before and after treatment and surgery. Researchers will also track surgical complications within 30 days, long-term local recurrence, disease-free survival, and overall survival over 3 and 5 years. The total participation duration includes these assessments and follow-up evaluations to understand the prognostic significance of CTCs and treatment impacts.

Rectal Cancer CTC Trial