An interventional study of Primary Surgery and Neoadjuvant radiochemotherapy and surgery in Rectal Cancer Patients, sponsored by University Hospital Ostrava. Recruiting at 4 sites in Czechia. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-09-26.
Sponsored by University Hospital Ostrava · Not applicable, Interventional, and Treatment
This prospective, multi-centre, randomised clinical trial aims to compare the effect of neoadjuvant chemoradiotherapy versus primary surgery on circulating tumor cells (CTCs) in patients with stage II-III rectal cancer without circumferential resection mar-gin involvement. CTCs are considered a promising biomarker for disease dissemination and treatment response. Patients will be randomized to either primary surgical resection with total mesorectal excision or long-course neoadjuvant chemoradiotherapy followed by surgery. Serial blood samples will be collected at predefined time points to assess the presence and dynamics of CTCs. Secondary endpoints include perioperative morbidity and mortality, local recurrence rate, disease-free survival, and overall survival. The results of this study may provide new insights into the prognostic role of CTCs and contribute to optimising treatment strategies for rectal cancer.
Colorectal cancer remains one of the most common malignancies worldwide, and rectal cancer requires a multidisciplinary treatment approach. For patients with locally advanced rectal cancer, neoadjuvant chemoradiotherapy (nCRT) followed by surgical resection has been widely used to reduce the risk of local recurrence. However, the indication for nCRT in patients without circumferential resection margin (CRM) involvement remains controversial. While some studies have suggested benefits of nCRT, others have shown comparable oncological outcomes with primary surgery when high-quality total mesorectal excision (TME) is performed.
Circulating tumor cells (CTCs) are malignant cells detectable in peripheral blood that have been associated with metastatic potential and poor prognosis in various cancers, including colorectal cancer. Monitoring the presence and dynamics of CTCs offers a minimally invasive "liquid biopsy" approach that may provide prognostic information and reflect treatment efficacy. Existing evidence suggests that changes in CTC levels after surgery or systemic therapy may correlate with recurrence risk and survival, but relevant data in rectal cancer patients undergoing multimodal treatment are limited.
This prospective, multi-centre, randomised clinical trial will enrol patients with stage II-III rectal cancer without evidence of CRM involvement on staging magnetic resonance imaging (MRI). Eligible patients will be randomized into two study arms:
Peripheral blood samples will be collected at predefined time points in both groups to determine the presence and quantity of CTCs. The primary objective is to compare the effect of neoadjuvant chemoradiotherapy versus surgery alone on CTC dynamics.
Secondary objectives include:
By integrating CTC monitoring into a modern randomized clinical trial design, this study aims to clarify the prognostic value of CTCs in rectal cancer and determine whether specific treatment strategies are associated with more favourable biological and clinical outcomes. The findings may contribute to more individualised treatment planning and potentially reduce the risk of recurrence and mortality in rectal cancer patients.
227 studies on the registry are indexed under Neoplastic Cells, Circulating; 54 are open to participants now.
This study's planned enrollment of 120 is above the median of 83 across 100 interventional studies indexed under Neoplastic Cells, Circulating.
Browse Neoplastic Cells, Circulating studies →University Hospital Ostrava is the lead sponsor of 148 studies on the registry; 50 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Procedure: rectal resection with TME (Total Mesorectal Excision)
Procedure: Primary Surgery
Procedure: rectal resection with TME performed 6-10 weeks after completion of chemoradiotherapy.
Procedure: Neoadjuvant radiochemotherapy and surgery
Patients undergo radical surgical resection with TME without preceding neoadjuvant therapy
Neoadjuvant treatment: long-course pelvic radiotherapy (conventional fractionation) with concurrent chemotherapy (standard fluoropyrimidine-based regimen)
Circulating Tumor Cells (CTC) Dynamics - neoadjuvant treatment - shape
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The presence of CTC round shape will be observed.
Time frame: (1) before the initiation of CRT, (2) 1 week and (3) 1 month after the initiation of CRT, (4) preoperatively (1-2 weeks before surgery), (5) 1 week postoperatively, and (6) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - neoadjuvant treatment - size
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The CTC size will be observed, with the border value of \> 4 μm.
Time frame: (1) before the initiation of CRT, (2) 1 week and (3) 1 month after the initiation of CRT, (4) preoperatively (1-2 weeks before surgery), (5) 1 week postoperatively, and (6) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - neoadjuvant treatment - DAPI positivity
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The DAPI positivity will be observed. A DAPI-positive nucleus is a cell nucleus that has been stained with DAPI (4',6-diamidino-2-phenylindole), a fluorescent dye that binds specifically to the adenine-thymine (A-T) rich regions of double-stranded DNA.
Time frame: (1) before the initiation of CRT, (2) 1 week and (3) 1 month after the initiation of CRT, (4) preoperatively (1-2 weeks before surgery), (5) 1 week postoperatively, and (6) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - neoadjuvant treatment - pancytokeratin and/or EpCAM positivity
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The presence of pancytokeratin and/or EpCAM positivity in CTCs will be observed. EpCAM positivity refers to the presence of EpCAM (Epithelial Cell Adhesion Molecule) protein on cells, which is a marker primarily expressed on epithelial cells and in many carcinomas.
Time frame: (1) before the initiation of CRT, (2) 1 week and (3) 1 month after the initiation of CRT, (4) preoperatively (1-2 weeks before surgery), (5) 1 week postoperatively, and (6) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - neoadjuvant treatment - CD45 negativity
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The presence of CD45 negativity in CTCs will be observed. "CD45 negative" means a cell does not express the CD45 protein on its surface.
Time frame: (1) before the initiation of CRT, (2) 1 week and (3) 1 month after the initiation of CRT, (4) preoperatively (1-2 weeks before surgery), (5) 1 week postoperatively, and (6) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - primary surgery - shape
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The presence of CTC round shape will be observed.
Time frame: (1) preoperatively (1-2 weeks before surgery), (2) 1 week postoperatively, and (3) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - primary surgery - size
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The CTC size will be observed, with the border value of \> 4 μm.
Time frame: (1) preoperatively (1-2 weeks before surgery), (2) 1 week postoperatively, and (3) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - primary surgery - DAPI positivity
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The DAPI positivity will be observed. A DAPI-positive nucleus is a cell nucleus that has been stained with DAPI (4',6-diamidino-2-phenylindole), a fluorescent dye that binds specifically to the adenine-thymine (A-T) rich regions of double-stranded DNA.
Time frame: (1) preoperatively (1-2 weeks before surgery), (2) 1 week postoperatively, and (3) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - primary surgery - pancytokeratin and/or EpCAM positivity
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The presence of pancytokeratin and/or EpCAM positivity in CTCs will be observed. EpCAM positivity refers to the presence of EpCAM (Epithelial Cell Adhesion Molecule) protein on cells, which is a marker primarily expressed on epithelial cells and in many carcinomas.
Time frame: (1) preoperatively (1-2 weeks before surgery), (2) 1 week postoperatively, and (3) 1 month postoperatively
Circulating Tumor Cells (CTC) Dynamics - primary surgery - CD45 negativity
The detection of CTC in laboratory will be performed using fluorescence microscope. Potential CTC candidates (hotspots) were identified based on green fluorescence and subjected to operator review. The presence of CD45 negativity in CTCs will be observed. "CD45 negative" means a cell does not express the CD45 protein on its surface.
Time frame: (1) preoperatively (1-2 weeks before surgery), (2) 1 week postoperatively, and (3) 1 month postoperatively
Short-term postoperative outcomes - preoperative complications
The occurrence of perioperative complications will be observed
Time frame: Within 30 days after surgery
Short-term postoperative outcomes - 30-day morbidity
30-day morbidity will be observed
Time frame: Within 30 days after surgery
Short-term postoperative outcomes - 30-day mortality
30-day mortality will be observed
Time frame: Within 30 days after surgery
Local recurrence rate
Cumulative incidence of local tumor recurrence after treatment.
Time frame: Up to 5 years
Disease-free survival (DFS)
Interval from treatment to recurrence, progression, or death.
Time frame: 3 and 5 years after surgery
Overall survival (OS)
Proportion of patients alive at 3 and 5 years.
Time frame: 3 and 5 years after surgery
Plan to share: No — There is no plan to make individual participant data available to other researchers. The data may be provided upon reasonable request.
Started Apr 2025 (actual). Primary completion is estimated for Mar 2028, 35 months after the start.
Of 40 non-industry interventional studies with no phase under Neoplastic Cells, Circulating, half reached primary completion within 41 months of starting (the median), counting those still running; a quarter within 23 and three quarters within 84. This study's planned 35 months is below that.
Counting every sponsor, half of 42 studies reached it within 41 months; a quarter within 23 and three quarters within 84.
How these figures are worked out, and which studies are left out of them.
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