Rectal Cancer, AdenocarcinomaNOM-HDR-WNCT07786493
HDR Endorectal Brachytherapy With 3D-Printed Guidance and Local Shielding for Rectal Cancer Organ Preservation
A study testing High-Dose-Rate Endorectal Brachytherapy in people with Rectal Cancer, Adenocarcinoma, run by Tianjin Medical University Cancer Institute and Hospital at 1 site in China.
Trial summary
This prospective, single-center, single-arm phase II study will evaluate the efficacy, safety, and technical feasibility of an organ-preserving radiotherapy strategy for patients with localized rectal adenocarcinoma who are medically inoperable, decline radical surgery, or are considered technically unresectable… Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Rectal Cancer, Adenocarcinoma
- What is being tested?
- High-Dose-Rate Endorectal Brachytherapy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 50 participants
- Where
- 1 siteChina
- Study dates
- 1 Sep 2026to 30 Nov 2030
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18-80 years.
- Histologically confirmed rectal adenocarcinoma.
- Clinical stage cT2-4, any N, M0.
- Patients who are elderly or frail, medically unsuitable for radical surgery, refuse radical surgery, or are considered by a multidisciplinary team (MDT) to have disease for which safe R0 resection is technically difficult.
- Considered by the MDT and investigators to be suitable for a definitive non-operative treatment strategy.
- ECOG performance status 0-2; patients with ECOG performance status 3 may be eligible if considered by the MDT to be able to tolerate the study treatment.
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- Estimated life expectancy of at least 6 months.
- Considered suitable for pelvic external beam radiotherapy and HDR endorectal brachytherapy.
- Tumor location, endorectal access, and local anatomy suitable for HDR brachytherapy using the individualized 3D-printed guide template.
- Adequate hematologic, hepatic, and renal function for the planned treatment.
- Ability to understand the study requirements and provide written informed consent.
Who cannot join
- Distant metastatic disease or disease considered unsuitable for definitive local non-operative treatment.
- Prior definitive pelvic radiotherapy.
- Intestinal perforation, complete bowel obstruction, uncontrolled active bleeding, or severe active infection.
- Anatomical or clinical conditions precluding HDR endorectal brachytherapy or use of the individualized guide template/local shielding platform.
- Inflammatory bowel disease.
- Severe uncontrolled cardiopulmonary disease, significant bone marrow suppression, or severe hepatic or renal dysfunction.
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- Pregnancy or breastfeeding.
- Concurrent participation in another clinical trial that may interfere with evaluation of the study treatment or endpoints.
- Any other condition considered by the investigator to make the patient unsuitable for participation in the study.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
Tianjin Medical University Cancer Institute and Hospital
Tianjin, Tianjin Municipality, 300060
Yuanjie Cao, MD, 86-18522123151, cyjro325@tjmuch.com
Yuanjie Cao, MD
About this study
Official title: A Prospective Single-Arm Phase II Study of Pelvic External Beam Radiotherapy Followed by HDR Endorectal Brachytherapy Combined With a 3D-Printed Individualized Guide Template and Tungsten-Alloy Local Shielding for Organ Preservation in Inoperable Localized Rectal Cancer
This prospective, single-center, single-arm phase II study will evaluate the efficacy, safety, and technical feasibility of an organ-preserving radiotherapy strategy for patients with localized rectal adenocarcinoma who are medically inoperable, decline radical surgery, or are considered technically unresectable without distant metastases.
Participants will receive pelvic external beam radiotherapy followed by high-dose-rate (HDR) endorectal brachytherapy. Concurrent capecitabine may be given during external beam radiotherapy to participants who are considered able to tolerate chemotherapy. During HDR brachytherapy, all participants will be treated using a patient-specific 3D-printed guide template and individualized tungsten-alloy local shielding. The guide template is designed to improve applicator positioning and treatment reproducibility, while the local shielding is intended to reduce radiation exposure to non-target rectal wall.
The study will enroll 50 participants. The primary objectives are to evaluate the 12-month clinical complete response rate and the technical completion rate of the HDR brachytherapy platform. Secondary assessments include organ preservation, local regrowth, survival outcomes, treatment-related toxicity, quality of life, and anorectal function.
Read the detailed description
This investigator-initiated study is a prospective, open-label, single-arm phase II trial evaluating a definitive non-operative treatment strategy for localized rectal cancer. Eligible participants will have histologically confirmed rectal adenocarcinoma without distant metastases and will be considered medically unsuitable for radical surgery, decline radical surgery after appropriate counseling, or be considered technically unresectable by multidisciplinary assessment.
Following baseline evaluation and multidisciplinary review, participants will receive pelvic external beam radiotherapy. The planned dose to the pelvic planning target volume is 45 Gy in 25 fractions. Radiologically positive or highly suspicious lymph nodes will receive a simultaneous integrated boost to 55 Gy in 25 fractions, with escalation to 58-58.25 Gy in 25 fractions permitted when considered dosimetrically safe. Concurrent capecitabine at 825 mg/m² twice daily on radiotherapy days may be administered to participants who are considered able to tolerate chemotherapy; concurrent chemotherapy is not mandatory in this study.
Participants will undergo reassessment approximately 4-6 weeks after completion of external beam radiotherapy before proceeding to HDR endorectal brachytherapy. The planned HDR boost is 6 Gy per fraction for 3 fractions using an iridium-192 source, with fractions generally separated by 5-7 days.
During all HDR fractions, a patient-specific 3D-printed guide template will be used for applicator positioning, fixation, and reproducibility. Individualized flexible tungsten-alloy shielding, typically approximately 3 mm thick, will be positioned within a predefined channel in the template before treatment. The shielding configuration will be individualized according to tumor distribution and the location of non-target rectal wall requiring protection. Because the shielding material may produce substantial computed tomography artifacts, treatment planning will be performed before placement of the tungsten-alloy shielding, followed by verification of shielding direction, depth, and fixation before irradiation.
Tumor response will be assessed using a combination of digital rectal examination, endoscopy, and pelvic magnetic resonance imaging. Participants achieving a clinical complete response will enter a structured watch-and-wait follow-up program. Participants with residual disease, local regrowth, or progression will undergo multidisciplinary reassessment for individualized salvage treatment when appropriate.
In addition to clinical response and organ-preservation outcomes, the study will prospectively evaluate treatment-related toxicity and the technical performance of the individualized brachytherapy platform, including treatment completion, geometric reproducibility, shielding implementation, and dosimetric parameters.
- Conditions
- Rectal Cancer, Adenocarcinoma
- Being tested
- High-Dose-Rate Endorectal Brachytherapy
- Keywords
- Rectal cancer, Organ preservation, High-dose-rate brachytherapy, Endorectal brachytherapy, 3D-printed template, Tungsten alloy shielding
- Medical subject headings
- Rectal Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
High-Dose-Rate Endorectal BrachytherapyRadiation
High-dose-rate (HDR) endorectal brachytherapy will be delivered as a local dose-intensification component of the organ-preserving treatment strategy for rectal cancer. Brachytherapy will be performed using image-guided, patient-specific treatment planning to optimize target coverage while limiting radiation exposure to adjacent organs at risk. Treatment technique, applicator placement, dose prescription, and fractionation will be performed according to the study protocol.
| Study group | Role | What they receive |
|---|---|---|
| HDR Brachytherapy-Based Organ Preservation | Experimental | Participants will receive definitive organ-preserving treatment for rectal cancer, including external beam radiotherapy with concurrent chemotherapy as clinically indicated, followed by high-dose-rate brachytherapy for local dose intensification. Patient-specific treatment planning and study-specific brachytherapy techniques will be performed according to the study protocol. Receives: Radiation: High-Dose-Rate Endorectal Brachytherapy |
What is being measured
The primary outcome is the main question the study is designed to answer.
12-Month Clinical Complete Response Rate
Percentage of participants who maintain a clinical complete response (cCR) at 12 months after completion of study treatment, without local regrowth and without rectal cancer-related salvage resection. Clinical response will be assessed using a composite evaluation including digital rectal examination, endoscopy, and pelvic magnetic resonance imaging.
Measured: From completion of study treatment through 12 months
Technical Completion Rate of HDR Brachytherapy
Percentage of participants who complete all three planned high-dose-rate (HDR) endorectal brachytherapy fractions using the study-specific 3D-printed individualized guide template and tungsten alloy local shielding platform as required by the study protocol.
Measured: Through completion of HDR brachytherapy, approximately 8-10 weeks after completion of external beam radiotherapy
Secondary outcomes (10)
Overall Clinical Complete Response Rate
Percentage of participants who achieve a clinical complete response (cCR) after completion of study treatment. Clinical response will be assessed using a composite evaluation including digital rectal examination, endoscopy, and pelvic magnetic resonance imaging.
Measured: From completion of study treatment through 12 months
Near-Clinical Complete Response Rate
Percentage of participants classified as having a near-clinical complete response (near-cCR) after completion of study treatment based on composite assessment using digital rectal examination, endoscopy, and pelvic magnetic resonance imaging.
Measured: From completion of study treatment through 12 months
12-Month Organ Preservation Rate
Percentage of participants who remain alive with the rectum in situ and without rectal cancer-related radical salvage resection at 12 months after completion of study treatment.
Measured: From completion of study treatment through 12 months
Local Regrowth Rate
Percentage of participants who develop local tumor regrowth after achieving a clinical complete response or near-clinical complete response during follow-up. Local regrowth will be assessed using digital rectal examination, endoscopy, pelvic magnetic resonance imaging, and other clinically indicated assessments.
Measured: From completion of study treatment through 24 months
Local Failure-Free Survival
Time from completion of study treatment to the first occurrence of local treatment failure or death, whichever occurs first.
Measured: from enrollment through 24 months
Progression-Free Survival
Time from completion of study treatment to the first documented disease progression, local or distant recurrence, or death from any cause, whichever occurs first.
Measured: from enrollment through 24 months
Overall Survival
Time from completion of study treatment to death from any cause.
Measured: from enrollment through 24 months
Stoma-Free Survival
Time from completion of study treatment to permanent stoma creation or death from any cause, whichever occurs first.
Measured: from enrollment through 24 months
Incidence of Acute Treatment-Related Adverse Events
Percentage of participants experiencing acute treatment-related adverse events, with particular attention to grade 3 or higher gastrointestinal toxicity, bleeding, pain, ulceration, stenosis, and treatment-related functional impairment. Adverse events will be graded according to NCI-CTCAE version 5.0.
Measured: From initiation of study treatment through 90 days after completion of study treatment
Incidence of Late Treatment-Related Adverse Events
Percentage of participants experiencing late treatment-related adverse events, with particular attention to grade 3 or higher gastrointestinal toxicity, rectal bleeding, ulceration, stenosis, pain, and treatment-related functional impairment. Adverse events will be graded according to NCI-CTCAE version 5.0.
Measured: From more than 90 days after completion of study treatment through 24 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted26 Aug 2026
- Study start1 Sep 2026
- Primary completion30 Nov 2029 (estimated)
- Study completion30 Nov 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Rectal Cancer, AdenocarcinomaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 50 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Tianjin Medical University Cancer Institute and Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Yuanjie Cao, MD, Principal investigator, Tianjin Medical University Cancer Institute and Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07786493
- Sponsor's protocol ID
- E20260970
- Acronym
- NOM-HDR-W
- Status last verified
- Aug 2026
- First submitted
- 20 Aug 2026
- Last updated
- 11 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data (IPD) will not be publicly shared due to participant privacy and data protection considerations. Aggregate study results will be reported through scientific publications and/or presentations.
Publications
Cao Y, Li C, Zhang B, Chen J. HDR Endorectal/Endoluminal Brachytherapy Boost in Rectal Organ Preservation: A Systematic Review and Meta-Analysis. Cancers (Basel). 2026 May 6;18(9):1494. doi: 10.3390/cancers18091494.
PubMed 42122288