Higher versus standard radiotherapy dose with chemotherapy for early rectal cancer
Compares two radiotherapy doses with capecitabine in adults with early rectal cancer.
Plain-language title generated from the registry record
Registry title: Standard Dose Versus High Dose of Radiotherapy in Rectal Preservation With Chemo-radiotherapy in Rectal Cancer Patients
Key facts
- Where
- Aalborg, Copenhagen, Næstved, Roskilde, and Vejle, DenmarkSee the 5 sites
- Phase
- Phase 3
AI summary: who the study is looking for
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults with early low or mid rectal cancer who are planned for chemoradiotherapy to try to avoid surgery. It compares a standard and a higher radiotherapy dose.
- Age
- 18 years or older
- Sex
- All sexes
- Disease stage
- Adenocarcinoma of the rectum, clinical tumor category cT1-3. On MRI the tumor is at most 4.5 cm (1.8 in) across and its lowest edge is at or below the peritoneal reflection. No distant metastases.
- Earlier treatment
- No earlier surgery for this cancer, including transanal excision of the tumor. No earlier radiation to the pelvis.
Main reasons for not taking part
- Other cancer within the past five years, except non-melanoma skin cancer and premalignant lesions such as carcinoma in situ
- Distant metastases (cM1)
- Pregnant or breastfeeding women
- Existing colostomy or ileostomy
- Not fit for radiotherapy and capecitabine, for example poor bone marrow, liver or kidney function
Read by machine on 9 November 2026.
Where in Denmark
- Aalborg University HospitalAalborg, DenmarkTaking people
- Copenhagen University Hospital, Righshospitalet and Bispebjerg HospitalCopenhagen, DenmarkTaking people
- Zealand University Hospital, NæstvedNæstved, DenmarkTaking people
- Zealand University Hospital, RoskildeRoskilde, DenmarkTaking people
- Department of Oncology, Vejle HospitalVejle, DenmarkTaking people
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Trial details
- Who runs it
- Vejle Hospital
- Trial code
- NCT04095299
- Record updated
- 8 January 2026
- Original description
In recent years, an increasing number of retrospective and prospective observational studies have indicated that a subset of rectal cancer patients may avoid surgery if they can achieve a complete response to chemoradiotherapy. Prospective trials, including the previous Danish Watchful Waiting trials (NCT00952926, NCT02438839) in early rectal cancer have demonstrated high levels of organ preservation with dose-escalation, but it is unclear whether this was primarily due to tumor stage or dose level.Read full original descriptionShow less
Randomized Trial of Standard Dose Versus High Dose of Radiotherapy in Rectal Preservation With Chemo-radiotherapy to Patients With Early Low and Mid Rectal Cancer: The Watchful Waiting 3 Trial (WW3)
In recent years, an increasing number of retrospective and prospective observational studies have indicated that a subset of rectal cancer patients may avoid surgery if they can achieve a complete response to chemoradiotherapy. Prospective trials, including the previous Danish Watchful Waiting trials (NCT00952926, NCT02438839) in early rectal cancer have demonstrated high levels of organ preservation with dose-escalation, but it is unclear whether this was primarily due to tumor stage or dose level.
The aim of the present study is to investigate if a higher dose of radiotherapy is superior compared to a standard dose in patients with early rectal cancer undergoing chemoradiotherapy with curative intent.
Inclusion: Histopathologically verified adenocarcinoma of the rectum; MDT conference finds patient a candidate for rectal resection; Clinical tumor category cT1-3; MRI findings; Maximal cross-sectional size of 4.5 cm (axial plane relative to the rectum); Lowest edge of tumor located at or below the peritoneal reflection on MRI; Performance status 0-2; Age ≥ 18 years; Eligible for radiotherapy and capecitabine according to investigator, including; Adequate function of bone marrow (neutrophils ≥ 1.5 x 10\^9/l and thrombocytes ≥ 100 x 10\^9/l); Adequate function of liver (ALAT < 2.5 x upper limit of normal, bilirubin < 2.5 x upper limit of normal); Adequate kidney function (Serum creatinine < 1.5 x upper limit of normal or measured GFR > 30 ml/min); Fertile women must present a negative pregnancy test and use secure contraceptives during and three months after treatment; Written and orally informed consent.
Exclusion: Previous surgical treatment of the present cancer, including transanal excision of tumor; Previous radiation treatment of the pelvis; Other malignant disease within the past five years except non-melanoma skin cancer and premalignant lesions such as carcinoma in situ; Distant metastases verified by imaging or biopsy, i.e. cM1; Pregnant or breastfeeding women; Existing colostomy or ileostomy.