Organ Preservation in Rectal Cancer: Contact X-ray Brachytherapy vs Extending the Waiting Interval and Local Excision (OPAXX)
Organ Preservation, Rectal Cancer, Quality of Life
About this trial
This is an interventional treatment trial for Organ Preservation focused on measuring Organ preservation, Rectal cancer, (Chemo)radiation, Local excision, Contact x-ray brachytherapy, TAMIS
Eligibility Criteria
Inclusion Criteria: histologically verified adenocarcinoma above the dentate line and within 10cm of the anal verge; neoadjuvant short-course radiotherapy for patients with 1) IRC and delayed response evaluation according to the Dutch national guidelines (cT1-3, cN1-2 lymph nodal status, no involved MRF or cT3c-d, N0-1 lymph nodal status without pres-ence of significant distant metastases) without full dose chemotherapy in the inter-val (e.g. Rapido-scheme) or 2) LARC due to comorbidity or frailty; OR neoadjuvant long-course radiotherapy (chemoradiation) for patients with 1) LARC according to the Dutch national guidelines (cT4 tumour, cN2 lymph nodal status, lateral lymph node involvement, and/or involved MRF, without the presence of significant distant metastases) or 2) early rectal cancer or IRC and a strong wish for organ preservation; clinically near-complete response or a small residual tumour mass <3 cm; technically feasible to perform both treatment options (contact x-ray brachytherapy or local excision); age >18 years; written informed consent. Exclusion Criteria: neoadjuvant or induction chemotherapy prior or adjacent to (chemo)radiation, e.g. patients with a Rapido or M1-scheme are not eligible; radiation dose >50.4 Gy or boost dose on the primary tumour; presence of suspicious lymph nodes (yN1/N2) at first response evaluation; residual tumour ≥ 3cm or over half of the circumference of the rectal lumen; patients who are unable to undergo contact x-ray brachytherapy or local excision; patients who cannot tolerate a completion- or salvage-TME because of comorbidity or frailty;
Sites / Locations
- Medical Center LeeuwardenRecruiting
- Radbouw University Medical CentreRecruiting
- Catharina HospitalRecruiting
- Antoni van LeeuwenhoekRecruiting
- Deventer HospitalRecruiting
- IsalaRecruiting
- Ijsselland HospitalRecruiting
Arms of the Study
Arm 1
Arm 2
Experimental
Experimental
Contact x-ray brachytherapy
Extending the waiting interval, with or without local excision
Contact x-ray brachytherapy will be given applied after randomisation with a maximum interval of 14 weeks after finishing the neoadjuvant (chemo)radiation. Contact x-ray brachytherapy consists of three fractions of 30Gy per fraction applied to the tumour, with a 2 week interval between each boost. Response evaluation takes place every 3 months thereafter. Patients in whom a clinical complete response is detected during follow-up are offered a watch-and-wait approach; patients in whom an incomplete response or disease progression is noted, completion or salvage TME-surgery is advised.
The waiting interval will be extended with 6-8 more weeks after the first response evaluation, followed by a second (or third in case of ongoing response) re-assessment. Patients with a clinical complete response at the time of the second (or third) response evaluation will be offered a watch-and-wait approach without any surgical treatment. Patients with a remaining small lesion will be offered transanal local excision. Depending on the final pathological staging after local excision, patients are categorized as low-risk or high-risk, and will be offered a watch-and-wait strategy or completion TME-surgery, respectively.