Towards Response guided ADAptive Radiotherapy for organ preserving treatment of intermediate risk rectal cancer: a phase I dose finding trial

Status

Recruiting

Phases

Unknown

Study type

Interventional

Source

NL-OMON

Registry ID

NL-OMON22916

Enrollment

Registered

2020-10-23

Start date

2021-11-01

Completion date

Unknown

Last updated

2025-03-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

rectal cancer

Interventions

2, 3, 4, or 5 sequential, homogenous boost fractions of 5 Gy on the gross tumor volume (GTV) in the week following SCRT using MR-guided online adaptive radiotherapy on the MR-linac.

Eligibility

Inclusion criteria

Inclusion criteria: - Age =18; - Biopsy proven rectal adenocarcinoma; - Intermediate risk tumor, based on TNM (AJCC 8th edition) stage (T3c-d (MRF-) N0M0 or cT1-3 (MRF-) N1M0) - Mid-rectal or distal rectal tumor: lower border anteriorly not above peritoneal fold, upper border below sigmoid take-off; - Indication for neoadjuvant short course radiotherapy as judged by multidisciplinary tumor board discussion; - Fit for multimodal treatment, as judged by multidisciplinary tumor board discussion; - Written informed consent.

Exclusion criteria

Exclusion criteria: - Mucinous tumor or neuro-endocrine tumor, as defined on MRI and/or histopathology; - No residual luminal tumor after local excision; - Recurrent tumor or regrowth after previous treatment; - Extra-mesorectal pathological lymph nodes; - Planned systemic therapy (either with curative or palliative intent); - History of inflammatory bowel disease; - Prior pelvic radiotherapy; - Contraindications for MRI at 1.5T; - Orthopedic hip implants; - Pregnancy.

Design outcomes

Primary

Measure	Time frame
Maximum tolerated dose based on the incidence of dose limiting toxicity, a composite of (1) radiation toxicity grade =4 according to Common Toxicity Criteria for Adverse Events (CTCAE) version 5.0 occurring within 20 weeks after start of radiotherapy and before surgery, (2) radiation toxicity grade 3 persisting > 12 weeks after start of radiotherapy, (3) postponing of surgery > 16 weeks due to any grade of radiation toxicity and (4) post-operative complications Clavien-Dindo IIIb-IV in case of residual disease and indication for surgery.	—

Measure

Time frame

Maximum tolerated dose based on the incidence of dose limiting toxicity, a composite of (1) radiation toxicity grade =4 according to Common Toxicity Criteria for Adverse Events (CTCAE) version 5.0 occurring within 20 weeks after start of radiotherapy and before surgery, (2) radiation toxicity grade 3 persisting > 12 weeks after start of radiotherapy, (3) postponing of surgery > 16 weeks due to any grade of radiation toxicity and (4) post-operative complications Clavien-Dindo IIIb-IV in case of residual disease and indication for surgery.

—

Secondary

Measure	Time frame
Eligibility of patients, intervention acceptance rate, GTV coverage of the boost fractions, non-dose limiting radiation toxicity and postoperative complications, organ preservation rate, locoregional control, disease free survival, overall survival, late radiation toxicity, quality of life (EORTC QLQ-C30 and CR-29) and functional outcome (LARS score).	—

Contacts

Public ContactMaaike Verweij

UMC Utrecht

m.e.verweij-5@umcutrecht.nl0615295236

Outcome results

None listed

Source: NL-OMON (via WHO ICTRP)