Due to futility

The study aims to compare the incidence of acute grade 2 GI toxicity in the Control 3-D Conformal Radiotherapy compared to the Intensity Modulated Radiotherapy (IMRT) arm for locally advanced rectal cancer.

Pre-operative radiotherapy (RT) or chemo-radiotherapy (CRT) is internationally accepted as standard practice in the management of locally advanced rectal cancer.

Multiple randomised trials have proved pre-operative CRT and RT, compared to surgery alone, reduce local recurrence, even prior to optimal surgery, and may improve survival for T3 circumferential resection margin (CRM) negative patients.

This study aims to determine if 3-DCRT or IMRT result in lower incidence of grade 2 GI toxicities.

Acute toxicities will be assessed weekly during radiotherapy, and at 2 and 4 week post treatment.

Late toxicities will be assessed at 3, 6, 9, 12, 18, 24 months post treatment, and annually to 10 years.

Inclusion Criteria:

• Patients undergoing pre-operative pelvic chemo-radiotherapy for histologically confirmed rectal adenocarcinoma, with the following staging: cT3N0-2, cT4N0-2, cT(any)N1-2, cT(any)N(any) CRM at-risk [AJCC version V]
• Staging / imaging of pelvis with MRI, and CT Thorax/Abdomen
• No evidence of metastatic disease
• ECOG Performance Status 0 - 2
• Age > or equal to 18 years
• Provision of written informed consent in line with ICH-GCP guidelines

Exclusion Criteria:

• Previous radiotherapy to the pelvic region
• Patients in whom induction chemotherapy has been delivered prior to chemo- radiotherapy
• History of inflammatory bowel disease
• Previous hip replacement
• Previous bowel surgery (excluding procedures/operations which would not result in small bowel adhesions - at the discretion of the Principal Investigator)
• Patients with other syndromes/conditions associated with increased radiosensitivity
• Any other co-existing malignancies within the past 5 years other than non- melanoma skin cancer
• Pregnancy or lactation at the time of proposed randomisation
• Evidence of any other significant clinical disorder or laboratory finding that makes it undesirable for the patient to participate in the study or if it is felt by the research / medical team that the patient may not be able to comply with the protocol