Timing for Rectal Surgery After Chemoradiotherapy

Timing for Rectal Surgery After ChST

The aim of this study is to determine whether greater rectal cancer downstaging and regression occurs when surgery is delayed to 12 weeks after completion of radiotherapy/chemotherapy compared to 8 weeks.

Hypothesis: Greater down-staging and tumor regression is observed when surgery is delayed to 12 weeks after completion of chemoradiotherapy compared to 8 weeks.

Inclusion Criteria:

• Over 18 years old
• Eastern Cooperative Oncology Group (ECOG) 0-1,
• American Society of Anesthesiologists' (ASA) score I-III
• Histological confirmation of adenocarcinoma of rectum
• T3 or T4 N0, T any N positive cancer on MRI, without metastasis on CT scan
• Undergoing preoperative radiotherapy/ chemotherapy
• Curative total mesorectal excision intended
• Written informed consent
• Patients undergoing preoperative radiotherapy should not be excluded

Exclusion Criteria:

• Patients with distant metastasis
• T1 or T2, N0 cancer on MRI
• Rectal cancer 12 cm above the dentate line
• Contraindications to MRI
• Patients previously treated of pelvic organ cancer
• Medical or psychiatric conditions that compromise the patients ability to give informed consent