Biography
Prof. Sun Myint earned his bachelor’s degree in 1972 at IM (2) Yangon, Burma. In 1983, he was appointed as a clinical scientist for the Medical Research Council’s Neutron trial project, where he chaired the colorectal sub-group until 1995. His main area of focus in research is the treatment of rectal malignancies. He pioneered contact X-ray brachytherapy (Papillon) in the United Kingdom and began treating patients in Clatterbridge in 1993. His team has treated over 3000 individuals with the Papillon approach, the world’s biggest cohort of patients.
Background
Surgery is the standard of care for advanced rectal cancer. Usually, EBCRT with oral capecitabine if offered prior to surgery. Nearly half can achieved clinical complete response(cCR) and we could adopt ‘watch and wait’ strategy. About 25% of patients who achieved cCR will develop local regrowth needing salvage surgery and actual organ preservation rate is usually below 50%. Radiation dose escalation with Contact Xray brachytherapy (CXB) can improve organ preservation rates. We share our experience from randomised phase 3 trial OPERA (Organ Preservation in Early Rectal Adenocarcinoma) to evaluate if non-surgical treatment with Watch and wait is possible for locally advanced rectal cancer.
Methods
From June 2015 to June 2020 148 patients with cT2cT3cN0/cN1 <5cm rectal cancer patients were randomised to either Arm A (Standard of Care) external beam chemo-radiotherapy [EBCRT] (45Gy/25#/5weeks) + capecitabine 825mg/m2 +EBRT boost(9Gy) or Arm B (experimental arm) EBCRT + CXB (90 Gy/3 #/4 weeks).
Results
At median FU of 38.2 months, for patients with tumours of 3 cm or larger, 3-year organ preservation rates were 55% (95% CI 41–74) in group A versus 68% (54–85) in group B (HR 0·54, 95% CI 0·26–1·10; p=0·11). For patients with tumours less than 3 cm in diameter, 3-year organ preservation rates were 63% (95% CI 47–84) in group A versus 97% (91–100) in group B (HR 0·07, 95% CI 0·01–0·57; p=0·012).
Conclusion
Our data from randomised trial OPERA suggested that even for rectal tumour cT2/cT3 cN0/cN1 larger than 3 cm, organ preservation with watch and wait strategy is feasible and safe. Patients who are not fit for surgery or those who wish to avoid a stoma should be offered non-surgical treatment with EBCRT and CXB boost. Patients should be aware of this alternative treatment option.