Clinical outcome of neoadjuvant chemoradiation in locally advanced rectal cancer at a tertiary hospital

Objectives: To review the clinical outcome of locally advanced rectal cancer treated with neoadjuvant chemoradiation followed by definitive surgery with or without adjuvant chemotherapy and to elucidate the prognostic factors for treatment outcome. Methods: This historical cohort study was conducted at a tertiary public hospital in Hong Kong. All patients who had undergone neoadjuvant chemoradiation for locally advanced rectal cancer in our department from November 2005 to October 2014 were recruited. Local recurrence-free survival, distant metastasis free survival, disease free survival, and overall survival of patients were documented. Results: A total of 135 patients who had received neoadjuvant chemoradiation during the study period were reviewed. There were 130 patients who had completed neoadjuvant chemoradiation and surgery. The median follow-up time was 35.1 months. The 3- and 5-year local recurrence free survival, distant metastasis free survival, disease free survival, as well as overall survival rates were 91.8% and 86.7%, 73.9% and 72.1%, 70.1% and 64.6%, as well as 86.5% and 68.4%, respectively. The rate of pathological complete response was 13.8%. The T and N downstaging rate was 49.2% and 63.1%, respectively. The rate of conversion from threatened circumferential resection margin to clearance of margin was 90.6%. Of the 42 cases that were initially deemed to require abdominal perineal resection, 15 (35.7%) were converted to sphincter-sparing surgery. Conclusions: The treatment outcome of neoadjuvant chemoradiation for locally advanced rectal cancer was comparable with overseas data in terms of local control rate and overall survival. This strategy may increase the chance of achieving a clear surgical margin by downstaging the tumour, especially in patients who presented with threatened circumferential margin.