Complete clinical response to neoadjuvant chemoradiotherapy in patients with rectal cancer: opinions of British and Irish specialists

Abstract

Advances in neoadjuvant treatment have highlighted the phenomenon of complete clinical response (CCR) in a proportion of patients with rectal cancer. Radical surgery may be associated with a poor functional outcome and quality of life and has a small but significant risk of mortality. This study aimed to assess opinion of colorectal surgeons on issues surrounding the question of nonoperative management in patients who demonstrate complete response after neoadjuvant therapy. A questionnaire was sent to members of the Association of Coloproctology of Great Britain and Ireland regarding investigations, clinical management, pathological assessment and oncological outcome in rectal cancer patients with a complete response to neoadjuvant chemoradiotherapy. A total of 122 consultants responded (26% response rate). Most surgeons (58%) would not consider conservative management of patients with a complete response and even more (69%) expressed that they would never discuss nonoperative management in patients with rectal cancer who are fit for curative surgery. Over 70 different combinations of investigations and imaging modalities were suggested to define a CCR. Eighty-six per cent of consultants felt that a pathology report stating no evidence of residual adenocarcinoma did not rule out the presence of tumour cells and all respondents estimated the percentage of patients with pathological complete response as < 20%. No consensus exists as to what defines a complete response and at present there is resistance to offering nonoperative management in selected patients. With improvements in neoadjuvant treatment modalities, it will be increasingly important to consider nonoperative management in the future.