Watch and wait approach in rectal cancer: Current controversies and future directions

Abstract

According to the main international clinical guidelines, the recommended treatment for locally-advanced rectal cancer is neoadjuvant chemoradiotherapy followed by surgery. However, doubts have been raised about the appropriate definition of clinical complete response (cCR) after neoadjuvant therapy and the role of surgery in patients who achieve a cCR. Surgical resection is associated with significant morbidity and decreased quality of life (QoL), which is especially relevant given the favourable prognosis in this patient subset. Accordingly, there has been a growing interest in alternative approaches with less morbidity, including the organ-preserving watch and wait strategy, in which surgery is omitted in patients who have achieved a cCR. These patients are managed with a specific follow-up protocol to ensure adequate cancer control, including the early identification of recurrent disease. However, there are several open questions about this strategy, including patient selection, the clinical and radiological criteria to accurately determine cCR, the duration of neoadjuvant treatment, the role of dose intensification (chemotherapy and/or radiotherapy), optimal follow-up protocols, and the future perspectives of this approach. In the present review, we summarize the available evidence on the watch and wait strategy in this clinical scenario, including ongoing clinical trials, QoL in these patients, and the controversies surrounding this treatment approach.

Keywords: Watch and wait; Rectal cancer; Clinical complete response; Organ preservation; Dose intensification

Core tip: The Watch and wait strategy in selected patients with locally-advanced rectal cancer is associated with lower morbidity and better quality of life than conventional treatment, with good cancer control. Given the growing relevance of this strategy, which is increasingly being used at international centres of reference, a comprehensive review of the available data is needed. In addition, there are several open questions and controversies about this strategy that can only be resolved by an in-depth analysis and consensus among the specialists involved in treating these patients.