[Thoughts on the watch and wait strategy of patients with rectal cancer after neoadjuvant therapy]

In 2004, Habr-Gama reported a new group of rectal cancer patients achieving clinical complete response (cCR) after neoadjuvant chemoradiotherapy, who were able to get a satisfactory curative effect after a non-operative watch and wait (W&W) strategy. Since then, W&W has attracted more and more public attention. Although results of accumulating clinical studies have shown that W&W strategy is feasible for treating part of rectal cancer patients, there is still a lack of evidence-based medical evidence. Therefore, the feasibility and safety of the strategy still need further investigation. The main focuses are on the optimized scheme of chemoradiotherapy, the timing and standard to evaluate a cCR, and the shortage of a more precise approach to judging and predicting cCR. Whether a salvage surgery is safe and feasible for local regeneration, the risk of increasing distant metastasis and long-term oncologic and functional outcomes of patients also remain uncertain. Based on the literature and the institute's experience, this paper will elaborate the current development status and existing problems of W&W and look forward to the application prospect and future challenges.