What surveillance do you recommend for a patient with locally advanced rectal adenocarcinoma who had a complete clinical response to total neoadjuvant therapy and declines to undergo surgery?  

It is important to watch these patients closely since ~15-20% will have local regrowth/recurrence that are salvageable (Dossa et al Lancet 2017). The OPRA trial, recently presented at ASCO 2020, included 324 patients treated with TNT regimens and WW if complete response. Organ preservation rates wer...