LAUSR

Nonoperative management (watch and wait) is an emerging novel strategy for organ preservation in patients with rectal cancer. Nonoperative management for rectal cancer can be renamed as “surveillance with selective delayed surgery,” in which patients who achieved a clinical complete response after neoadjuvant therapy do not immediately receive surgery but undergo surveillance with an option to convert to delayed surgery when residual cancer cells develop an evident local regrowth. With improved complete response rates in total neoadjuvant therapy (TNT), physicians have more opportunities to counsel patients and decide whether to proceed with or postpone surgery. Conventional static clinical calculators or staging systems to estimate risk of recurrence are not applicable in nonoperative management in which pathologic parameters are not available and patients are expected to migrate from a nonoperative to operative management for salvage surgery. TheworkbyWeiseretalin JAMANetworkOpen 1 developedanovelclinicalcalculatorinrectalcancer treated with TNT that incorporated a principle of conditional survival to provide dynamic estimates of recurrence by timeline and by treatment type (upfront surgery or nonoperative management with/without delayed surgery). The study has high originality in incorporating a concept of time lapse in a model to allow dynamic migration of treatment strategy from nonoperative management to delayedsurgery.Thecreatedcalculatorprovidesobjectiveconditionalsurvivalestimatesofoperative vs nonoperative management at any time during follow-up. This retrospective observational study was conducted in a single comprehensive cancer center, and the authors have been taking a global leadership role in developing TNT and nonoperative management for rectal cancer. 2,3 The study cohort was well qualified with a long follow-up period under an established clinical protocol of nonoperative management including the neoadjuvant regimens, diagnostic criteria of complete response, decision to proceed with nonoperative management, and a surveillance program. 3 Another strength of the study was that all patients underwent total neoadjuvant therapy (induction systemic FOLFOX/CAPOX followed by chemoradiotherapy), current clinical practice. Decision-making in modern multidisciplinary treatment for rectal cancer needs comprehensive assessment of various risk factors such as molecular profiling (eg, microsatellite status, KRAS status), radiologic malignant features on MRI (eg, extramural venous invasion, circumferential resection margin, lateral pelvic lymph node) and posttreatment circulating tumor DNA. Further efforts are encouraged to evolve a prediction model.