Within the lower foregut tumor community, there currently exists a high level of excitement regarding the potential use of sphincter preservation for patients with invasive adenocarcinoma of localized rectal cancer. A series of studies have suggested that there may indeed be a subset of patients who do not require a standard radical surgical procedure, most often defined as a total mesorectal excision, following a clinical complete response (cCR) to chemoradiotherapy.1 To that end, the multidisciplinary lower foregut cancer team at Memorial Sloan Kettering Cancer Center (MSKCC) have shared their experience in this issue of JAMA Oncology2 with offering patients a carefully monitored watch-and-wait strategy and compared those patients to a cohort who had a pathologic CR (pCR) following sequential preoperative therapy and total mesorectal excision. This is an important comparison because advocates of a WW approach are hoping that a cCR is a reliable surrogate for a pCR. By comparing the 5-year outcomes of the watch-and-wait cohort with a cohort who experienced a pCR following a form of standard combined modality therapy, the authors provide a helpful data set from which a multidisciplinary care team and patients can consider as part of a shared decision-making approach to clinically resectable rectal cancer. In particular, despite earlier reports from the well-designed International Watch and Wait database that most local recurrences occur within 24 months, the results of the present study with a slightly longer median follow-up period of 3.6 years suggest that local recurrence may not plateau quite so soon. In addition, although salvage therapy seems effective and intrapelvic bowel disease is well controlled, there are patients with distant recurrence. None of the current publications provide clarity on how best to avoid such a scenario. As such, the prospective, multi-institutional phase 2 trial that is being led by this MSKCC team is eagerly awaited.3 For now, unless the care team is truly multidisciplinary and thus primed to evaluate, treat, and diligently follow-up patients in a close manner, the WW approach may not be in the best interest of the patient. In such cases, hold tight because it is likely that we will have stronger prospective data that may provide a sound foundation for evidence-based recommendations on how best to identify optimal candidates and guidelines for execution of watch-and-wait care in resectable rectal cancer.
Published Online: January 10, 2019. doi:10.1001/jamaoncol.2018.5895
Corresponding Author: Charles R. Thomas Jr, MD, Department of Radiation Medicine, Oregon Health and Science University, Mail Code KPV4, 3181 SW Sam Jackson Park Rd, Portland, OR 97239-3098 (email@example.com).
Conflict of Interest Disclosures: Dr Thomas reported receiving grants from the National Cancer Institute and serving as a co-principal investigator with Dr Garcia-Aguilar on the American College of Surgeons Oncology Group Z6041 trial, which has been reported and examined a subset of patients with rectal cancer different from the subset investigated in the present study.
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