BackgroundIn rectal cancer, watch and wait for patients with a cCR after neoadjuvant treatment has an established evidence base. However, there is a lack of consensus on the definition and... Show moreBackgroundIn rectal cancer, watch and wait for patients with a cCR after neoadjuvant treatment has an established evidence base. However, there is a lack of consensus on the definition and management of a near-cCR. This study aimed to compare outcomes in patients who achieved a cCR at first reassessment versus later reassessment.MethodsThis registry study included patients from the International Watch & Wait Database. Patients were categorized as having a cCR at first reassessment or at later reassessment (that is near-cCR at first reassessment) based on MRI and endoscopy. Organ preservation, distant metastasis-free survival, and overall survival rates were calculated. Subgroup analyses were done for near-cCR groups based on the response evaluation according to modality.ResultsA total of 1010 patients were identified. At first reassessment, 608 patients had a cCR; 402 had a cCR at later reassessment. Median follow-up was 2.6 years for patients with a cCR at first reassessment and 2.9 years for those with a cCR at later reassessment. The 2-year organ preservation rate was 77.8 (95 per cent c.i. 74.2 to 81.5) and 79.3 (75.1 to 83.7) per cent respectively (P = 0.499). Similarly, no differences were found between groups in distant metastasis-free survival or overall survival rate. Subgroup analyses showed a higher organ preservation rate in the group with a near-cCR categorized exclusively by MRI.ConclusionOncological outcomes for patients with a cCR at later reassessment are no worse than those of patients with a cCR at first reassessment. Show less
BACKGROUND: Nearly 30% of patients with rectal cancer develop local regrowth after initial clinical complete response managed by watch and wait. These patients might be at higher risk for distant... Show moreBACKGROUND: Nearly 30% of patients with rectal cancer develop local regrowth after initial clinical complete response managed by watch and wait. These patients might be at higher risk for distant metastases.OBJECTIVE: This study aimed to investigate risk factors for distant metastases using time-dependent analyses.DESIGN: Data from an international watch and wait database were retrospectively reviewed. Cox regression analysis was used to determine risk factors for worse distant metastases-free survival. Conditional survival modeling was used to investigate the impact of risk factors on the development of distant metastases.SETTING: Retrospective, multicenter database.PATIENTS: A total of 793 patients (47 institutions) with rectal cancer and clinical complete response to neoadjuvant treatment from the International Watch & Wait Database were included.MAIN OUTCOME MEASURES: Distant metastases-free survival.RESULTS: Of the 793 patients managed with watch and wait (median follow-up 55.2 mo)‚ 85 patients (10.7%) had distant metastases. Fifty-one of 85 patients (60%) had local regrowth at any time. Local regrowth was an independent factor associated with worse distant metastases-free survival in the multivariable model. Using conditional estimates, patients with local regrowth without distant metastases for 5 years (from decision to watch and wait) remained at higher risk for development of distant metastases for 1 subsequent year compared to patients without local regrowth (5-year conditional distant metastases-free survival 94.9% vs 98.4%).LIMITATIONS: Lack of information on adjuvant chemotherapy, salvage surgery for local regrowth, and heterogeneity of individual surveillance/follow-up strategies used may have affected results.CONCLUSIONS: In patients with clinical complete response managed by watch and wait, development of local regrowth at any time is a risk factor for distant metastases. The risk of distant metastases remains higher for 5 years after development of local regrowth. Show less
Background Watch and wait is a novel management strategy in patients with rectal cancer who have a clinical complete response after neoadjuvant chemoradiotherapy. Surveillance of these patients is... Show moreBackground Watch and wait is a novel management strategy in patients with rectal cancer who have a clinical complete response after neoadjuvant chemoradiotherapy. Surveillance of these patients is generally intensive, because local regrowth (with the potential for salvage) occurs in 25% of patients, and distant metastases occur in 10% of patients. It is unclear for how long these patients should be followed up. To address this issue, we did conditional survival modelling using the International Watch & Wait Database (IWWD), which is a large-scale registry of patients with a clinical complete response after neoadjuvant chemotherapy who have been managed by a watch-and-wait strategy.Methods We did a retrospective, multicentre registry study using a dataset from the IWWD, which includes data from 47 clinics across 15 countries. We selected patients (aged >= 18 years) with rectal cancer who had a clinical complete response after neoadjuvant chemotherapy, and who were subsequently managed by a watch-and-wait strategy between Nov 25,1991, and Dec 31,2015. Patients who had not achieved a clinical complete response or who had undergone any surgical procedure were excluded. The criteria used for defining a clinical complete response and the specific surveillance strategies were at the discretion of each participating centre. We used conditional survival modelling to estimate the probability of patients remaining free of local regrowth or distant metastasis for an additional 2 years after sustaining a clinical complete response or being distant metastasis-free for 1,3, and 5 years from the date of the decision to commence watch and wait. The primary outcomes were conditional local regrowth-free survival at 3 years, and conditional distant metastasis-free survival at 5 years.Findings We identified 793 patients in the IWWD with clinical complete response who had been managed by a watch-and-wait strategy. Median follow-up was 55.2 months (IQR 36.0-75.6). The probability of remaining free from local regrowth for an additional 2 years if a patient had a sustained clinical complete response for 1 year was 88.1% (95% CI 85.8-90.9), for 3 years was 97.3% (95.2-98.6), and for 5 years was 98.6% (97.6-100.0). The probably of remaining free from distant metastasis for a further 2 years in patients who had a clinical complete response without distant metastasis for 1 year was 93.8% (92.3-95.9), for 3 years was 97.8% (96.6-99.3), and for 5 years was 96.6% (94.0-98.9).Interpretation These results suggest that the intensity of active surveillance in patients with rectal cancer managed by a watch-and-wait approach could be reduced if they achieve and maintain a clinical complete response within the first 3 years of starting this approach. Copyright (C) 2020 Elsevier Ltd. All rights reserved. Show less
Dekkers, O.M.; Vandenbroucke, J.P.; Cevallos, M.; Renehan, A.G.; Altman, D.G.; Egger, M. 2019
