Systematic review and meta-analysis on outcomes of salvage therapy in patients with tumour recurrence during ‘watch and wait’ in rectal cancer

Abstract

Introduction The ‘watch and wait’ approach has recently emerged as an alternative approach for managing patients with complete clinical response in rectal cancer. However, less is understood whether the intervention is associated with a favourable outcome among patients who require salvage therapy following local recurrence. Materials and methods A comprehensive systematic search was performed using EMBASE, PubMed, MEDLINE, Journals@Ovid as well as hand searches; published between 2004 and 2018, to identify studies where outcomes of patients undergoing watch and wait were compared with conventional surgery. Study quality was assessed using the Newcastle–Ottawa assessment scale. The main outcome was relative risks for overall and disease specific mortality in salvage therapy. Results Nine eligible studies were included in the meta-analysis. Of 248 patients who followed the watch and wait strategy, 10.5% had salvage therapy for recurrent disease. No statistical heterogeneity was found in the results. The relative risk of overall mortality in the salvage therapy group was 2.42 (95% confidence interval 0.96–6.13) compared with the group who had conventional surgery, but this was not statistically significant (P > 0.05). The relative risk of disease specific mortality in salvage therapy was 2.63 (95% confidence interval 0.81–8.53). Conclusion Our findings demonstrated that there was no significant difference in overall and disease specific mortality in patients who had salvage treatment following recurrence of disease in the watch and wait group compared with the standard treatment group. However, future research into the oncological safety of salvage treatment is needed.

Watch and wait approach in rectal cancer: Current controversies and future directions

“…In the OnCoRe project[ 104 ], 88% of patients with non-metastatic local regrowths were salvaged, a slightly higher rate than reported by Kong et al[ 162 ] (83.8%) and Smith et al[ 163 ] (85%), and well above the 68.4% rate described by On et al[ 164 ] and the 69% rate reported in the International Watch and Wait Database[ 107 ]. Moreover, the salvage rate in the OnCoRe study were close to those described by Chadi et al[ 165 ] (89%) and by the Habr-Gama group (90%)[ 161 ] (Table 2 ).…”

“…In the longer term, the Habr-Gama group reported a 5-year OS of 63.3% in patients who underwent salvage surgery[ 166 ], substantially less than the 85% reported in the International Watch and Wait Database[ 107 ]. On et al[ 164 ] found no significant differences in survival rates between salvage and upfront surgery (92.3% vs 92.9%, respectively) (Table 2 ).…”

Unintended Consequences of Treating Early Rectal Cancers for Complete Clinical Response with Chemoradiotherapy

“…Considerable information is available on the risk of distant metastases, intraluminal regrowth and subsequent surgical salvage [52]. In this meta-analysis, the relative risk of overall mortality in the salvage therapy group was 2.42 (95% CI 0.96-6.13) compared with the group who had conventional surgery, but this was not statistically significant (p > 0.05).…”

“…Other small institutional retrospective studies [46,47], propensity score-matched cohort analyses [48] and modest population databases (less than 5000 patients [49] support the strategy). There have been several meta-analyses [50][51][52]. We identified few prospective [17] and no relevant randomized trials.…”

Surgical Treatment of Low-Lying Rectal Cancer: Updates

“…Recent systematic reviews and meta-analyses have concluded that although the local recurrence rate of the watch-and-wait group could be higher than in the TME group when promptly treated by salvage therapy, the watch-and-wait strategy could achieve similar oncologic outcomes as the TME approach. Salvage surgery (APR, LAR, TaTME) is possible in 83.8% of patients who develop a tumor regrowth with the “watch-and-wait” approach with no difference in overall survival and disease-free survival between patients who received immediate surgery without differences in relative risk of overall mortality and relative risk of disease-specific mortality [ 122 , 171 , 172 ].…”