Cost analysis of the use of digital rectoscopy versus flexible sigmoidoscopy in rectal cancer patients undergoing watch and wait.

INTRODUCTION AND OBJECTIVE: Organ preservation strategies for rectal cancer following neoadjuvant treatment require intensive endoscopic monitoring to detect early luminal recurrence. This is termed 'Watch and Wait' (WAW). Standard protocols commonly mandate flexible sigmoidoscopy every 3-4 months for 2 years. Digital proctoscopy with the LumenEye device has been shown to be a safe alternative that can be performed in an outpatient setting without the need for sedation and with less staffing requirements. The study objective is to evaluate the economic implications of using digital proctoscopy compared with flexible sigmoidoscopy for patients with rectal cancer managed under a WAW protocol.

SETTING AND DESIGN: The study was conducted in a secondary care National Health Service (NHS) setting. A cost comparison analysis was performed over a 2 year time horizon (seven procedures per patient). 177 procedures on rectal cancer patients undergoing WAW with digital proctoscopy between August 2023 and November 2024 were included. The control group, that is, flexible sigmoidoscopy was modelled. The base case was flexible sigmoidoscopy without sedation. Scenarios using sedation were also evaluated. Costs were categorised into fixed and variable costs. A one-way sensitivity analysis, probabilistic sensitivity analysis and What-If scenarios were also performed.

OUTCOME MEASURES AND RESULTS: The primary outcome was the minimum cost difference between the two procedures. The secondary outcome measure was the robustness of the cost differences. Over 2 years, the total cost per patient was £768.92 (95% CI £656.6 to £900.7) for digital proctoscopy compared with £1,588.15 (95% CI £1458.1 to £1725.2) for flexible sigmoidoscopy without sedation. The absolute minimum cost saving per patient is £820.23 (95% CI £648.7 to £985.1). Cost savings increased to £848.94 (95% CI £677.20 to £1013.83) to £935.62 (95% CI £761.02 to £1103.08) when sedation was used in flexible sigmoidoscopy procedures. Personnel costs during the procedure and recovery phase were the dominant cost drivers for flexible sigmoidoscopy. Probabilistic sensitivity analysis and What-If scenarios confirmed the robustness of the findings, with flexible sigmoidoscopy remaining more costly.

CONCLUSION: Digital proctoscopy with the LumenEye device is a cost-saving alternative to flexible sigmoidoscopy for patients with rectal cancer on a WAW protocol. Our findings support the integration of digital proctoscopy into WAW pathways as a cost-efficient alternative within resource-constrained healthcare systems. Endoscopy service pressures are also likely to be alleviated.