Timing and Frequency of Surveillance Colonoscopies After Resection for Colorectal Cancer in Queensland, Australia: A Retrospective 10-Year Analysis

Objective

To compare the timing intervals of surveillance colonoscopies after resection for colorectal cancer with recommendations in the Australian Clinical Practice Guidelines for Surveillance Colonoscopy.

Study Design

A retrospective, observational study.

Data Sources

Adults who had a resection for colorectal cancer from the Costs of Surviving Cancer—Queensland Study (COS-Q), which is a retrospective population-based cohort study of all individuals diagnosed with a primary cancer from 2005 to 2015.

Results

In total, 7265 patients that underwent resection of colorectal cancer were included for analysis. Most patients had a pre-operative colonoscopy (6636, 87.6%) while 899 patients (12.4%) had no pre-operative colonoscopy. 82.1% of patients had their first surveillance colonoscopy as recommended by the Guidelines. In contrast, after the first post-operative surveillance colonoscopy without polypectomy, 978 of 1015 (96.4%) had a second surveillance colonoscopy early by at least 6 months. Thirty seven (1.7%) had the surveillance colonoscopy on time or later than recommended. Being female or having a pre-operative colonoscopy was associated with an early second surveillance colonoscopy (odds ratio 2.2, p < 0.05). Early surveillance colonoscopies incurred costs up to AU$3.78 million.

Conclusions

Most post-resection surveillance colonoscopies for patients with colorectal cancer are performed earlier than recommended. Since colonoscopies in patients at low risk of cancer recurrence were generally performed too early, there is evidence of the potential overuse of healthcare resources and the opportunity to improve hospital efficiency.