Published online Sep 27, 2021. doi: 10.4240/wjgs.v13.i9.1012
Peer-review started: February 24, 2021
First decision: May 13, 2021
Revised: June 3, 2021
Accepted: August 2, 2021
Article in press: August 2, 2021
Published online: September 27, 2021
Processing time: 206 Days and 0.2 Hours
Optimal surveillance strategies for stage III colorectal cancer (CRC) are lacking, and intensive surveillance has not conferred a significant survival benefit.
To examine the association between surveillance intensity and recurrence and survival rates in patients with stage III CRC.
Data from patients with pathologic stage III CRC who underwent radical surgery between January 2005 and December 2012 at Asan Medical Center, Seoul, Korea were retrospectively reviewed. Surveillance consisted of abdominopelvic computed tomography (CT) every 6 mo and chest CT annually during the 5 year follow-up period, resulting in an average of three imaging studies per year. Patients who underwent more than the average number of imaging studies annually were categorized as high intensity (HI), and those with less than the average were categorized as low intensity (LI).
Among 1888 patients, 864 (45.8%) were in HI group. Age, sex, and location were not different between groups. HI group had more advanced T and N stage (P = 0.002, 0.010, each). Perineural invasion (PNI) was more identified in the HI group (21.4% vs 30.3%, P < 0.001). The mean overall survival (OS) and recurrence-free interval (RFI) was longer in the LI group (P < 0.001, each). Multivariate analysis indicated that surveillance intensity [odds ratio (OR) = 1.999; 95% confidence interval (CI): 1.680–2.377; P < 0.001], pathologic T stage (OR = 1.596; 95%CI: 1.197–2.127; P = 0.001), PNI (OR = 1.431; 95%CI: 1.192–1.719; P < 0.001), and circumferential resection margin (OR = 1.565; 95%CI: 1.083–2.262; P = 0.017) in rectal cancer were significantly associated with RFI. The mean post-recurrence survival (PRS) was longer in patients who received curative resection (P < 0.001). Curative resection rate of recurrence was not different between HI (29.3%) and LI (23.8%) groups (P = 0.160). PRS did not differ according to surveillance intensity (P = 0.802).
Frequent surveillance with CT scan do not improve OS in stage III CRC patients. We need to evaluate role of other surveillance method rather than frequent CT scans to detect recurrence for which curative treatment was possible because curative resection is the important to improve post-recurrence survival.
Core Tip: This is a retrospective study to evaluate the association between surveillance intensity and recurrence and survival rates in patients with stage III colorectal cancer (CRC). The overall survival (OS) and recurrence-free interval (RFI) was longer in the low intensity group. Post-recurrence survival (PRS) did not change according to surveillance intensity. Therefore, frequent postoperative imaging studies do not improve OS or RFI in patients with stage III CRC. However, in high-risk patients, early detection of recurrence improves the chance of curative resection, which may improve PRS.