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
Optimal surveillance strategies for stage III colorectal cancer (CRC) are lacking, and intensive surveillance has not conferred a significant survival benefit.
Evaluating appropriate surveillance intensity would be helpful to improve oncologic outcomes or decrease un-necessary imaging studies during surveillance.
We examined 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 pe
Among 1888 patients, 864 (45.8%) were in HI group. The HI group had more advanced T and N stage (P = 0.002, 0.010, each). A high degree of malignant differentiation was more common in the HI group than in the LI group (P = 0.027). Perineural invasion (PNI) was significantly 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 was negatively associated with RFI [odds ratio (OR) = 1.999; 95% confidence interval (CI): 1.680–2.377; P < 0.001] and OS [OR = 1.531, 95%CI: 1.295–1.808; P < 0.001]. The mean post-recurrence survival (PRS) was significantly 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 postoperative surveillance with CT scan alone do not improve OS and RFI. Curative resection is the most important factors to improve PRS and we need to find a way to increase curative treatment of recurrent disease via optimal surveillance.
Role of other imaging modalities according to risk of recurrence would be evaluated rather than increasing surveillance frequency to improve oncologic outcomes.