Early-Stage Colon Cancer Surveillance: Pattern and Timing of Recurrence and the Role of 5-Year Surveillance

Colorectal cancer is the third most prevalent cancer among both men and women with 80% of patients having localized disease enabling curative treatments. Given the low recurrence rate in early-stage disease, there is a growing interest in reviewing follow-up protocols. The aim of this study was to assess the frequency and timing of recurrence in early-stage colon cancer, as well as recurrence patterns.

The data from all patients with colon adenocarcinoma consecutively treated with surgery at the Instituto Português de Oncologia do Porto, EPE, between January 2013 and December 2016, were retrospectively reviewed.

A total of 1,372 patients with colon cancer were submitted to surgery during the study period. From this group, 51.4% (n = 705) were early-stage colon cancers. Regarding the pathological stage, 3.5% were stage 0, 37.4% were stage I and 59.1% were stage II. The overall recurrence rate was 6.7%. When considering the group of patients without risk factors, the recurrence rate was 5.6%. The majority of recurrences occurred in the first 3 years of follow-up. The recurrence was diagnosed in the majority of patients through carcinoembryonic antigen elevation, followed by imaging exams. The presence of one or more risk factors (high nuclear grade, vascular invasion, extramural venous invasion, and perineural invasion) showed a statistically significant association with recurrence rate.

The recurrence rate was low in early-stage colon cancer, with the majority of recurrences occurring in the first 3 years. Our study results show that surveillance should be tailored according to individual risk factors.