A significant relationship between visceral obesity and anastomotic leakage was found, which indicates that visceral obesity could be a risk factor in surgery for colon cancer.
Surgery for colon cancer could be determined through a new risk factor, as visceral obesity (VO) was found to have a significant relationship with anastomotic leakage (AL), according to a review published in Frontiers in Oncology.
AL is a common postoperative complication in surgery for colorectal cancer (CRC), with an incidence rate of 1.2% to 14.9% in patients with CRC resection. Decreasing the incidence of AL is reliant on eliminating risk factors for AL. An association between obesity and postoperative complication technical challenges has been found in the past. The primary goal of this review was to “incorporate results of the relevant comparative studies to examine the link between VO and AL following CRC surgery” as current studies have previously lacked the statistical power to do so.
The authors searched the PubMed, MEDLINE, and Embase databases for studies that investigated the association between VO and AL after surgery for CRC. Studies from the databases’ inception to November 1, 2022, were searched. Studies were included if they discussed the association between VO and AL after surgery for CRC; discussed VO groups and non-VO groups; were retrospective, prospective, or cohort studies; had a clear definition of VO; had clear data; reported odds ratio (OR); and had a primary aim of comparing morbidity of AL in both VO and non-VO groups.
Data were extracted from all the included studies. The primary aim was to “combine the result of the comparative studies to determine the relationship between VO and AL after CRC surgery.” The Newcastle-Ottawa Scale was used to evaluate the quality of the studies.
There were 7 studies included in the final analysis that were published between 2006 and 2021, and the study population included 1035 patients with VO and 1101 patients with non-visceral obesity, 87 (8.41%) of whom had VO associated with AL. There were 4 studies from Asia, 1 from North America, and 2 from Europe. All studies used at least 1 of either body mass index (BMI) or visceral fat area (VFA) to calculate obesity.
A fixed-effect model of the 7 studies found that the OR of patients with VO compared with those without VO was 2.15 (95% CI, 1.46-3.15) with the difference between the groups being statistically significant. The fixed-effect model of the prospective studies found that the OR of patients with VO compared with those without was 3.25 (95% CI, 1.71-6.17). A fixed-effects model for the retrospective studies found that the OR was 1.70 (95% CI, 1.06-2.75).
Patients were found to have a higher incidence of AL if they were in the colon cancer group (OR, 2.88; 95% CI, 1.38-5.99) compared with those in the rectal group (OR, 2.74; 95% CI, 1.13-6.65). The 4 Asian studies also found higher morbidity due to AL (OR, 2.79; 95% CI, 1.35-5.78) compared with the other studies, leading the researchers to conclude that VO is good measure to include in a morbidity assessment due to AL in Asian patients.
There were some limitations to this study. The final result of the review could be influenced by confounding factors due to some studies being retrospective. A stratified analysis was performed based on the different cancer foci and different ethnicities presented in the studies. Different studies could have different VFA cutoffs. The relationship between obesity and AL across different surgeries could not be evaluated. Additionally, the analysis only included a small number of studies.
The researchers concluded that VO and AL have a significant relationship, and the incidence of AL after surgery for CRC was high in patients with VO. This finding determines a valid risk factor for patients undergoing surgery for CRC.
Yu L, Wu W, Xia S, Li Y, Xu Z. Visceral obesity and anastomotic leakage rates in colorectal cancer: a systematic review and meta-analysis. Front Oncol. Published online August 21, 2023. doi:10.3389/fonc.2023.1224196