Abstract 3437: Visceral abdominal fat is associated with incisional hernia occurrence after colorectal cancer surgery - the ColoCare Study
Authors: Böhm Jürgen , Nattenmüller Johanna , Pianka Frank , Gigic Biljana , Balavarca Yesilda , Stüttgen Nina , Schrotz-King Petra , Scherer Dominique , Ulrich Alexis , Diener Markus K. , Kauczor Hans-Ulrich , Ulrich Cornelia M. 
Published: August 2015

Abstract
Introduction:
Abdominal surgery for tumor removal is essential in the treatment of colorectal cancer (CRC). Incisional hernias (IH) are a common long-term complication after abdominal surgery with an incidence of 9-20%. Several risk factors for developing IH have been identified, including a higher body mass index (BMI). However, it is unknown whether specific abdominal fat compartments, such as subcutaneous or visceral fat, are associated with IH occurrence. Thus, the aim of this study was to explore whether subcutaneous or visceral fat compartments might be predictors of IH occurrence in CRC patients after oncologic surgery.
Methods:
This study was conducted on 139 newly-diagnosed colorectal cancer patients of the prospective cohort study ColoCare (NCT, Heidelberg, Germany) who underwent oncologic surgery at the surgical clinics of the University Hospital Heidelberg. Self-administered questionnaires were used to assess hernia occurrence at 3, 6, 12 and 24 months post-surgery. BMI was calculated (kg/m^2) and abdominal fat compartments were assessed by routine computed tomography (CT) scans. The total (TFA), subcutaneous (SFA) and visceral fat area (VFA) was quantified as area (cm^2) on level L3/L4 and L4/L5. Before analyses, fat data were grouped into two categories (high vs. low) by the median. Logistic regression was used to measure the association between BMI, TFA, SFA or VFA and IH occurrence.
Results:
Patients were on average 61.3 (±12.5) years old with 37% being female and 63% being male. Patients were diagnosed with either colon/rectosigmoid (53%) or rectal (47%) primary cancer. CT data on abdominal fat compartments were available for 56% (n = 80) of patients as CT scans were not performed on every subject during clinical routine. BMI was a statistically significant predictor of IH occurrence after adjusting for gender and age (Wald p-value &lt;0.001, OR = 1.19). Of all fat values, only VFA on level L3/L4 was statistically significant associated with IH occurrence after adjusting for gender and age (Wald p-value &lt;0.05, OR = 2.36), while TFA and SFA on level L3/L4 and all level L4/L5 fat values were not associated with IH occurrence.
Conclusion:
Our findings underline BMI as a known predictive risk factor for IH. In addition, our study newly identified visceral, but not total or subcutaneous fat, as risk factors for IH. Further studies with an increased sample size are needed to test these associations in subgroups of patients, e.g. by gender or surgical procedures. In the future, these findings may help to preoperatively decide on prophylactic interventions, such as intraoperative mesh implantations, to reduce hernia occurrence.
Citation Format: Jürgen Böhm, Johanna Nattenmüller, Frank Pianka, Biljana Gigic, Yesilda Balavarca, Nina Stüttgen, Petra Schrotz-King, Dominique Scherer, Alexis Ulrich, Markus K. Diener, Hans-Ulrich Kauczor, Cornelia M. Ulrich. Visceral abdominal fat is associated with incisional hernia occurrence after colorectal cancer surgery - the ColoCare Study. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3437. doi:10.1158/1538-7445.AM2015-3437