Mucosal Biomarkers of Colorectal Cancer Risk Do Not Increase at 6 Months Following Sleeve Gastrectomy, Unlike Gastric Bypass 

Kant P, Perry SL, Dexter SP, Race AD, Loadman PM, Hull MA

Objective: We tested the hypothesis that sleeve gastrectomy (SG) is not associated with an increase in mucosal CRC biomarkers, unlike Roux-en-Y gastric bypass (RYGB).

Design and Methods: Rectal mucosa, blood and urine were obtained from morbidly obese patients (n=23) before and after (median 28 months) SG, as well as from non-obese controls (n=20). Rectal epithelial cell mitosis and apoptosis, crypt size/fission and pro-inflammatory gene expression were measured, as well as systemic inflammatory biomarkers, including C-reactive protein (CRP).

Results: The mean pre-operative body mass index in SG patients was 65.7 Kg/m(2) (24.7 Kg/m(2) in controls). Mean excess weight loss post-SG was 38.2%. There was a significant increase in mitosis frequency, crypt size and crypt fission (all p<0.01) in SG patients versus controls, as well as evidence of a chronic inflammatory state (raised CRP and mononuclear cell p65 NF?B binding), but there was no significant change in these biomarkers after SG, except CRP reduction. Macrophage migration inhibitory factor (MIF) mRNA levels were increased by 39% post-SG (p=0.038).

Conclusions: Mucosal biomarkers of CRC risk do not increase at 6 months following SG, unlike RYGB. Biomarkers of rectal crypt proliferation and systemic inflammation are increased in morbidly obese patients compared with controls.