LETTER TO THE EDITOR
|Year : 2017 | Volume
| Issue : 4 | Page : 323-324
Mini gastric bypass: Un-answered questions
Center for Bariatric and Metabolic Surgery, Wockhardt Hospital, Mumbai, Maharashtra, India
|Date of Submission||18-Jan-2017|
|Date of Acceptance||20-Feb-2017|
|Date of Web Publication||5-Sep-2017|
Center for Bariatric and Metabolic Surgery, Wockhardt Hospital, Mumbai, Maharashtra
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Goel R. Mini gastric bypass: Un-answered questions. J Min Access Surg 2017;13:323-4
Scientific community had its share of controversies in the past, and many bruised individuals ultimately proved their mettle through sheer brilliance of their concept or work. Although compelling arguments have been made for acceptance by national associations by Mahawar et al., many un-answered questions still remain.
The mini gastric bypass (MGB) surgery started by Dr. Rutledge  in 1997 became controversial as many patients were re-operated  in adjacent referral centres for reflux, bile gastritis, mal-nourishment and intractable ulcers. This not only highlighted the low follow-up rate but also the under-reported low reflux rate in the original study.
MGB remains a loop gastrojejunostomy, similar to Mason's loop gastric bypass or Billroth II, but attempts are made to distance MGB from them, based on the hypothesis that a long and narrow gastric tube will not result in bile reflux and associated carcinoma risk.
Unfortunately, even 20 years later, none of the published studies were designed to assess reduced reflux/neoplasm potential as an end point after MGB.
In a recent study by Chevallier et al., they have mentioned that Barrett's oesophagus and gastro-oesophageal reflux disease are contraindications for MGB, while most continue to recommend MGB for reflux disease. In the same study, seven post-MGB biliary reflux patients were converted to roux en Y gastric bypass (RyGBP) at ~2 years with spectacular effect on biliary reflux while patients continued to maintain their weight. Although the author(s) stated that bile was present in stomach and not in the oesophagus, they have also reported oesophageal foveolar hyperplasia (sign of biliary reflux) in 17.1%. This high percentage of histopathological changes seen on selectively endoscoped patients (17/36) as early as 2 years after MGB requires further and continued investigation as reflux-related damage may remain asymptomatic in majority of patients. Kular et al. have reported bile reflux in only 2% (n = 18) though endoscopy was done in symptomatic patients only. Thus, no attempt has been made to identify post-MGB asymptomatic bile reflux. Even Mahawar et al. have mentioned that biliary reflux will lead to a higher incidence of histological gastritis, which may not always translate into adverse symptomatic outcome.
In a recent randomised control trial comparing Billroth II with RyGBP, Csendes et al. found significant histological variation, at mean 15.5 years follow-up, in oesophagus (50%:10%), stomach (80%:0%) and Barrett's oesophagus (25%:3%).
MacDonald and Owen. have reported 3 fold increase in risk of proximal gastric pouch cancer after Billroth II surgery. In MGB studies, apparent comparisons are drawn with RyGBP while Houghton et al. have found RyGBP as the most effective anti-reflux procedure resulting in regression of short- and long-segment Barrett's oesophagus.
The main concern in oesophagogastric neoplasms after bariatric procedures is the delay in diagnosis because the symptoms may be attributed to the effects of surgery, requiring long-term follow-up, with periodic endoscopic surveillance. However, most of the MGB studies have reported extremely small post-operative endoscopic rates of <10% primarily done in symptomatic patients with intent to diagnose and not for surveillance.
Although no studies have reported post-MGB protein requirement, it can be safely assumed that it will be higher than RyGBP, which is reportedly 1.1 g/kg ideal body weight.
MGB studies have reported that patient experienced higher frequency of oil stool passage and diarrhoea, related to the short bowel effect  and higher mal-absorptive component than RyGBP.
Indians consume 50–60 g proteins daily and most are derived from cereals, which are poor source of proteins (10%). If 42% of meat-eating Caucasian population have low protein levels 1 year after MGB, protein deficiency in cereal-eating Indian patients is expected to be higher. Kular et al. have reported protein deficiency in only 2 of 1054 patients.
Informed consent remains a major issue even with surgeons performing MGB; it is not clear whether risk (theoretical) of cancer should be informed to young patients and RyGBP to be offered as an option.
It raises two issues – first, was the patient/family informed of probable cancer risk 20–25 years later and the second is acceptance of cancer risk associated with MGB by surgeons doing it. Ethical issue of ill-informed patient undergoing a surgery with potential risk of gastric stump/oesophageal carcinoma is too serious and cannot be wished away.
Considering lack of scientific authentication of the premise/hypothesis that vertical gastric transection will avoid reflux and related cancer potential, MGB should be considered an experimental/evolving procedure. Better organised studies are required before surgery can be offered in clinical practice.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| ¤ References|| |
Mahawar KK, Kumar P, Carr WR, Jennings N, Schroeder N, Balupuri S, et al.
Current status of mini-gastric bypass. J Minim Access Surg 2016;12:305-10.
Rutledge R. The mini-gastric bypass: Experience with the first 1,274 cases. Obes Surg 2001;11:276-80.
Johnson WH, Fernanadez AZ, Farrell TM, Macdonald KG, Grant JP, McMahon RL, et al.
Surgical revision of loop (“mini”) gastric bypass procedure: Multicenter review of complications and conversions to Roux-en-Y gastric bypass. Surg Obes Relat Dis 2007;3:37-41.
Chevallier JM, Arman GA, Guenzi M, Rau C, Bruzzi M, Beaupel N, et al.
One thousand single anastomosis (omega loop) gastric bypasses to treat morbid obesity in a 7-year period: Outcomes show few complications and good efficacy. Obes Surg 2015;25:951-8.
Kular KS, Manchanda N, Rutledge R. A 6-year experience with 1,054 mini-gastric bypasses-first study from Indian subcontinent. Obes Surg 2014;24:1430-5.
Mahawar KK, Carr WR, Balupuri S, Small PK. Controversy surrounding 'mini' gastric bypass. Obes Surg 2014;24:324-33.
Csendes A, Burgos AM, Smok G, Burdiles P, Braghetto I, Díaz JC. Latest results (12-21 years) of a prospective randomized study comparing Billroth II and Roux-en-Y anastomosis after a partial gastrectomy plus vagotomy in patients with duodenal ulcers. Ann Surg 2009;249:189-94.
MacDonald WC, Owen DA. Gastric carcinoma after surgical treatment of peptic ulcer: An analysis of morphologic features and a comparison with cancer in the nonoperated stomach. Cancer 2001;91:1732-8.
Houghton SG, Romero Y, Sarr MG. Effect of Roux-en-Y gastric bypass in obese patients with Barrett's esophagus: Attempts to eliminate duodenogastric reflux. Surg Obes Relat Dis 2008;4:1-4.
Scozzari G, Trapani R, Toppino M, Morino M. Esophagogastric cancer after bariatric surgery: systematic review of the literature. Surg Obes Relat Dis 2013;9:133-42.
Moize V, Geliebter A, Gluck ME, Yahav E, Lorence M, Colarusso T, et al.
Obese patients have inadequate protein intake related to protein intolerance up to 1 year following Roux-en-Y gastric bypass. Obes Surg 2003;13:23-8.
Lee WJ, Ser KH, Lee YC, Tsou JJ, Chen SC, Chen JC. Laparoscopic Roux-en-Y vs. mini-gastric bypass for the treatment of morbid obesity: A 10-year experience. Obes Surg 2012;22:1827-34.
National Sample Survey, 5, 25; Report No. 513 (61/1.0/6): Nutritional Intake in India, 2004-2005.
Luger M, Kruschitz R, Langer F, Prager G, Walker M, Marculescu R, et al.
Effects of omega-loop gastric bypass on Vitamin D and bone metabolism in morbidly obese bariatric patients. Obes Surg 2015;25:1056-62.