As we all get vaccinated, COVID-19 is finally coming under control. Once again, we will be able to meet in person, debate face-to-face, and settle our differences over dinner and perhaps a drink or two. That doesn’t mean, however, that our Great Debates should stop. In fact, this month we are pitting two debaters, both long-time friends of mine and, amazingly, each other, who have been arguing virtually on every online forum during the pandemic. Their debate is on what the best initial anastomotic bariatric treatment may be: the Roux-en-Y gastric bypass (RYGB) or the one-anastomosis gastric bypass (OAGB).

This is not a new debate in the United States. It has been going on for more than 20 years, ever since the mini gastric bypass was first introduced. At first, it was a political battle and not based on legitimate data, but hopefully time has changed all that. Now, the debate should be over interpretation of the data; that is, interpretation of a multitude of studies performed outside the United States, because our societies have previously failed to approve the use of any form of the mini gastric bypass. Consequently, insurance companies did not reimburse it, essentially blocking legitimate studies in the United States.

As you will see in this month’s debate, our two highly respected and clinically experienced surgeons practice in very different settings (university vs. private practice) and come to very different conclusions from their interpretation of the same available data. Is one right and the other wrong? Can we even answer the question up for debate or is it time to conduct our own well-structured studies in the United States to possibly put this argument to rest?

I am sure our debaters will excite some of you to voice your own opinions on this subject. I would encourage you to follow up with us at General Surgery News, just as many of you have done with our previous debates like the safe cholecystectomy debate. We can only make progress by agreeing to disagree and listening to the other side’s opinions. So, let the debate begin!

The Roux-en-Y Gastric Bypass Is the Superior Operation

The surgical approach to obesity management encompasses a wide spectrum of procedures. Metabolic surgeons face a daily challenge of choosing the optimal bariatric operation without clear-cut guidance or a definite algorithm. This procedure selection dilemma exists between the Roux-en-Y gastric bypass (RYGB) and the mini or one-anastomosis gastric bypass (MGB/OAGB). Which is the better operation and why?

Interestingly, the Roux gastrojejunostomy was introduced in 1977, to resolve bile pouch gastritis in the previously described loop gastrojejunostomy configuration.¹ Histologically, there were pouch and anastomotic abnormalities in 86% to 91% of the loop configuration patients (even when an entero-enterostomy was added).² While the current MGB/OAGB adopters managed to shift attention from bile gastritis to the “lack” of bile esophagitis in MGB/OAGB, the basis of the problem of why the Roux was created is still there in the current loop configuration.

Could this inflammation lead to cancer? In a Japanese study, 417 patients developed gastric stump carcinoma after Billroth II reconstruction when partial gastrectomy was performed for benign causes (time interval, 33.9 years). Although it might not be appropriate to consider the Billroth II reconstruction itself to be oncogenic, the study concludes that gastric stump carcinoma “may come from gastrectomy-relating mechanisms after gastrectomy for original benign diseases.”³ Bile reflux is not as benign as it is advertised, and only time will tell. Time is a test that surely the RYGB has passed. While a few cases of cancer have been reported after RYGB, they remain small relative to the very high denominator of the RYGBs that have been performed over the past four decades. Additionally, while MGB/OAGB surgeons constantly undermine pathologic bile esophagitis, 45% (n=742) of the surveyed surgeons reported revising it at least once for bile reflux.⁴

Safety, a major determinant in choosing the ideal bariatric procedure, continues to be a vague matter within the MGB/OAGB community. Luckily, the long-term safety of MGB/OAGB has been compared to RYGB in the randomized controlled YOMEGA trial (with several MGB/OAGB pioneers on the design team).⁵ The MGB/OAGB had a serious complication rate of 36% (compared with 20% for RYGB) and an unforgiving 7.7% rate of malnutrition. Critics of the YOMEGA trial attributed these higher malnutrition rates to a fixed MGB/OAGB biliopancreatic (BP) length of 200 cm used in the trial. Being a malabsorptive procedure, the MGB/OAGB efficacy depends on this longer BP length. Can MGB/OAGB maintain a competitive, noninferior efficacy if the BP limb is shorter or if a percentage (rather than a fixed segment) of the total bowel length is bypassed? Of course not. The “defective” design of a wider gastrojejunostomy, smaller reservoir, and absence of pylorus added to a longer BP limb is a recipe for metabolic deficiencies with incidences of anemia of 44%, hypoalbuminemia of 32%, and hypocalcemia of 19% over a period of five years, compared with 17%, 15% and 8%, respectively, for RYGB.⁶

One can only hope that this humble long-term MGB/OAGB safety profile is counterbalanced by a safer perioperative portfolio. In principle, the one-anastomosis MGB/OAGB should be safer than the two anastomoses in RYGB, but the data show otherwise.^5,6 The MGB/OAGB is falsely publicized as a technically feasible operation, while in reality, it seems to be harder to teach and reproduce—both crucial features for the spread of any successful operation. Furthermore, if the MGB/OAGB is that easy and that perfect, why the emergence of the various modifications of it? Although these deviations are present in the RYGB, they are not surgery-defining as in MGB/OAGB.

While the MGB/OAGB is marketed as the impeccable procedure and the solution for every problem, the above characteristics pin it as an imperfect one—thus a non-endorsement by the American Society of Metabolic and Bariatric Surgeons, and a withdrawal of endorsement from the French National Authority of Health. The discrepancy between adopters’ claims and the reality witnessed by the governing institutes is a projection of one fact: lack of transparency.

This non-endorsement leads to lack of reimbursement by insurance companies, but most importantly, to a nonexistence of MGB/OAGB data from major registries. Appreciatively, the short- and long-term risks and outcomes of the RYGB cannot be kept secret, providing a superlative tool for advancing both the surgery itself and the bariatric field. Learning from the advantages and liabilities is a must. Finding an equilibrium between safety and efficacy is a must. Reproducibility is a must. Reimbursement is a must. Transparency is a must. When RYGB satisfies all the above checkpoints and MGB/OAGB satisfies none, is there really a debate? One should not confuse enthusiasm and lobbying with realism and data.

References

1. Buchwald H, Buchwald JN. Evolution of operative procedures for the management of morbid obesity 1950-2000. Obes Surg. 2002;12(5):705-717.
2. McCarthy HB, Rucker RD Jr, Chan EK, et al. Gastritis after gastric bypass surgery. Surgery. 1985;98(1):68-71.
3. Tanigawa N, Nomura E, Lee SW, et al. Current state of gastric stump carcinoma in Japan: based on the results of a nationwide survey. World J Surg. 2010;34(7):1540-1547.
4. Haddad A, Bashir A, Fobi M, et al. The IFSO worldwide one anastomosis gastric bypass survey: techniques and outcomes? Obes Surg. 2021;31(4):1411-1421.
5. Robert M, Espalieu P, Pelascini E, et al. Efficacy and safety of one anastomosis gastric bypass versus Roux-en-Y gastric bypass for obesity (YOMEGA): a multicentre, randomised, open-label, non-inferiority trial. Lancet. 2019;393(10178):1299-1309.
6. Bhandari M, Nautiyal HK, Kosta S, et al. Comparison of one-anastomosis gastric bypass and Roux-en-Y gastric bypass for treatment of obesity: a 5-year study. Surg Obes Relat Dis. 2019;15(12):2038-2044.

The One-Anastomosis Gastric Bypass Is the Superior Operation

In 2001, an article was published in Obesity Surgery, reporting a new operation in a series of 1,274 cases using a single-anastomosis version of a gastric bypass.¹ This simplified version of a Roux-en-Y gastric bypass avoided creation of a small gastric pouch and eliminated the second distal anastomosis required in the RYGB. This publication described what is now known as the one-anastomosis gastric bypass (OAGB), an operation that has become the most effective and widely performed operation for the treatment of obesity around the world.

Despite an overwhelming body of evidence and hundreds of publications proving that OAGB outperforms the RYGB,^2,3 OAGB remains an underused operation in the United States. What has become the safest, most effective, reliable, consistent and standardized operation for the treatment of obesity in the world is sadly of limited access in the United States.

In the most recent randomized controlled trials of OAGB versus RYGB, the most important benefits of OAGB over RYGB were better glycemic control and a higher type 2 diabetes remission rate. Improved HbA_1c [hemoglobin A_1c] and a spectacular five-year resolution rate of type 2 diabetes of 70.5% for OAGB, versus a rate of 39.4% with RYGB,⁴ can no longer be ignored. The OAGB should be recognized and used in the United States as the better operation for both primary and revisional bariatric operations in the treatment of morbid obesity and its significant comorbid conditions.

Over the past 25 years of bariatric surgery, the issue of standardization of procedures has been an important but elusive clinical goal. In the last 20 years, the OAGB has evolved into a standardized operation using anatomic landmarks and a technical description that virtually all OAGB surgeons use to create a consistent and technically identical operation. The only differences between the two accepted OAGB techniques remain whether a side-to-side technique of gastrojejunostomy (as described by Carbajo) or the end-to-side anastomosis (as described by Rutledge) should be used. Both techniques describe creating a gastric pouch beginning 1 to 2 cm below the crow’s foot and extending vertically toward the angle of His. A simple loop gastrojejunostomy between the jejunum and distal gastric pouch beginning 150 to 200 cm beyond the ligament of Treitz completes the operation.

The OAGB is a simple, reproducible and standardized procedure that is employed by the majority of surgeons performing bariatric surgery around the world. In contrast, the RYGB has become the most nonstandardized, ever-changing bariatric operation used in the United States. Since its wide adoption as a laparoscopic bariatric operation in 1999-2000, there are now multiple variations of the RYGB performed. No standardization regarding pouch size, alimentary limb length, BP limb length or even closure of mesenteric defects exists. The BP limb lengths are now a random assortment of different lengths⁵—some as short as 20 cm to those reaching 100 to 200 cm. Alimentary limb lengths can vary from as short as 50 cm to more than 100 cm. With respect to length and width, the creation of the gastric pouch has no standardization. Parietal cell mass is therefore largely preserved, affecting rates of marginal ulcers and GERD following RYGB.

The RYGB resembles a sort of “shape shifter” from a Harry Potter novel, incorporating many significant changes in technique and limb length that did not occur from any evidence-based outcomes. The operation simply changed. As a result, there are very different forms of what is universally called the RYGB being performed. The lack of standardization of the RYGB between practices raises questions about the validity of published data since the variations between techniques are not addressed.

In the most recent study describing optimal limb length and OAGB, a BP limb length of 150 to 180 cm was optimal, safe and effective in terms of excess weight loss and comorbidity improvement. Malnutrition effects were low, even in patients with a body mass index greater than 50 kg/m². The OAGB is now a reproducible and defined operation that has consistent results and is easy to perform.

Unfortunately, to this day, RYGB remains nonstandardized and variable. The issue of how long to make the BP limb remains unresolved and fluctuates between practices. The most recent study of long versus short BP limb compared a 50-cm with a 200-cm BP limb.⁵ The RYGB group with the 200-cm BP limb has a BP design that is now identical to the OAGB. Weight loss and HbA_1c levels were better at 12 months with the longer limb. Better outcomes with the 200-cm BP limb in RYGB is a recognition that the longer BP limb lengths in OAGB have a preferred metabolic and clinical outcome. RYGB may finally incorporate the anatomic design of a long BP limb used for years with the OAGB.

Perhaps now, after more than 20 years of discussion and animosity between the RYGB and OABG, we are seeing an evolution of the RYGB into what has always been the standardized design of the OAGB.

References

1. Rutledge R. The mini-gastric bypass: experience with the first 1,274 cases. Obes Surg. 2001;11(3):276-280.
2. Higa K, Brown W, Himpens J. Editorial: Single anastomosis procedures, IFSO position statement. Obes Surg. 2018;28(5):1186-1187.
3. De Luca M, Tie T, Ooi G, et al. Mini gastric bypass–one anastomosis gastric bypass (MGB-OAGB)—IFSO position statement. Obes Surg. 2018;28(5):1188-1206.
4. Zerrweck C, Herrera A, Sepulveda E, et al. Long versus short biliopancreatic limb in Roux-en-Y gastric bypass: short-term results of a randomized clinical trial. Surg Obes Relat Dis. 2021;S1550-7289(21)00186-6.
5. Lee, W-J, Almalki O, Ser K-H, et al. Randomized controlled trial of one anastomosis gastric bypass versus Roux-en-Y gastric bypass for obesity: comparison of the YOMEGA and Taiwan studies. Obes Surg. 2019;29(9);3047-3053.

Dr. Ghanem’s Rebuttal to Dr. Billy

While my goal was to elaborate further on some of the distinguishing aspects between the two operations, the copious erroneous claims raised by my frenemy urged me to kick off this rebuttal where I concluded my initial piece: enthusiasm and lobbying versus realism and data. Thus, a fact checker.

Sleeve gastrectomy (and not MGB/OAGB) is the safest and most commonly performed procedure around the world. Although MGB/OAGB was described more than 20 years ago, it still comprises 4.1% of the total bariatric surgeries completed worldwide (vs. 31.2% for RYGB).¹ Additionally, biliopancreatic diversion with duodenal switch (and not MGB/OAGB) continues to be the most effective metabolic procedure for weight loss and diabetes resolution.

Few publications (and not hundreds) showed more weight loss and diabetes resolution in MGB/OAGB, but the Level I evidence that takes both efficacy and safety into consideration does not support this misleading “superiority” concept. In fact, YOMEGA was labeled by the MGB/OAGB pioneers as a noninferiority trial due to its modest safety outcomes. The widespread premise of lack of internal hernias in MGB/OAGB was rejected by a recent publication elucidating an incidence of 2.8% after MGB/OAGB.² The reproducibility claim is denied by the MGB/OAGB gurus , who find a technical defective surgical design in every study that reports reflux after MGB/OAGB.³

The most standardized operation declaration is refuted by Dr. Billy himself as he mentioned two models or modifications (although there exists more) of MGB/OAGB, as well as him promoting an optimal 150- to 180-cm BP length—a newborn hypothesis that only became popular after the mortifying safety data from YOMEGA. Others preach for tailoring the BP limb length according to BMI,⁴ so where is the standardization? While Dr. Billy advertises this as a disadvantage, the gorgeousness of RYGB is that standardization (including limb lengths) is not essential for exceptional outcomes.⁵

When a new procedure is promoted, surgeons expect this “novel” design to seal a practice gap. Which gap is MGB/OAGB trying to fill? Efficacy being promoted as the sole determinant in choosing the optimal bariatric operation takes our field back to the jejuno-ileal bypass era. The RYGB embraces efficacy, safety, comorbidity resolution, teachability and reproducibility. Until science proves otherwise, the RYGB is king and sits on the iron throne.

References

1. International Federation for the Surgery of Obesity and Metabolic Disorders. www.ifso.com/ pdf/ 5th-ifso-global-registry-report-september-2019.pdf
2. Petrucciani N, Martini F, Kassir R, et al. Internal hernia after one anastomosis gastric bypass (OAGB): lessons learned from a retrospective series of 3368 consecutive patients undergoing OAGB with a biliopancreatic limb of 150 cm. Obes Surg. 2021;31(6):2537-2544.
3. Musella M, Vitiello A. The YOMEGA non-inferiority trial. Lancet. 2019;394(10207):1412.
4. Lee WJ, Wang W, Lee YC, et al. Laparoscopic mini-gastric bypass: experience with tailored bypass limb according to body weight. Obes Surg. 2008;18(3):294-299.
5. Ahmed B, King WC, Gourash W, et al. Proximal Roux-en-Y gastric bypass: addressing the myth of limb length. Surgery. 2019;166(4):445-455.

Dr. Billy’s Rebuttal to Dr. Ghanem

“Realism and data” versus “enthusiasm and lobbying.” The MGB remains the world’s most overscrutinized bariatric surgery operation. IFSO reviewed more than 16,000 published cases and issued an endorsement for MGB/OAGB. That endorsement included two former ASMBS presidents. Data review must never be selective. The YOMEGA data set included better excess weight loss with OAGB at two years.¹ Mean excess BMI lost favored OAGB. Two-year mean percentage total body weight loss was superior for OAGB. Mean operative time was significantly shorter with OAGB. The YOMEGA data set included an eye-opening mean hospital stay of five days in both groups! Five days! American practices are reporting mean lengths of stay that are far less.

Cancer concerns? Tens of thousands of published MGB cases and no cancer papers? No associated cancer trend with MGB has been published. Presenting a position that there is a cancer concern without providing a single study linking a connection between MGB and cancer is the very definition of lobbying.

Is YOMEGA with its five-day mean length of stay really an important randomized trial? Why was the 2019 randomized controlled trial by Lee comparing the Taiwan trial and YOMEGA ignored? When including Lee’s data, OAGB remained technically easier, had better glycemic control and patients had less abdominal pain than with RYGB.² Revisional surgery of OAGB patients in Taiwan? Zero. Malnutrition? Less in Taiwan than in YOMEGA. Surgical complication rate for OAGB? Again, lower in Taiwan. Bile reflux? The incidence of bile reflux was low in OAGB and did not influence the quality of life compared with RYGB.

Funny thing about data: It reveals the truth when you consider all of it.

References

1. Lee WJ, Almalki O, Ser KH, et al. Randomized controlled trial of one anastomosis gastric bypass versus Roux-en-Y gastric bypass for obesity: comparison of the YOMEGA and Taiwan studies. Obes Surg. 2019;29(9);3047-3053.
2. Gormsen J, Burcharth J, Gogenur I, et al. Prevalence and risk factors for chronic abdominal pain after Roux-en-Y gastric bypass surgery: a cohort study. Ann Surg. 2021;273(2):306-314.

To comment on this Great Debate or to suggest future topics, contact the editor at khorty@mcmahonmed.com.