Benign, premalignant, and malignant lesions encountered in bariatric surgery.

Background: Obesity is associated with several comorbidities like diabetes, hypertension, hyperlipidemia, and obstructive sleep apnea. It is also well established that obese patients have an increased risk of several types of cancer like kidney, pancreas, endometrial, breast, and others. The bariatric surgeon needs to be aware of the problem of benign tumors and cancer in obese patients as well as the optimal management of these conditions that may be present at the time of evaluation for bariatric surgery, during the surgical procedure, and in the postoperative period.

Database: A PubMed search for the words "cancer" and "bariatric surgery" and subsequent review of the abstracts identified 40 articles concerning cancerous, benign, and premalignant conditions in bariatric surgery patients. Data were then extracted from full-text articles.

Conclusion: Bariatric surgery decreases cancer risk especially in women. RYGB can be an effective treatment for Barrett's esophagus. Patients having esophageal cancer should not undergo bariatric surgery, while those who develop the same postoperatively are usually managed by a combined abdominal and thoracic approach (Ivor Lewis technique). Gastric cancer of the remnant stomach is usually managed by a remnant gastrectomy. A remnant gastrectomy during RYGB would be necessary in conditions that require endoscopic surveillance of the stomach like gastric polyps, intestinal metaplasia, and carcinoid tumors. Sleeve gastrectomy is an excellent option in a patient with GIST or a carcinoid who needs a bariatric operation. Preoperative endoscopy usually does not detect malignant conditions. Postoperative evaluation of the bypassed stomach is possible using various percutaneous and novel endoscopic techniques.