Effect of bariatric surgery on oncologic outcomes: a systematic review and meta-analysis
- 894 Downloads
Obesity is a major public health issue and is associated with increased risk of several cancers, currently a leading cause of mortality. Obese patients undergoing bariatric surgery may allow for evaluation of the effect of intentional excess weight loss on subsequent risk of cancer. We aimed to evaluate cancer risk, incidence, and mortality after bariatric surgery.
A comprehensive literature search was conducted using PubMed/MEDLINE and Embase with literature published from the inception of both databases to January 2012. Inclusion criteria incorporated all human studies examining oncologic outcomes after bariatric surgery. Two authors independently reviewed selected studies and relevant articles from their bibliographies for data extraction, quality appraisal, and meta-analysis.
Six observational studies (n = 51,740) comparing relative risk (RR) of cancer in obese patients undergoing bariatric surgery versus obese control subjects were analyzed. Overall, the RR of cancer in obese patients after undergoing bariatric surgery was 0.55 [95 % confidence interval (CI) 0.41–0.73, p < 0.0001, I 2 = 83 %]. The effect of bariatric surgery on cancer risk was modified by gender (p = 0.021). The pooled RR in women was 0.68 (95 % CI 0.60–0.77, p < 0.0001, I 2 < 0.1 %) and in men was 0.99 (95 % CI 0.74–1.32, p = 0.937, I 2 < 0.1 %).
Bariatric surgery reduces cancer risk and mortality in formerly obese patients. When stratifying the meta-analysis by gender, the effect of bariatric surgery on oncologic outcomes is protective in women but not in men.
KeywordsBariatric surgery Cancer Oncology Meta-analysis
We thank Carol Mita, reference librarian at the Countway Library of Medicine, Harvard University, Boston, MA, USA
Drs. Tee, Warnock, Hu, and Chavarro and Ms. Cao have no conflicts of interest or financial ties to disclose.
Supported in part by grants 5P30DK46200-18 and U54CA155626-01 from the National Institutes of Health.
- 7.McTiernan A (2005) Obesity and cancer: the risks, science, and potential management strategies. Oncology (Williston Park) 19(7):871–881Google Scholar
- 11.Sjöström L, Lindroos AK, Peltonen M, Torgerson J, Bouchard C, Carlsson B, Dahlgren S, Larsson B, Narbro K, Sjöström CD, Sullivan M, Wedel H, Swedish Obese Subjects Study Scientific Group (2004) Lifestyle, diabetes, and cardiovascular risk factors 10 years after bariatric surgery. N Engl J Med 351(26):2683–2689PubMedCrossRefGoogle Scholar
- 12.Sjöström L, Narbro K, Sjöström CD, Karason K, Larsson B, Wedel H, Lystig T, Sullivan M, Bouchard C, Carlsson B, Bengtsson C, Dahlgren S, Gummesson A, Jacobson P, Karlsson J, Lindroos AK, Lönroth H, Näslund I, Olbers T, Stenlöf K, Torgerson J, Agren G, Carlsson LM, Swedish Obese Subjects Study (2007) Effects of bariatric surgery on mortality in Swedish obese subjects. N Engl J Med 357(8):741–752PubMedCrossRefGoogle Scholar
- 13.Blackburn GL, Hutter MM, Harvey AM, Apovian CM, Boulton HR, Cummings S, Fallon JA, Greenberg I, Jiser ME, Jones DB, Jones SB, Kaplan LM, Kelly JJ, Kruger RS Jr, Lautz DB, Lenders CM, Lonigro R, Luce H, McNamara A, Mulligan AT, Paasche-Orlow MK, Perna FM, Pratt JS, Riley SM Jr, Robinson MK, Romanelli JR, Saltzman E, Schumann R, Shikora SA, Snow RL, Sogg S, Sullivan MA, Tarnoff M, Thompson CC, Wee CC, Ridley N, Auerbach J, Hu FB, Kirle L, Buckley RB, Annas CL (2009) Expert panel on weight loss surgery: executive report update. Obesity (Silver Spring) 17(5):842–846CrossRefGoogle Scholar
- 19.Stroup DF, Berlin JA, Morton SC, Olkin I, Williamson GD, Rennie D, Moher D, Becker BJ, Sipe TA, Thacker SB (2000) Meta-analysis of observational studies in epidemiology: a proposal for reporting. Meta-analysis of Observational Studies in Epidemiology (MOOSE) group. JAMA 283(15):2008–2012PubMedCrossRefGoogle Scholar
- 21.Egger M, Davey Smith G, Altman DG (eds) (2001) Systematic reviews in health care: meta-analysis in context, 2nd edn. BMJ Books, LondonGoogle Scholar
- 23.Sjöström L, Gummesson A, Sjöström CD, Narbro K, Peltonen M, Wedel H, Bengtsson C, Bouchard C, Carlsson B, Dahlgren S, Jacobson P, Karason K, Karlsson J, Larsson B, Lindroos AK, Lönroth H, Näslund I, Olbers T, Stenlöf K, Torgerson J, Carlsson LM, Swedish Obese Subjects Study (2009) Effects of bariatric surgery on cancer incidence in obese patients in Sweden (Swedish Obese Subjects Study): a prospective, controlled intervention trial. Lancet Oncol 10(7):653–662PubMedCrossRefGoogle Scholar
- 31.O’Brien PE, Dixon JB, Laurie C, Skinner S, Proietto J, McNeil J, Strauss B, Marks S, Schachter L, Chapman L, Anderson M (2006) Treatment of mild to moderate obesity with laparoscopic adjustable gastric banding or an intensive medical program: a randomized trial. Ann Intern Med 144(9):625–633PubMedCrossRefGoogle Scholar
- 32.Imayama I, Ulrich CM, Alfano CM, Wang C, Xiao L, Wener MH, Campbell KL, Duggan C, Foster-Schubert KE, Kong A, Mason CE, Wang CY, Blackburn GL, Bain CE, Thompson HJ, McTiernan A (2012) Effects of a caloric restriction weight loss diet and exercise on inflammatory biomarkers in overweight/obese postmenopausal women: a randomized controlled trial. Cancer Res 72(9):2314–2326PubMedCrossRefGoogle Scholar