Related Experiment Video
Updated: Jun 20, 2026
Single-Port Robotic-assisted Transaxillary Breast-conserving Surgery: A Prospective, Single-arm, Non-randomized Phase IIa Clinical Trial
Published on: August 19, 2025
Effect of bariatric surgery timing on breast cancer incidence: Real-world evidence from TriNetX
Kian-Hwee Chong1, Yao-Jen Chang1, Joshua Wang2
1Department of Surgery, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, 23142, Taiwan; School of Medicine, Buddhist Tzu Chi University, Hualien, 97004, Taiwan.
Purpose:
Obesity increases the risk of breast cancer (BC), and bariatric surgery may lower overall cancer risk. However, the impact of sleeve gastrectomy (SG) timing on cancer outcomes remains unclear.
Patients And Methods:
Using the TriNetX global health research network, we identified 4,439,072 women diagnosed with severe obesity (BMI >35 kg/m2) between 2010 and 2019. Patients were grouped into SG and nonsurgical controls, with SG patients further stratified by surgery timing: early (≤6 months), intermediate (6-12 months), and delayed (1-3 years) post-diagnosis. Propensity score matching adjusted for demographics, comorbidities, BMI, and HbA1c. Outcomes included 5-year incidences of mortality, cancer, and metastasis.
Results:
SG was associated with lower 5-year all-cause mortality across all timing groups compared to the control group. Early SG was significantly associated with a reduced 5-year incidence of BC (risk ratio [RR]: 0.799; 95% CI: 0.647 to 0.987; P = .037), gynecologic cancer (RR: 0.490; 95% CI: 0.378 to 0.635; P < .001), and metastasis (RR: 0.306; 95% CI: 0.230 to 0.408; P < .001). By contrast, delayed SG was associated with an increased risk of BC (RR: 1.404; 95% CI: 1.107 to 1.781; P = .005). Age-stratified analyses indicated that the association between SG timing and outcomes appeared more pronounced in patients aged ≥45 years.
Conclusions:
Our findings highlight the importance of timely bariatric surgery in optimizing both metabolic and oncologic outcomes, particularly in older women with obesity.
