Bariatric surgery linked to negative outcomes in chronic myeloid leukemia management

A new study revealed that bariatric surgery has been linked to lesser ideal and negative outcomes for patients with chronic myeloid leukemia as it alters the body's way of absorbing drugs. The study results were published in the journal Cancer. 

Obesity has become a major epidemic in recent times triggering many health problems. Bariatric surgery is one of the best weight loss interventions for obesity. But it can also make oral drugs less bioavailable. Oral targeted medications like tyrosine kinase inhibitors are the cornerstone treatment for chronic myeloid leukemia (CML). Bariatric surgery affects the availability of such drugs and its effect on the course of CML is uncertain. 

Hence researchers conducted a retrospective analysis to evaluate the impact of bariatric surgery on CML outcomes. Nearly 652 patients with CML were identified. Among them, there were 22 patients with prior bariatric surgery. They were compared to a matched cohort of 44 patients without prior bariatric surgery. 

Key findings: 

• When compared to the control group (91%), the bariatric surgery group showed a lower rate of early molecular response (68%; p = .05). 
• Bariatric group took longer median times to achieve complete cytogenetic (6 vs. 3 months; p = .001) or major molecular responses (12 vs. 6 months; p = .001) compared to the control group.
• Bariatric surgery was associated with inferior event-free survival (5-year, 60% vs. 77%; p = .004) and failure-free survival (5-year, 32% vs. 63%; p < .0001).
• Multivariate analysis showed bariatric surgery as the only independent predictor for the risk of treatment failure (hazard ratio, 9.40; 95%; p = .0004) or event-free survival (hazard ratio, 4.24; p = .008).  

Thus, Bariatric surgery is linked to less-than-ideal outcomes that call for customized treatment plans. Hence the authors suggested that the dosage of the drugs be altered once a patient does not respond to the treatment or switch to other TKIs as measuring the blood levels of TKIs is not easily available. 

Further reading: Haddad FG, Kantarjian HM, Bidikian A, et al. Association between bariatric surgery and outcomes in chronic myeloid leukemia [published online ahead of print, 2023 Mar 7]. Cancer. 2023;10.1002/cncr.34725. doi: 10.1002/cncr.34725