INS and cancer: Large real-world analyses suggest an association between GLP-1RA exposure and lower incidence of several obesity-associated cancers, including endometrial cancer (GLP-1RA vs. insulin, HR 0.74; 95% CI 0.60–0.91), while showing no overall advantage vs. metformin—signals that remain observational and potentially affected by allocation/immortal-time bias and limited site-specific power [69,70].