Highlight
– Oral metformin treatment in patients with low-grade non-muscle-invasive bladder cancer showed limited antitumor efficacy, with only one complete and one partial response among 11 patients.
– Metformin was well-tolerated, with mild diarrhea being the most common adverse event.
– Urinary metformin concentrations exceeded systemic blood levels, but no significant changes were observed in immunohistochemical markers linked to metformin’s proposed mechanisms of action.
– The study concludes that oral metformin lacks conclusive evidence for antitumor benefit in NMIBC marker lesions.