MONDAY, April 2 (HealthDay News) — The diabetes drug metformin is safe in men with prostate cancer undergoing prostatectomy, and may improve prostate-specific antigen levels and curb tumor growth, according to a phase II study presented at the annual meeting of the American Association for Cancer Research, held from March 31 to April 4 in Chicago.
Noting that previous studies have suggested that metformin may be beneficial against prostate cancer, Anthony M. Joshua, M.B.B.S., Ph.D., from the Princess Margaret Hospital in Toronto, and colleagues analyzed data from 22 men with confirmed prostate cancer who were assigned 500 mg metformin up to three times a day before undergoing prostatectomy.
During a median of 41 days of treatment, the researchers observed no grade 3 adverse events, and all men underwent radical prostatectomy with no adverse effects attributed to metformin. There were significant improvements in serum insulin growth factor 1, fasting glucose, body mass index, and waist-to-hip ratio. Prostate-specific antigen levels tended to improve (P = 0.08). No associations were noted between any metabolic, morphometric, or cancer-related serum indices.
“Although these are preliminary results, metformin appeared to reduce the growth rate of prostate cancer in a proportion of men,” Joshua said in a statement. “This research builds on the hypothesis that metformin has a role in prostate cancer.”