Yesterday, we took a look at a small case-control study demonstrating a link between metformin use and better survival in ovarian cancer .  In the final paragraph, I pointed another case-control study published in the British Medical Journal that served as the basis for this interest.  Just so we're clear, the study was published early online in April 2005 and in print in June 2005.  The authors compared 983 patients avg 73yo who'd been diagnosed to 1846 controls w/o cancer, all of whom were diabetic (avg duration 8.5yrs).  They then compared those who'd taken metformin to those who hadn't.  In the end, the authors concluded that the longer the duration on metformin and the greater the total dose of metformin, the lower the risk of developing diabetes.