Patients with type 2 diabetes are at higher risk of several cancers. However, patients taking the diabetes drug metformin (Glucophage) have a lower risk of developing some kinds of cancer. Now, a review of several studies suggests that Glucophage also improves survival rates for patients who already have cancer. Patients with cancer and diabetes who took Glucophage had a lower risk of death overall, and of dying of cancer specifically, compared to patients receiving other diabetes medications. It is not certain that Glucophage indeed caused the survival benefit. Separate, independent factors could make patients both more likely to be prescribed Glucophage and to have better survival. However, because there is at least a strong possibility of a benefit, the review authors recommend Glucophage as the drug of choice for diabetes patients with cancer.