The Lancet has published two Commissions in 2024 addressing the commonest cancers among men and women: prostate cancer (led by Nicholas James) and breast cancer (led by Charlotte Coles). As we were preparing these Commissions for publication, we considered writing an editorial linking the two cancers. But we hesitated. Surely these conditions are distinguished by their differences, not their similarities. Breast cancer is preventable. No such possibilities exist for prostate cancer. As our Commission on Prostate Cancer concluded: “The projected rise in prostate cancer cases cannot be prevented by lifestyle changes or public health interventions.” Yet, observing their launches and listening to the debates they provoked suggests that these cancers have more in common than might be appreciated—synergies that have important implications for accelerating cancer prevention and control.