Gynecomastia occurs during three common life periods: 1) during the postpartum period due to residual estrogen that travels across the placenta 2) during puberty, when hormones are all over the place 3) in "maturity"--which 60 would qualify, when testosterone levels drop and body fat levels increase. You should have your primary care doctor measure your hormone levels (testosterone, free testosterone, estradiol, prolactin) to see where things stand. You might benefit from hormone replacement. You may be able to limit the extent of development of your gynecomastia and avoid the need for surgery.
Good luck.