I am a 77 year old female suffering from sore nipples. Cause? Cure? Thanks

Several causes. Might be hormonal more than anything else. For something bad ( cancer) to happen and affect both nipples at the same time would be extremely unlikely. But an elevated prolactin can do this ( many medicines can do this, ie. Meclopropamide), and a low thyroid will also elevate prolactin levels. Finally, if you are using a new detergent for your bra, this might causes some reaction.