That’s a difficult call. These are incidental stone so they can or cannot cause problems. Does yr father have other co morbid conditions like hypertension , Diabetes etc. decision to operate or not have to merited on many other factors. One school of thought would be if no CO morbid conditions then stitch in time saves nine. But as I said need to see how medically fit yr father is.

Today he can get operated. But if this stone starts complications at the age of 70 or ahead then he may not be fit for surgery. It is a routine surgery and relatively very safe. Also stones cannot be treated with any meds because new stones keep on forming, old ones keep on dissolving or growing.