Fortunately pre-cancerous growths on the face of older peole is quite common and if pre-caucerous are usually temoved with liguid nitrogen. If he id decide to biopsy the probable diagnosis will be an actinic keratosis. Hope for that it's very treatable. The other is a basal cell carcinoma and that is removed with Mohn surgey with a 97-99% cure rate. Others are a possibility but a trained dermatologist wouls easily identify these are cancerous not pre-cancerous. Hope this eases your mind.