question: Hello, my son had a stage 3 brain tumor on the left side 8 years ago....removed successfully except for losses in his abilities,however, he had surgery on his lip a few months ago and now this lump ( size of a tennis ball) under his R arm they are calling possible Melanoma. They are ( considering) taking it out........he is so worried that they might even take his arm off. His wife tries to console him ( and herself) that it is just the lump. His appointment is for next Thursday. Please help me understand......