actinic keratosis
"I had extensive AKs for the past10  years on my forehead, scalp, temples, face and hands.  Regular liquid nitrogen treatments removed those which were visible.  They would return and other unseen AKs would appear.  I wanted more effective treatment so I did almost 3 weeks of heavy applications of fluororacil 5%, 2x/day.  The burning, blistering, cracking, stinging and swelling is most impressive.  After nearly 3 weeks, my derm said I was done and it would take 2 weeks to improve alot, and 4 to be all better.  He was right.  My skin is great now, looks good and no AKs!  It's miserable getting there but less cancer risk - why wouldn't you do it?"