Suggest Treatment For Dry And Itchy Skin All Over Body

I itch all over my body. I sometimes scratch my legs until they bleed. I take Benedryl at night in order to sleep. I've seen several doctors who said it was dry skin however nothing helps. I have creams that I use. Last year I had Kidney cancern and my left kidney was removed. I've heard itching can be a symptom of cancer. Can you help me.