I have had melanoma and Bowen’s Disease, and read conflicting reports of the benefit or risk of taking Vitamin A supplements and/or topical creams containing tretinoin. The latter is said to heal wounds and increase collagen production and angiogenesis, but won’t that encourage skin cancers? A rodent study showed Vitamin A(or it’s carrier) increased photomutagenesis. Some reports show retinoic acid thinning and irritating skin. But the use of retinyls in some sunscreens makes it confusing!