Topical treatments for skin cancer

Skin cancer is a broad term used to describe a number of different malignant indications of the skin. Skin cancers mostly comprise of the keratinocyte cancers [Basal Cell Carcinoma (BCC) and cutaneous Squamous Cell Carcinoma (SCC)], and melanoma. Surgical excision of these malignancies has been the preferred treatment of patients for decades. However, the decision to perform surgery can be affected by various considerations, including co-morbidities of the patient, the anatomical site of the lesion and potential intolerance for repeated excisions. Topical treatment of skin cancer may therefore be more appropriate in certain instances. Topical treatment potentially allows for higher drug levels at the tumor site, and may result in less overall toxicity than systemic agents. This review will specifically address the current agents used in topical treatment of skin cancers, and introduce emerging treatments from the natural product field that may also find utility in these indications.