Topical therapy treats basal and squamous cell carcinoma using creams and ointments that you apply directly to your skin in the affected area. Topical therapy kills cancer cells that have not spread to your lymph nodes (via Mercy Health).
NSW Cancer Council offers two types of topical therapy for skin cancer. Imiquimod is an immunotherapy cream designed to make your immune system kill cancer cells. Imiquimod works for sunspots and BCC. You apply the cream every night, five days a week, for six weeks.
The other topical treatment offered by the Cancer Council NSW is a chemotherapy drug called 5-fluorouracil (5-FU), which is also distributed as a cream. Like Imiquimod, 5-FU treats sunspots. Doctors also prescribe 5-FU for CTS, which works best on the face and scalp. Health professionals recommend using 5-FU twice a day for two to three weeks.
The Skin Cancer Foundation puts the success rate of both types of topical treatments at 80-90% effectiveness. This rate is due, in part, to the fact that with topical treatments, no tissue is removed for microscopic examination. Therefore, there is no way of knowing if the cancer is completely gone once you have finished your treatment.
Many patients seek topical treatment because it’s convenient and scarring is minimal (per Mercy Health). However, blistering, scaling, and crusting often cause many patients to stop treatment prematurely (via The Journal of Clinical and Aesthetic Dermatology). According to the Cancer Council NSW, side effects diminish a few weeks after treatment ends.