What should you know about topical chemo for skin cancer?

Topical chemotherapy acts on cells in the treated skin area rather than being given through a vein. A clinician chooses it only when the lesion's type, extent and depth make a surface treatment appropriate. It may be used for some early or superficial skin changes, but it cannot reach every deeper or invasive cancer. A biopsy or examination may be needed before treatment so the diagnosis is clear.

During the course, treated skin can become red, sore, swollen, crusted or irritated as abnormal cells respond. The appearance may worsen before it settles. Reactions vary with the medicine, treatment schedule, body site and skin sensitivity. Do not assume that a quiet-looking area means treatment is complete; follow-up confirms the response.

Use the prescribed amount and schedule, applying it only to the instructed area. Wash hands before and after application, avoid eyes and broken skin unless specifically directed, and keep the product away from children and pets. Do not add dressings, moisturisers or other skin products without checking first. Protect the area from friction and follow instructions about sunlight. Keep every review appointment so the clinician can assess healing and decide whether further treatment is needed.

Call the treating team if pain prevents sleep or normal activity, redness spreads beyond the treated area, drainage develops, fever occurs, or swelling affects an eye, mouth or airway. Seek urgent help for breathing difficulty, facial swelling or a severe allergic reaction. Pause or change treatment only after receiving medical advice, unless emergency services instruct you otherwise.

What exact diagnosis is being treated, and why is a cream suitable? How should I apply it and for how long? Which reaction is expected, and what should prompt a call? Can I use other skin products? How will you confirm that the lesion has cleared, and what happens if it has not?