How effective is topical 5-fluorouracil for Bowen's disease?

Bowen's disease, also called squamous cell carcinoma in situ, involves abnormal cells confined to the outer skin layer. Topical 5-fluorouracil can act on these abnormal cells and may be considered for suitable superficial lesions. The treated patch often becomes inflamed, sore, scaly or crusted before healing.

This approach is not suitable for every lesion. Location, size, thickness, borders, immune health and whether the diagnosis has been confirmed all affect the decision. A deeper, thickened, ulcerated or tender area may need a procedure that removes tissue or allows it to be examined.

Use the prescribed preparation exactly as directed and keep every follow-up appointment. Do not cover, extend or restart treatment without advice. Protect the area from sunlight, avoid picking the reaction and ask which bland cleanser or moisturiser can be used while the skin repairs.

Before starting, clarify how the diagnosis was made, what response is expected and how the clinician will confirm clearance. Tell the clinician about immune-suppressing medicines, pregnancy or plans for pregnancy, allergies and previous problems with wound healing.

Contact the treating clinician for severe pain, spreading redness, pus, fever, extensive blistering or a reaction that affects untreated skin. Seek prompt assessment for a persistent ulcer, bleeding, new lump, increasing thickness or any lesion that remains after the prescribed course.

Ask whether the lesion is appropriate for cream, how clearance will be checked, what alternatives exist, which reaction is expected, and when a biopsy or removal would be considered.