The Most Important Message

Start Here: The Short Answer

Bowen disease is highly treatable. “In situ” means the abnormal cells have not crossed into the deeper skin. It is not the same as invasive squamous cell carcinoma, and a diagnosis does not mean that cancer has spread through the body.

Bowen disease—also called squamous cell carcinoma in situ, SCC in situ, intraepidermal carcinoma, or stage 0 squamous cell carcinoma—usually appears as a slowly enlarging, persistent, red or brown scaly patch. It can resemble eczema, psoriasis, a fungal rash, an actinic keratosis, or another skin cancer. A biopsy is used to confirm the diagnosis and to look for invasion.

While Bowen disease stays within the epidermis, it has no access to deeper blood vessels or lymphatic channels and does not metastasize. The reason to treat it is to clear the abnormal cells before they have an opportunity to cross the boundary into deeper skin. If invasion develops, the condition is managed as invasive squamous cell carcinoma, which has a different risk profile and treatment plan.

How to Use This Guide

Sections 1–7 explain the diagnosis and risk. Sections 8–13 compare treatments and preparation. Sections 14–18 cover healing, results, follow-up, special situations, self-checking, and prevention. The final pages provide questions, a personal treatment plan, warning signs, and Canadian sources.

Not a Personal Treatment Plan

This guide supports discussion with your healthcare professional. It cannot determine whether your lesion is still in situ, which treatment is best, or how urgently you need treatment.