Bowen's Disease on the Lower Leg When First-Line Treatment Has Not Cleared the Lesion
This protocol applies to squamous cell carcinoma in situ (Bowen's disease) presenting as a large lesion on the lower leg or another poorly healing site in an immunocompetent patient, where standard first-line treatment failed to achieve complete clearance.
Clinical Scenario
The patient has a large SCC in situ on the lower leg or a comparable poorly healing anatomical site. The patient is not immunosuppressed. Because of the site's tendency toward prolonged healing, the choice of treatment is critical — and some standard approaches carry a heightened risk of complications at this location.
Previous Treatment: Goal Not Met
A first-line option was used — one of: topical 5-fluorouracil, conventional photodynamic therapy, laser treatment (ablative or nonablative), curettage with cautery, or standard surgical excision. The treatment goal — complete clearance of the SCC in situ lesion within 6 months — was not achieved, or the first-line approach was contraindicated or produced an inadequate response. This escalation to a secondary option follows from that outcome.
Secondary Options: What the Protocol Covers
The protocol specifies secondary options suited to this scenario — including a topical immunomodulatory approach and a physical destructive method that requires specific technical adjustment for the lower leg to manage the risk of prolonged healing. The full protocol details which option applies, how it is adapted for this site, and the patient-factor considerations that guide the choice.
References
DOI: 10.1093/bjd/ljac042
- Consider topical 5-fluorouracil (5%) monotherapy in people with SCC in situ, for larger lesions on poorly healing sites (e.g. the lower legs of older patients) as a practical alternative to surgical treatments. Initiate a standard regimen of once- or twice-daily application for up to 4 weeks (see R9).
- For immunocompetent people with SCC in situ lesions located on the lower legs, use* treatments other than radiotherapy (apart from brachytherapy), due to prolonged healing time.
- Consider topical imiquimod in people with SCC in situ lesions located on the lower legs who are inappropriate for, have contraindication to or have inadequate response to topical 5-fluorouracil (5%), PDT, laser, curettage with cautery, or surgery (see R31).
- Consider cryotherapy on an individual basis, in people with SCC in situ with larger lesions, and those on the lower leg (see R15). Consider patient factors (age, location, skin health) and discuss the risk of prolonged healing and potential ulceration. The time of freezing may need to be shortened to avoid complications, but this is associated with a reduction in effectiveness.
View source ↗