Guideline sources The following summarized guidelines for the evaluation and management of bowen disease are prepared by our editorial team based on guidelines from the British Association of Dermatologists (BAD 2023), the U.S. Preventive Services Task Force (USPSTF 2023; 2018), the American Society of Plastic Surgeons (ASPS 2021), the British Photodermatology Group (BPG/BAD 2019), and the European Dermatology Forum (EDF 2019). 1 2 3 4 5 6 Calculator TNM classification for nonmelan Guidelines https://web.pathway.md/diseases/recvKY60ZslrpQZeP 1/5 6/29/23, 3:21 AM Bowen disease Pathway 1. Screening and diagnosis Indications for screening: As per USPSTF 2023 guidelines, insufficient evidence to assess the balance of benefits and harms of visual skin examination by a clinician to screen for skin cancer in adolescents and adults. I As per USPSTF 2018 guidelines, insufficient evidence to assess the balance of benefits and harms of counseling adult persons about skin self-examination to prevent skin cancer. I 2. Diagnostic procedures Biopsy: consider performing a punch biopsy or diagnostic excision when clinical and dermoscopic features are not sufficient for diagnosis of SCC in situ. C Curettage: consider performing curettage for both diagnosis and treatment, depending on the clinical scenario and the operator's judgment. Ensure histology specimens include the deep margin if an assessment of a potentially invasive tumor is required. E 3. Medical management Conservative management: consider offering conservative measures, including moisturizers (preferably urea-based) and skin surveillance, in patients with poor health and multiple SCC in situ lesions, especially on the lower legs, where there is a greater risk of long-term ulceration after treatment. Perform a biopsy if SCC is suspected. E Topical 5-fluorouracil: offer topical 5-fluorouracil (5%) monotherapy, once daily or BID for 3-4 weeks, in patients with small lesions (such as < 2 cm) of SCC in situ in low-risk sites and in patients refusing or unable to undergo alternative treatments. A Show 5 more Topical imiquimod: Consider offering topical imiquimod (5%), thrice weekly for 4 weeks (although prolonged treatment for 12 weeks may be required), in patients with SCC in situ at low-risk sites, if there is no suitable alternative, recognizing that a reduction in efficacy may be observed in immunosuppressed patients. C Consider offering topical imiquimod in patients with SCC in situ lesions located on the lower legs being inappropriate for, having contraindications to, or exhibiting inadequate response to topical 5-fluorouracil (5%), photodynamic therapy, laser, curettage with cautery, or surgery. C Topical tazarotene: insufficient evidence to recommend tazarotene in patients with SCC in situ. I 4. Therapeutic procedures https://web.pathway.md/diseases/recvKY60ZslrpQZeP 2/5 6/29/23, 3:21 AM Bowen disease Pathway Photodynamic therapy: As per BAD 2023 guidelines, offer conventional, red-light photodynamic therapy as a treatment option in patients with SCC in situ, particularly for poorly healing or cosmetically sensitive skin sites, multiple lesions, and large lesions. A Show 2 more As per BPG 2019 guidelines, offer photodynamic therapy as a treatment option in patients with SCC in situ, particularly for poorly healing or cosmetically sensitive skin sites, multiple lesions, and large-area lesions. A Show 2 more As per EDF 2019 guidelines: Offer photodynamic therapy in patients with SCC in situ. A Do not offer photodynamic therapy in patients with invasive SCC. D Cryotherapy: offer cryotherapy as a first-line treatment option in patients with small (< 2 cm) SCC in situ lesions. A Show 3 more Curettage with cautery: perform curettage with cautery as first-line treatment in patients with small SCC in situ lesions, especially if a histological diagnosis is desirable. A Show 2 more Laser therapy: consider offering laser treatment (if available) in patients with SCC in situ when other treatments have failed or are unsuitable. Consider preferring ablative CO laser over nonablative Nd-YAG. C Radiotherapy: consider offering radiotherapy in immunocompetent patients with SCC in situ only where the lesion is recurrent or refractory to other treatments or where surgery is inappropriate or is associated with high morbidity. B Show 4 more 5. Surgical interventions Standard surgical excision: perform standard surgical excision in patients with SCC in situ if there is diagnostic uncertainty regarding an invasive disease. A Show 3 more Mohs micrographic surgery: Consider performing Mohs micrographic surgery in patients with SCC in situ when tissue conservation is important, such as around the eyes and the nail unit. C Consider offering active treatment with any suitable alternative (such as standard surgical excision, curettage with cautery, photodynamic therapy, 5-fluorouracil, imiquimod, laser, or cryotherapy) where Mohs micrographic surgery is not available or not appropriate. Discuss the risk of functional impairment, including that posed by recurrence and its subsequent treatment. E https://web.pathway.md/diseases/recvKY60ZslrpQZeP 3/5 6/29/23, 3:21 AM Bowen disease Pathway 6. Patient education General counseling: provide educational material or a patient information leaflet on SCC in situ and for any proposed treatment modality. E 7. Preventative measures Sun protection: Counsel persons with fair skin types aged 6 months to 24 years and parents of young children about minimizing exposure to UV radiation to reduce the risk of skin cancer. B Offer counseling selectively in adults > 24 years with fair skin types about minimizing exposure to UV radiation to reduce the risk of skin cancer, taking into consideration the presence of risk factors for skin cancer. B 8. Follow-up and surveillance Skin reconstruction after tumor resection (timing): consider performing reconstructive surgery in a delayed (asynchronous) fashion in adult patients after skin cancer resection. C Skin reconstruction after tumor resection (perioperative antibiotics): consider discussing the management of antibiotics with adult patients undergoing reconstruction after skin cancer resection when relevant. C Show 3 more Skin reconstruction after tumor resection (perioperative antithrombotics): consider discussing the management of anticlotting agents with adult patients undergoing reconstruction after skin cancer resection when relevant. C Show 2 more Skin reconstruction after tumor resection (perioperative analgesics): consider discussing the management of pain with adult patients undergoing reconstruction after skin cancer resection when relevant. C Show 2 more Skin reconstruction after tumor resection (follow-up): consider obtaining postoperative follow- up assessment in adult patients undergoing reconstruction after skin cancer resection. C Follow-up: consider discharging most patients with SCC in situ safely following the completion of treatment. Exercise clinical judgment when deciding to offer a follow-up appointment. E Show 2 more Clinical findings Patient demographics Symptoms https://web.pathway.md/diseases/recvKY60ZslrpQZeP 4/5 6/29/23, 3:21 AM Bowen disease Pathway Elderly Itching Past medical history Social history Actinic keratosis Exposure to excessive sun Basal cell carcinoma Exposure to chemotherapy HPV infection Human immunodeficiency virus infection Immunocompromising condition Integument exam Erythematous plaque Fitzpatrick skin type 1 Hyperkeratotic lesion Scaly skin patch Skin plaque References 1. T H Wong, C A Morton, N Collier et al. British Association of Dermatologists and British Photodermatology Group guidelines for topical photodynamic therapy 2018. Br J Dermatol. 2019 Apr;180 4 730 739. Open 2. Ashish Sharma, Andrew J Birnie, Cristina Bordea et al. British Association of Dermatologists guidelines for the management of people with cutaneous squamous cell carcinoma in situ Bowen disease) 2022. Br J Dermatol. 2023 Feb 10;188 2 186 194. Open 3. US Preventive Services Task Force, Grossman DC, Curry SJ et al. Behavioral Counseling to Prevent Skin Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2018 Mar 20;319 11 1134 1142. Open 4. Andrew Chen, John G Albertini, Jeremy S Bordeaux et al. Evidence-Based Clinical Practice Guideline: Reconstruction after Skin Cancer Resection. Plast Reconstr Surg. 2021 May 1;147 5 812e-829e. Open 5. C A Morton, R M Szeimies, N Basset-Seguin et al. European Dermatology Forum guidelines on topical photodynamic therapy 2019 Part 1 treatment delivery and established indications - actinic keratoses, Bowen's disease and basal cell carcinomas. J Eur Acad Dermatol Venereol. 2019 Dec;33 12 2225 2238. Open 6. US Preventive Services Task Force, Carol M Mangione, Michael J Barry et al. Screening for Skin Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2023 Apr 18;329 15 1290 1295. Open https://web.pathway.md/diseases/recvKY60ZslrpQZeP 5/5