Epidemiology

• The incidence in the UK is around 14 per 100,000 per year but a study of white people from Hawaii gave 10 times that figure, presumably because of exposure to strong sunlight.³ When associated with sunlight, the risk is much higher in white races.
• Some sources state that there is no difference in incidence between the sexes whilst others state that it is 3 times as common in women as in men.
• It tends to appear between the ages of 60 and 70.

Risk factors

• Exposure to sunlight (especially with fair skin) is a strong risk factor.
• Exposure to inorganic arsenic is less important than it was. Arsenic used to be found in Fowler's solution - used to treat psoriasis, in Gay's solution - used to treat asthma, in contaminated well water and in some pesticides.
• Other chemical carcinogens and trauma have been suggested but often no specific risk factor is found.
• Viral infection has been implicated, particularly human papillomavirus (usually HPV-16 but more rarely HPV-2).⁴
• More travel to exotic locations and a shrinking ozone layer make it an increasing problem.
• Suppression of the immune system appears to be a risk. Malignant and premalignant skin tumours are more common in patients who have received organ transplants. The risk is higher for heart recipients than for kidney recipients, perhaps as they are more strongly immunosuppressed.⁵ The literature also contains a number of reports of Bowen's disease, quite often extensive, in patients with HIV infection.⁶

Presentation

• It presents as a slowly growing erythematous patch or plaque. It is sharply demarcated, scaling or hyperkeratotic with a pink or red surface. There may be a small erosion or it may be crusted.
• Lesions are usually asymptomatic but can bleed. There may be a solitary lesion or multiple lesions. Two thirds are solitary.
• They are often found on sites exposed to sun and are most common on the head and neck, followed by the limbs; however, they may occur elsewhere - for example, as a disorder of the vulva. When it arises on the glans penis, it is referred to as Queyrat's erythroplasia. They vary in size from a few millimetres to a few centimetres. They are rarely pigmented. Diagnosis is often delayed, as it is asymptomatic and may appear similar to benign skin lesions.

Differential diagnosis

A characteristic feature is that it is well demarcated.

• Discoid eczema, other forms of eczema
• Psoriasis
• Lichen planus
• Seborrhoeic (solar) keratosis
• Superficial basal cell carcinoma
• Malignant melanoma
• Mammary Paget's disease

Investigations

A shave or punch biopsy is required for histological diagnosis. Where possible, include a hair follicle in the biopsy.

Management

Pharmacological

• Topical 5-fluorouracil cream may be used. It may be preceded by keratolytic therapy or cryotherapy. It can be used under occlusion or with iontophoresis, where an electrical current drives it into the tissues.⁷
• Imiquimod 5% cream appears to be an effective treatment for Bowen's disease on the lower limbs.⁸

Photodynamic therapy

Photodynamic therapy (PDT) may be valuable.^9,10 It is gaining wider acceptance and appears better for patients who developed the disease whilst immunosuppressed for transplantation.¹¹ It may be used for a number of other skin conditions too.¹² It can be rather painful and some form of topical anaesthesia is often required.¹³

Radiological

Superficial X-ray treatment may be best for those unsuitable for surgery, especially with multiple lesions.

Surgical

• Cautery, curettage and cryotherapy may be satisfactory but they give no histological diagnosis and may fail to reach all the affected tissue.
• Surgical excision is usually satisfactory for small lesions not on the face or the digits. Although the lesion looks clearly demarcated it may extend beyond the apparent boundary and so at least 5 mm of clearance should be allowed.
• Mohs micrographic surgery is excellent for larger lesions and those on the face or digits where it is important to be as sparing as possible with the extent of excision.¹⁴

Prognosis

This is excellent, especially with treatment. Untreated, 3 to 5% progress to invasive squamous cell carcinoma, but metastases are rare.

Document references

1. Arbesman H, Ransohoff DF; Is Bowen's disease a predictor for the development of internal malignancy? A methodological critique of the literature. JAMA. 1987 Jan 23-30;257(4):516-8. [abstract]
2. Jaeger AB, Gramkow A, Hjalgrim H, et al; Bowen disease and risk of subsequent malignant neoplasms: a population-based cohort study of 1147 patients. Arch Dermatol. 1999 Jul;135(7):790-3. [abstract]
3. Reizner GT, Chuang TY, Elpern DJ, et al; Bowen's disease (squamous cell carcinoma in situ) in Kauai, Hawaii. A population-based incidence report. J Am Acad Dermatol. 1994 Oct;31(4):596-600. [abstract]
4. Gormley RH, Kovarik CL; Dermatologic manifestations of HPV in HIV-infected individuals. Curr HIV/AIDS Rep. 2009 Aug;6(3):130-8. [abstract]
5. Euvrard S, Kanitakis J, Pouteil-Noble C, et al; Comparative epidemiologic study of premalignant and malignant epithelial cutaneous lesions developing after kidney and heart transplantation. J Am Acad Dermatol. 1995 Aug;33(2 Pt 1):222-9. [abstract]
6. Sharma R, Iyer M; Bowen's disease of the nipple in a young man with AIDS: a case report. Clin Breast Cancer. 2009 Feb;9(1):53-5. [abstract]
7. Welch ML, Grabski WJ, McCollough ML, et al; 5-fluorouracil iontophoretic therapy for Bowen's disease. J Am Acad Dermatol. 1997 Jun;36(6 Pt 1):956-8. [abstract]
8. Mackenzie-Wood A, Kossard S, de Launey J, et al; Imiquimod 5% cream in the treatment of Bowen's disease. J Am Acad Dermatol. 2001 Mar;44(3):462-70. [abstract]
9. Varma S, Wilson H, Kurwa HA, et al; Bowen's disease, solar keratoses and superficial basal cell carcinomas treated by photodynamic therapy using a large-field incoherent light source. Br J Dermatol. 2001 Mar;144(3):567-74. [abstract]
10. Attili SK, Ibbotson SH; How we treat Bowen's disease with topical photodynamic therapy in Dundee. Photodiagnosis Photodyn Ther. 2009 Mar;6(1):41-5. Epub 2009 May 5. [abstract]
11. Perrett CM, McGregor JM, Warwick J, et al; Treatment of post-transplant premalignant skin disease: a randomized intrapatient comparative study of 5-fluorouracil cream and topical photodynamic therapy. Br J Dermatol. 2007 Feb;156(2):320-8. [abstract]
12. Calzavara-Pinton P, Venturini M, Sala R; Photodynamic therapy: update 2006 Part 2: Clinical results. J Eur Acad Dermatol Venereol. 2007 Apr;21(4):439-51. [abstract]
13. Borelli C, Herzinger T, Merk K, et al; Effect of subcutaneous infiltration anesthesia on pain in photodynamic therapy: a controlled open pilot trial. Dermatol Surg. 2007 Mar;33(3):314-8. [abstract]
14. Mooney M; Mohs Micrographic Surgery; emedicine February 2009

Internet and further reading

• Guidelines for management of Bowen's disease, British Association of Dermatologists (2006)
• Welch ML; Bowen Disease; emedicine July 2008
• DermnetNZ; Bowen's Disease non genital
• DermnetNZ; Bowen's Disease of Penis
• DermnetNZ; Bowen's Disease of Vulva

Acknowledgements