Efficacy of Alternative and Other Treatments According to GRADE* Ranking:

Photodynamic Therapy:

Recommendation: Strong (Photodynamic therapy is effective as a potential treatment for Bowens disease)

Grade of Evidence: Strong quality of evidence

 * www.gradeworkinggroup.org

Bowen's disease

Bowen's disease is a form of skin cancer characterized by slow-growing and red, scaly skin patch usually found on the lower leg. It is also called Squamous Cell Carcinoma (SCC) in situ. ^[1] The disease was first described by the American dermatologist John T. Bowen in 1912. Bowen's disease has the potential for significant lateral spread where larger lesions can measure up to several centimetres in diameter.^[2]

Epidemiology

The prognosis for Bowen's disease is good with a risk of progression to invasive SCC at 3-5% in majority of studies conducted. The disease is usually reported in sun-exposed body parts of white individuals. In patients with darker-pigmented skin however, it usually affects the nonexposed sites.  Male to female ratio is equal. In males, common sites are head and neck while lower limbs and cheeks are the usually affected in women . The disease occurs in adulthood. Highest incidence occurs in patients older than 60 years. ^[2]

Causes

Bowen's disease is thought to develop as a result of long-term sun exposure. On very rare occasions, it may be due to previous radiotherapy, chronic arsenic ingestion or on the genitalia in association with the Human Papilloma Virus (HPV), a kind of virus that causes warts. The disease is neither caused by allergy nor by infection.^[3]  

Risk factors

Bowen's disease is more common in females and people over 40 years of age. The condition is also more reported in sunny countries. People exposed to arsenic are at risk. ^[4]

Signs and Sympoms

Affected person has a single or multiple scaly, red and flat or slightly raised patches appear that grow very slowly. The edges are irregular but distinct from the surrounding skin. Any part of the body can be affected but the most usual site is the lower leg. The patches can be sore, become irritated or may bleed.^[4]

Diagnosis

After assessing the history and doing a physical examination, a skin biopsy is often done.^[5]

Treatment

The most common treatment for smaller lesions is surgical excision.^[6] Since Bowen's disease grows very slowly, observation and close monitoring may be the only medical advise given especially to patients with skin healing problems. Other treatment options are curettage, electrocautery, creams or topical therapy, photodynamic therapy, cryotherapy and laser treatment.^[5]

References:

1. http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Bowen%27s_disease?open
2. http://emedicine.medscape.com/article/1100113-overview
3. http://www.bad.org.uk/site/802/default.aspx
4. http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Bowen%27s_disease?open
5. http://www.macmillan.org.uk/Cancerinformation/Cancertypes/Skin/Pre-cancerousconditions/Bowensdisease.aspx
6. http://www.aocd.org/skin/dermatologic_diseases/bowens_disease.html

Summary References
Treatments:
1. http://www.merck.com/mmpe/sec10/ch128/ch128c.html