Bowens Disease: Symptoms, Types, Causes and Treatment

Bowen's disease, also known as squamous cell carcinoma in situ, is a form of early skin cancer that remains confined to the epidermis. Although it’s considered an early stage, if left untreated, it can progress to invasive squamous cell carcinoma. This comprehensive guide covers its symptoms, types, causes, and treatment, synthesizing the latest evidence to help patients and caregivers understand this important dermatological condition.

Symptoms of Bowens Disease

When dealing with a skin condition like Bowen’s disease, recognizing the symptoms is the first step towards timely diagnosis and effective management. The disease can be subtle at first, but certain features should raise suspicion, especially for persistent, slow-growing patches on the skin.

Appearance	Location	Sensation	Citation
Red, scaly patch	Sun-exposed areas	Usually painless	4 6 7
Well-defined plaque	Head, neck, limbs	Sometimes itchy, sore	4 5 6
Pigmentation	Genital, perianal, or nail	Pain, bleeding, or lump	3 5 10 13
Nail changes (melanonychia, dystrophy)	Nail matrix	Nail discoloration or deformity	1 13

Table 1: Key Symptoms

Classic Symptoms

The hallmark of Bowen’s disease is a well-circumscribed, slowly enlarging, red or erythematous scaly patch or plaque. These lesions are usually flat or slightly elevated, with a rough surface and irregular but sharply demarcated borders. Most cases are painless and may be discovered incidentally during a routine skin check. However, some people might experience mild symptoms like itching or irritation 4 6 7.

Site-Specific Features

• Sun-exposed Areas: The most common locations are the head, neck, and limbs—areas typically exposed to sunlight. In women, the lower limbs are particularly affected, while in men, the scalp and ears are more frequently involved 6.
• Unusual Locations: Bowen’s disease can also appear in less common sites, including the genitalia, perianal region, and under the nails (subungual Bowen’s disease) 3 5 13.

Uncommon Presentations

• Pigmented Lesions: Some variants present as brown or black plaques, mimicking other pigmented skin conditions 9 10.
• Nail Changes: When affecting the nail matrix, it may cause longitudinal melanonychia (a dark streak along the nail) or nail dystrophy 1 13.
• Genital and Perianal Symptoms: Lesions in these regions may present with pain, itching, bleeding, or the feeling of a lump 3 5.

Symptom Progression

Bowen’s disease is generally slow-growing. Symptoms may persist for months or years before diagnosis. Rarely, if left untreated, the lesion can become invasive, resulting in new symptoms such as ulceration, increased pain, or bleeding 4 7. Any non-healing or changing skin lesion warrants medical evaluation.

Types of Bowens Disease

Bowen’s disease is not a one-size-fits-all diagnosis. Several clinical and histological types exist, each with distinct features and implications for management.

Type	Description	Common Sites	Citation
Classic (Non-pigmented)	Red, scaly patch or plaque	Sun-exposed skin	4 6 9
Pigmented	Brown/black, well-defined plaque	Face, limbs, rarely elsewhere	9 10
Genital/Perianal	Lesion in anogenital region	Vulva, anus, perianal	3 5
Subungual	Nail involvement, melanonychia	Nail matrix	1 13
Follicular	Deep follicle involvement	Face, neck	14

Table 2: Types of Bowen’s Disease

Classic (Non-pigmented) Bowen’s Disease

This is the most common form, displaying as a solitary, erythematous, scaly patch or plaque, typically on sun-exposed areas like the head, neck, arms, and legs. It is often mistaken for eczema or psoriasis 4 6.

Pigmented Bowen’s Disease

A rarer form, pigmented Bowen’s disease presents as a dark brown or black plaque, which can be mistaken for melanoma or other pigmented lesions. Dermoscopic evaluation helps distinguish it, though sometimes findings are non-diagnostic 9 10.

Genital and Perianal Bowen’s Disease

These variants affect the mucosal or semi-mucosal areas such as the vulva, penis, or perianal skin. They may be associated with high-risk human papillomavirus (HPV) infection and have an increased risk of progression to invasive carcinoma 3 5.

Subungual (Nail) Bowen’s Disease

A less common type, this appears as longitudinal melanonychia (dark streak along the nail) or nail dystrophy. It often requires a high index of suspicion and biopsy for diagnosis 1 13.

Follicular Bowen’s Disease

This rare variant involves the hair follicles more deeply than the classic type. It can be missed clinically and is sometimes only identified on histological examination. Follicular involvement is a known reason for treatment failure with superficial therapies 14.

Causes of Bowens Disease

Understanding the root causes of Bowen’s disease helps in prevention and targeting at-risk populations. Several risk factors and underlying mechanisms have been identified.

Factor	Mechanism/Association	Notable Details	Citation
Sun exposure	DNA damage from UV radiation	Most common cause	4 6 19
Arsenic	Environmental/occupational	High-risk in some regions	2 12 13
HPV infection	Viral oncogenesis	High-risk genital/perianal	5 11 13
Trauma/Radiation	Local tissue damage	Rare triggers	13
Age	Increased risk with age	Elderly more affected	6 19
Immunosuppression	Impaired immune surveillance	Chronic diseases, medications	19

Table 3: Causes and Risk Factors

Sun Exposure and UV Radiation

Chronic exposure to ultraviolet (UV) radiation is the leading cause of Bowen’s disease, particularly affecting sun-exposed areas of fair-skinned individuals. DNA damage from UV rays leads to mutations and dysplastic changes in skin cells 4 6 19.

Arsenic Exposure

Chronic arsenic intoxication, from contaminated water, occupational exposure (e.g., mining), or certain medications, is a well-documented risk factor. Arsenic-related Bowen’s disease often presents alongside other skin changes such as palmar keratosis and “raindrop” pigmentation, and carries a risk for internal malignancies 2 12 13.

Human Papillomavirus (HPV)

HPV plays a significant role, particularly in genital and perianal Bowen’s disease. High-risk types, especially HPV 16 and 18, are most commonly implicated. HPV DNA can also be found in some extragenital cases 5 11 13.

Other Contributing Factors

• Age: The disease is more common in older adults, likely due to cumulative sun exposure and weakened immune surveillance 6 19.
• Immunosuppression: Patients on long-term immunosuppressive therapy or with immunocompromising diseases are at elevated risk 19.
• Trauma and Radiation: Rarely, previous trauma or radiation to the skin can trigger Bowen’s disease at the site 13.

Treatment of Bowens Disease

Bowen’s disease is highly treatable, especially when detected early. The choice of treatment depends on the size, location, number of lesions, patient’s health status, and risk of recurrence. The aim is complete removal or destruction of the lesion with minimal morbidity.

Treatment	Approach	Suitability/Notes	Citation
Surgical excision	Physical removal	High cure rate, for small/accessible lesions	3 4 5 16
Cryotherapy	Freezing with liquid nitrogen	Small or superficial lesions	16 19
Topical 5-FU	Chemotherapy cream	Non-invasive, effective, some recurrence	16 17 19
Imiquimod cream	Immune response modifier	Topical, good for large/poor healing sites	15 16 19
Photodynamic therapy (PDT)	Light-activated photosensitizer	Large or hard-to-treat lesions	16 18 19
Laser/radiotherapy	Targeted ablation	Special cases, recurrences	5 16

Table 4: Treatment Options

Surgical Excision

Surgical removal is the gold standard for accessible or small lesions, offering high cure rates and allowing histological confirmation. Complete excision is crucial to minimize recurrence and prevent progression to invasive carcinoma. Incomplete excision increases the risk of recurrence and metastasis 3 4 5 16.

Topical Therapies

• 5-Fluorouracil (5-FU): This topical chemotherapy agent is effective for superficial Bowen’s disease and is particularly useful for patients who cannot undergo surgery. Long-term studies show low recurrence rates 16 17 19.
• Imiquimod: A topical immune response modifier, imiquimod activates local immune cells to destroy abnormal cells. It is effective for lesions on the lower limbs and other sites where surgery is challenging. Some patients can experience local skin reactions, but response rates are high 15 16 19.

Cryotherapy

Cryotherapy uses liquid nitrogen to freeze and destroy abnormal cells. It is suitable for small, superficial lesions but may be less effective for thicker or follicular-involved disease 16 19.

Photodynamic Therapy (PDT)

PDT involves applying a photosensitizing agent to the lesion, followed by exposure to a specific wavelength of light. This generates reactive oxygen species that selectively destroy abnormal cells. PDT is valuable for large or anatomically difficult lesions and shows high response rates with minimal scarring 16 18 19.

Laser and Radiotherapy

For recalcitrant or recurrent lesions, laser ablation or targeted radiotherapy may be considered. These are also options for patients who are not surgical candidates 5 16.

Other Considerations

• Special Sites: Perianal and subungual (nail) lesions often require individualized treatment plans, sometimes combining therapies or using more aggressive approaches due to risk of recurrence or progression 3 5 13 14.
• Follow-Up: Regular follow-up is essential to monitor for recurrence, new lesions, or progression to invasive cancer 16.

Conclusion

Bowen’s disease is a potentially serious but highly treatable early form of skin cancer. Recognizing its symptoms, understanding the different types and causes, and knowing the available treatment options are critical for effective management. Early detection remains the key to successful outcomes.

Key takeaways:

• Bowen’s disease often presents as a well-defined, scaly red patch or plaque, mainly on sun-exposed skin, but can also occur on the genitalia, perianal area, or nails.
• Multiple types exist, including classic, pigmented, genital/perianal, subungual, and follicular variants.
• Major risk factors include chronic sun exposure, arsenic, HPV infection, and older age.
• Treatments range from surgical excision, topical agents (5-FU, imiquimod), cryotherapy, photodynamic therapy, to laser or radiotherapy.
• Regular follow-up is crucial to detect recurrences or progression to invasive cancer.

Bowen’s disease serves as a reminder of the importance of skin health vigilance and the power of early intervention in preventing more serious disease.