What is bowenoid papulosis?
Bowenoid papulosis is a sexually transmitted infection that presents as pigmented genital papules due to human papillomavirus (HPV) infection with histology closely resembling squamous cell carcinoma-in-situ (Bowen disease). It is now classified as a vulval or penile high-grade squamous intraepithelial lesion (HSIL) and 'bowenoid papulosis' is no longer used by pathologists in the WHO Classification of Tumours, 2020 5th edition.
Who gets bowenoid papulosis?
Men and women are equally at risk and the peak incidence is in sexually active persons under 30 years of age.
Bowenoid papulosis in a child should trigger a suspicion of sexual abuse.
What causes bowenoid papulosis?
Bowenoid papulosis is due to infection with high-risk epithelial/mucosal HPV types, particularly HPV 16. It is spread by close skin-to-skin contact usually during sexual intercourse. [see Sexually acquired human papillomavirus]
What are the clinical features of bowenoid papulosis?
Bowenoid papulosis most commonly involves the anogenital area, but extragenital disease is reported. It typically presents as solitary or multiple small pink, brown, or violaceous papules or plaques on the penis or vulva. Although the glans penis, foreskin, and vulval labia are the most common sites affected, bowenoid papulosis may present on other parts of the genitals, around the anus, or oral cavity. It is usually asymptomatic but lesions can become inflamed, itchy, and painful.
Dermoscopy of genital bowenoid papulosis
Diagnostic dermoscopic features have yet to be determined as there have been only a small number of descriptions. Reported features are not yet consistent but have included:
- Males - pigmented papillomatous or keratotic surface, widespread dotted vessels, brown-grey dots in a linear pattern, structureless areas, lack of pigment network
- Females - exophytic papillary surface structures, glomerular and hairpin vessels, grey-brown structureless areas.
What are the complications of bowenoid papulosis?
Bowenoid papulosis is a sexually transmitted infection (STI) so sexual partners can be infected with the high-risk HPV, increasing their risk of cervical, vaginal, vulval, or penile intraepithelial neoplasia or invasive squamous cell carcinoma. Concurrent HPV-related intraepithelial neoplasia in other anogenital sites can occur. Infection of extragenital sites usually follows genital disease.
Bowenoid papulosis is classified as a high-grade squamous intraepithelial lesion (HSIL) due to a high-risk HPV. It can therefore progress to squamous cell carcinoma particularly in immunocompromised patients, or older patients with large lesions.
How is bowenoid papulosis diagnosed?
Bowenoid papulosis may be suspected based on its typical clinical appearance and dermoscopy.
Skin biopsy is recommended to confirm the diagnosis. [see Squamous cell carcinoma in situ pathology] Features that help to distinguish bowenoid papulosis from Bowen disease include sparing of the hair follicles and gland ducts, dysplastic keratinocytes scattered through the epidermis, keratinocytes in mitosis especially metaphase. p16 Immunohistochemistry shows strong diffuse staining throughout the lesion which helps to distinguish from condyloma acuminatum which may show only focal positivity.
What is the differential diagnosis of bowenoid papulosis?
- Anogenital warts
- Dermatoses - lichen planus, lichen simplex
- Bowen disease
What is the treatment for bowenoid papulosis?
Bowenoid papulosis may be monitored rather than actively treated. Monitoring in females patients and partners of male patients should include vaginal speculum examination and cervical smear.
Treatment is as for anogenital warts. Electrodessication, laser destruction, and cryotherapy are reported to be effective. However recurrence is common as bowenoid papulosis is typically a multifocal infection.
Regular checks are necessary after treatment to ensure the condition has completely resolved.
Can bowenoid papulosis be prevented?
All current vaccines against human papillomavirus cover the high-risk HPV types 16 and 18, and the nonavalent Gardasil-9 protects against a further five high-risk HPV types. Immunisation of children and young teenagers prior to becoming sexually active should prevent infection with most HPV types associated with bowenoid papulosis.
What is the outcome of bowenoid papulosis?
Despite the malignant pathology, bowenoid papulosis often follows a benign course, resolving with or without treatment. Bowenoid papulosis is said to resolve spontaneously after childbirth in young women.
The risk of penile squamous cell carcinoma has been estimated to be 30%, increasing with duration of disease.