Erythroplasia of Queyrat

What is it?

Erythroplasia of Queyrat is a form of squamous cell carcinoma in situ (a pre-invasive cancer confined to the epithelium) that occurs on the glans penis, prepuce (foreskin), or other mucosal surfaces of the male genitalia. First described by Louis Queyrat in 1911, it is now classified as a clinical variant of penile intraepithelial neoplasia (PeIN). Although the condition remains confined to the epithelium (the surface layer), it carries a significant risk of progression to invasive squamous cell carcinoma if left untreated.

Who is affected?

Erythroplasia of Queyrat is an uncommon condition that predominantly affects middle-aged and older men.

• Prevalence: Penile malignancies overall are rare in Western countries, affecting fewer than 1 per 100,000 males annually; erythroplasia of Queyrat represents a subset of penile intraepithelial neoplasia
• Age demographics: Typically diagnosed in men over 50 years
• Risk factors: Uncircumcised status (prepuce is the most common site); human papillomavirus (HPV) infection—particularly HPV-16 (detected in approximately 49% of cases) and HPV-18; lichen sclerosus (present in 12% of penile intraepithelial neoplasia cases); chronic inflammation or irritation; phimosis; poor hygiene; smoking; immunosuppression

What causes it?

Two distinct etiopathogenic mechanisms have been identified:

• HPV-driven pathway (most common, approximately 84% of cases): Human papillomavirus infection, particularly HPV-16 and HPV-18, drives oncogenic transformation of the epithelial cells; approximately 90% of penile intraepithelial neoplasia cases test positive for HPV
• Non-HPV pathway (approximately 11% of cases): Associated with lichen sclerosus (a chronic inflammatory condition of the genital skin) and chronic irritation
• Additional risk factors: Poor genital hygiene; phimosis (inability to retract the foreskin); immunosuppression; tobacco use

What are the clinical features?

Erythroplasia of Queyrat characteristically presents as a well-defined, persistent red patch on the glans penis or foreskin.

Typical appearance:

• Well-demarcated, erythematous (red), velvety or glistening plaque
• Surface may appear moist and slightly raised
• Usually solitary
• Size varies, typically 1-4 cm in diameter

Symptoms:

• Often asymptomatic in early stages
• Mild pruritus (itching) or burning sensation
• Occasional bleeding or crusting
• Lesions are typically painless and do not affect urinary or sexual function
• Up to 50% of patients delay seeking medical attention for up to one year

How is it diagnosed?

A high index of clinical suspicion is essential, as approximately 25% of penile malignancies are initially misdiagnosed as benign conditions:

• Punch biopsy (gold standard): Histopathological examination reveals full-thickness keratinocyte atypia (abnormal cells throughout the entire epidermis) without invasion beyond the basement membrane; supplemented by p16 and p53 immunostaining and HPV testing
• Dermoscopy: Reveals structureless erythematous areas and dotted vessels, with complete absence of a pigment network; useful for monitoring and follow-up
• Aceto-white testing: Application of acetic acid causes the lesion to turn white, with a high negative predictive value for genital precancerous lesions
• Differential diagnosis: Must be distinguished from Zoon balanitis (plasma cell balanitis), lichen planus, psoriasis, candidiasis, fixed drug eruption, contact dermatitis, and secondary syphilis

What treatment options are available?

Treatment selection depends on lesion extent, location, and patient factors. In a large series of 345 patients, 85.6% ultimately required surgical intervention:

Topical therapies (limited or early disease):

• 5-Fluorouracil (5-FU) cream
• Imiquimod 5% cream: Response rates of 40-100%; recurrence rate approximately 20%

Photodynamic therapy (PDT):

• Aminolevulinic acid or methyl aminolevulinate PDT: Complete remission in 58-63% of cases; may be less effective in HPV-positive lesions

Laser ablation:

• CO2 laser: 81% complete remission after a single session with excellent cosmetic outcomes

Surgical options:

• Circumcision: Effective for preputial (foreskin) lesions; often the primary surgical intervention
• Mohs micrographic surgery: Lowest recurrence rate; provides precise margin control
• Total glans resurfacing: Recurrence rate approximately 5%; excellent cosmetic and functional outcomes
• Glansectomy: Reserved for extensive disease; recurrence rate approximately 10%
• Wide local excision: Recurrence rate approximately 25%

Prognosis:

• If untreated, approximately 30% of cases progress to invasive squamous cell carcinoma
• With appropriate treatment, progression to invasive cancer occurs in only 2.6% of cases
• Long-term follow-up is essential, as recurrence can occur with any treatment modality
• Early detection and treatment result in excellent outcomes

Key points for patients

• Erythroplasia of Queyrat is a pre-cancerous condition that requires treatment to prevent progression to invasive cancer
• Any persistent red patch on the glans penis or foreskin that does not resolve within a few weeks should be evaluated by a dermatologist or urologist
• Biopsy is essential for accurate diagnosis—the condition cannot be diagnosed by appearance alone
• When to seek medical attention: Any persistent red, velvety patch on the genitalia; any non-healing sore or plaque; bleeding or changes in an existing lesion
• Prevention strategies: Practice good genital hygiene; circumcision may be considered a preventive measure; HPV vaccination; regular self-examination of the genital area; prompt treatment of lichen sclerosus; smoking cessation