Carcinoma of the penis

Primary carcinoma of the penis is a rare tumor disease that mainly occurs in older men. It is associated with several risk factors including (untreated) phimosis, infection with human papillomavirus, and smoking. Patients present with a lump or an ulcerative lesion of the penis. Palpation of the groin and physical examination may reveal enlarged inguinal lymph nodes. Excisional biopsy is performed for histopathological confirmation of the tumor while MRI of the penis and CT of the pelvis are part of the tumor staging. The primary treatment is usually surgical and depends on the extent of the local and regional disease; options include local excision and partial or radical penectomy. Regional lymph node dissection may be necessary if the inguinopelvic nodes are involved. Metastatic disease is rare at inital presentation, but chemotherapy may be a palliative option. The overall prognosis is determined by the presence and extent of regional lymph node involvement.

• Rare type of malignancy in industrialized countries
• More common in low-income regions with poor hygienic conditions, esp. in Africa, South America, and Asia
• Peak incidence: 60 years of age ^[1]

Epidemiological data refers to the US, unless otherwise specified.

Chronic inflammation of the penis

• Risk factors ^{[2] [1]}
  • Phimosis, particularly if left untreated
  • Tobacco use
  • Infections
    • Human papillomavirus; (HPV) infection, especially type HPV-16 and HPV-18
    • HIV
    • Precancerous skin lesions (see “Differential diagnoses” below)
• Protective factor: circumcision before adulthood

• Palpable painless lump or ulcerative lesion of the penis ^[3]
  • The glans and the foreskin are the most common locations.
  • A concurrent phimosis may conceal the lesion
  • Surface of the lesion may be exophytic, flat, or ulcerated
• Chronic penile rash or subtle burning sensation
• Voiding and sexual function typically remain unimpaired
• Swollen inguinal lymph nodes ^[2][4]

• Excisional biopsy (gold standard)
  • ∼ 95% of all penile cancers are squamous cell carcinoma (SCC): atypical squamous cells with varying degrees of mitotic activity ^[5]
• Tumor staging ^[3]
  • Fine needle aspiration, biopsy or dissection of inguinal lymph nodes
  • Imaging studies
    • Ultrasonography and/or MRI of the penis and pelvis
    • Pelvic CT ^[2][4]

• Benign tumors or lesions ^[3]
  • Condylomata acuminata
  • Buschke-Löwenstein tumor
  • Sexually transmitted infections
• Precancerous skin lesions or carcinoma in situ lesions
  • Bowen disease :
  • Erythroplasia of Queyrat
  • Bowenoid papulosis
  • Leukoplakia
• Metastases ^[4]

The differential diagnoses listed here are not exhaustive.

Treatment depends on the stage of the disease and the risk of recurrence, but the initial approach is typically surgical. ^[4][6]

• Small (< 3cm) primary tumors
  • Limited local excision with or without circumcision
  • Laser ablation
  • Radiation therapy
• Invasive or bulky primary tumors
  • Partial penectomy: if penile length is adequate (e.g., for voiding, sexual activity) after excision with a 2 cm surgical margin
  • Total penectomy and perineal urethrostomy
  • Regional ipsilateral lymph node dissection in patients with positive lymph nodes often followed by adjuvant chemotherapy
• Recurrent or metastatic disease: penectomy or palliative chemotherapy

• Prognosis is determined primarily by the presence and the extent of inguinal lymph node involvement. ^[7]
• 5-year overall survival rates for locally-confined tumors and advanced tumors: 85% and < 60%