What is the recommended management for penile adenocarcinoma?

Management of Penile Adenocarcinoma

Penile adenocarcinoma requires aggressive surgical excision as primary treatment, as this rare histologic subtype represents metastatic disease from another primary site (most commonly gastrointestinal or genitourinary) rather than a primary penile malignancy, and carries an extremely poor prognosis with median survival of 7 months to 2 years. 1

Critical Initial Assessment

Penile adenocarcinoma is almost always metastatic disease—you must identify the primary source immediately. The most common origins are:

• Rectal/colorectal adenocarcinoma (most frequent gastrointestinal source) 1
• Bladder and prostate (most common genitourinary sources) 1
• Lung, nasopharynx, and melanoma (less common) 1

Diagnostic Workup

• Obtain tissue diagnosis via punch, excisional, or incisional biopsy to confirm adenocarcinoma histology 2
• Perform comprehensive staging imaging: CT chest/abdomen/pelvis to identify the primary tumor and extent of metastatic disease 1
• Consider PET/CT for complete metastatic evaluation, as it has shown good sensitivity for M-staging 3
• Document physical characteristics: diameter, location, number of lesions, morphology, and relationship to anatomical structures including urethra, corpora spongiosa, and corpora cavernosa 2

Treatment Algorithm

If Penile Metastasis is the ONLY Site of Recurrence

Proceed with penile amputation (partial or total) for potential long-term survival. 1

• This is the only scenario where aggressive local treatment may provide curative benefit
• One case report documented 9-year survival after penile amputation when the penis was the sole site of recurrence 1
• Ensure negative surgical margins with adequate resection 1

If Widespread Metastatic Disease is Present

Treatment is palliative, not curative. 1

• Systemic chemotherapy: Use cisplatin-based regimens (TIP: paclitaxel, ifosfamide, cisplatin) as first-line treatment 2
• Alternative regimen: 5-fluorouracil plus cisplatin can be considered, though toxicities may be significant 2
• Avoid bleomycin-containing regimens due to high pulmonary toxicity and fatalities 4
• Local palliative measures:
  • Suprapubic cystostomy for urinary obstruction 1
  • Palliative radiation therapy for unresectable lesions or symptomatic bone metastases 2

Management of Specific Complications

Urinary Obstruction

• Perform suprapubic cystostomy when the entire penile shaft becomes indurated and causes urinary retention 1
• This is a common late complication as metastatic disease progresses 1

Malignant Priapism

• Major presenting symptom in some cases of penile metastases 1
• Requires urgent urologic consultation for decompression and pain management

Prognosis and Counseling

The prognosis is extremely poor regardless of treatment modality. 1

• Median survival: 7 months to 2 years from diagnosis of penile metastasis 1
• Timing: Penile metastases from rectal adenocarcinoma typically occur within 2 years after diagnosis of the primary tumor 1
• Best outcomes: Achieved only when penile metastasis is the sole site of recurrence and aggressive surgical treatment (penile amputation) is performed 1

Critical Pitfalls to Avoid

• Do not mistake this for primary penile squamous cell carcinoma—the NCCN guidelines for primary penile cancer do not apply to adenocarcinoma, which is metastatic disease 2
• Do not delay staging workup—identifying the primary source and extent of disease determines whether any curative-intent treatment is possible 1
• Do not perform organ-sparing approaches—these are inappropriate for metastatic adenocarcinoma 1
• Do not offer false hope—survival beyond 2 years is exceptional even with aggressive treatment 1