Late Penile Urethral Involvement of Urothelial Carcinoma After Radical Cystectomy: Diagnostic Challenge in Distinguishing Urethral Recurrence From Metastatic Disease.

Penile involvement of urothelial carcinoma is a rare clinical entity typically arising from primary pelvic tumours and is usually associated with advanced disease and poor prognosis. However, distinguishing between true penile metastasis and late urethral recurrence is challenging, particularly in patients with urethral preservation after radical cystectomy (RC). We report the case of a 77-year-old male with a history of high-grade invasive urothelial carcinoma (pT2a N0) with concomitant carcinoma in situ (CIS), treated with RC and uretero-ileal urinary diversion with urethral preservation. Ten years after surgery, the patient presented with a painful mass at the base of the penis accompanied by solid urethral discharge. Biopsy of the urethral content confirmed high-grade papillary urothelial carcinoma (G3) with invasion of the lamina propria. Multimodal imaging studies demonstrated a solid tumour involving the proximal third of the penile urethra with extension into the corpus spongiosum and tunica albuginea, alongside a suspicious left inguinal lymph node. The patient underwent radical penectomy and left laparoscopic inguinal lymphadenectomy. Histopathological examination confirmed high-grade invasive urothelial carcinoma of the penile urethra, invading the corpus spongiosum and tunica albuginea (pT2 N0), with free surgical margins. Immunohistochemical profiling was not performed due to limited archival material, preventing definitive distinction between urethral recurrence and metastatic disease. No adjuvant systemic therapy was administered. At 2 years of follow-up, the patient remains disease-free on surveillance imaging. This case highlights the unusual late presentation of urothelial carcinoma involving the penis and underscores the diagnostic challenge in distinguishing urethral recurrence from true metastatic disease in the absence of molecular data. Long-term surveillance, including thorough physical examination, is essential even many years after initial treatment.