Metastasis to the penis from a bladder carcinoma invading only the lamina propria: case report and description of the morphological aspects

Introduction: Data shows that bladder cancer (BC) takes the seventh place as the most commonly diagnosed when it comes to the male population. Whereas when both genders considered, it moves down the tenth place. Although 75% of patients with BC present with the disease confined to the mucosa or submucosa, rarely secondary metastasis to the penis occurs. Case presentation: A 73-year-old male was referred for gross hematuria in May 2018. A cystoscopy was performed detecting a bladder tumor. The resection of the tumor revealed an invasive high-grade (HG) papillary transitional carcinoma of the bladder with nest variants and lamina propria invasion. The histological examination of the second-look resection disclosed the same tumor characteristics. The patient was scheduled for bacillus Calmette–Guérin (BCG) instillations. Meanwhile, he was diagnosed and treated for a primitive lung acinar adenocarcinoma. Seven months after the first diagnosis, the patient progressed to cT4 at the level of the bladder. He underwent four cycles of Methotrexate, Vinblastine, Doxorubicin (Adriamycin) and Cisplatin (MVAC) chemotherapy followed by a cystoprostatectomy. The histological result was fibrosis and ypT0pN0 classification. Due to pain and solid mass in the penis, a total penectomy was performed and the histological result showed a transitional carcinoma suggesting a metastasis of the urothelial carcinoma of the bladder. Three months following the penectomy, a positron emission tomography/computed tomography (PET/CT) scan results showed multiple metastases and positive lymph nodes. Hence, Pembrolizumab treatment was started, providing very good clinical and radiological evolution. At the time of publishing, the patient is alive, and the radiological exams show stability of the disease. Conclusions: The detailed descriptions of all histological variants of carcinoma of the bladder in the specimen has great importance and significant impact on the management of the disease.