Urothelial carcinoma is a complex malignancy often involving progression and invasion, requiring multidisciplinary treatment. We report a 63-year-old Asian male with high-grade left ureteral urothelial carcinoma, treated with nephroureterectomy and chemoradiotherapy in 2013. Later, he developed a prostatic urethral tumor, progressing to stage III bladder cancer with prostate involvement. This case highlights the integration of surgery, chemotherapy, and immunotherapy for effective disease control and bladder preservation, offering insights into managing advanced urothelial carcinoma with atypical progression.

A 63-year-old Asian male with a history of left ureteral infiltrating urothelial carcinoma, high-grade, pT3N0M0, stage III, underwent left nephroureterectomy and concurrent chemoradiotherapy (CCRT) in October 2013. His medical history also includes hypertension, type 2 diabetes mellitus, and coronary artery disease. During routine follow-up cystoscopy, a papillary tumor was identified in the prostatic urethra (Fig.1) Subsequent transurethral resection of the prostatic urethral tumor was performed, and the pathology report confirmed high-grade invasive papillary urothelial carcinoma with prostate stromal invasion, indicating stage III bladder cancer.

The patient then received four cycles of gemcitabine plus cisplatin combined with pembrolizumab from March to May 2022. A follow-up pelvic MRI revealed an ill-defined infiltrating tumor in the central periurethral prostate (Fig.2,3), with no evidence of further progression or distant metastasis. After discussion with the patient, a robotic-assisted laparoscopic radical prostatectomy with standard pelvic lymph node dissection was successfully performed. During the procedure, intravesical instillation of mitomycin for approximately 30 minutes was administered. The final pathology report confirmed high-grade invasive urothelial carcinoma of the prostatic urethra, staged as pathological stage II (pT2N0), with no malignancy detected in the bilateral seminal vesicles or lymph nodes. The surgical margins were clear. Following the robotic-assisted radical prostatectomy, adjuvant nivolumab was administered from July to October 2022. To date, regular follow-up cystoscopy and urinary cytology every three months, along with imaging studies every four to six months, have shown no evidence of tumor recurrence.

This case shows the success of a combined treatment approach for advanced urothelial carcinoma with prostate invasion. Using transurethral resection, chemotherapy (gemcitabine and cisplatin), immunotherapy (pembrolizumab and nivolumab), and robotic-assisted radical prostatectomy, the patient achieved a positive outcome with no tumor recurrence and preserved bladder function. It highlights the value of personalized multimodal therapy and regular follow-up for optimizing long-term results in complex urothelial cancers.