An Atypical Presentation of Muscle-Invasive Papillary Urothelial Carcinoma Mimicking Extensive Urethral and Bladder Calculi: A Case Report.

Bladder cancer commonly presents with haematuria, but its clinical features can vary, and unusual presentations may delay diagnosis. Papillary urothelial carcinoma (PUC) is a frequent subtype, typically arising from the bladder urothelium. While most cases are detected through standard urological symptoms and imaging, the presence of extensive urethral and bladder calculi can obscure the underlying pathology. We describe a 45-year-old man with a history of recurrent urinary stone passage who presented with haematuria following expulsion of a large urethral calculus. Examination revealed palpable stones along the urethra, and imaging demonstrated multiple sizeable, calcified lesions within the bladder and urethra. Cystoscopy confirmed complete obstruction of the penile and bulbar urethra by stones, which were removed cystoscopically. A large calcified intravesical mass was subsequently excised. Histopathological analysis identified high-grade PUC with invasion of the muscularis propria. The patient received intravesical mitomycin C one day after resection, prior to histology results, which showed muscularis propria involvement. The patient underwent further staging with pelvic MRI, which showed no evidence of advanced or metastatic disease, and a computed tomography urogram to visualise the upper tract, which showed no further stones or masses in the kidneys, ureters or collecting system and complete resection of bladder mass. At follow-up, he remained clinically stable with no signs of recurrence or evidence of metastasis. This case highlights an uncommon presentation of muscle-invasive PUC concealed by extensive calculi. It emphasises the importance of maintaining diagnostic vigilance in patients with persistent or atypical urolithiasis and demonstrates the value of early histopathological evaluation and timely postoperative intravesical therapy.