Incidental Finding of an Inflammatory Myofibroblastic Tumor of the Urinary Bladder: A Case Report.

Bladder inflammatory myofibroblastic tumors (IMTs) are rare lesions with intermediate malignant potential and unclear management guidelines. We report the case of a 61-year-old male presenting with lower urinary tract symptoms and a bladder mass. Histology revealed spindle cells with mild atypia and chronic inflammation, and anaplastic lymphoma kinase (ALK) positivity suggested a TPM3-ALK fusion. The tumor was completely resected via transurethral resection of the bladder tumor (TURBT), with no recurrence at the six-month follow-up. This case illustrates the diagnostic complexity of bladder IMTs and emphasizes the importance of histopathology and close surveillance due to the risk of recurrence and rare metastasis.