Inflammatory myofibroblastic tumor of the bladder turn malignant: A case report

Introduction and importance: Inflammatory myofibroblastic tumor (IMT) of the bladder is a rare sight, which can be distinguished by the proliferation of spindle cells and the presence of a persistent chronic inflammatory infiltrate. IMT is usually benign, but in a few cases it has a tendency for malignant transformation and metastases. Case presentations: A 30-year-old male with a history of recurrent hematuria. His initial symptoms was unfrequent painless hematuria. Abdomen multislice computerized tomography (MSCT) with contrast shows an enhancing solid mass with necrotized center measuring +/− 12.9 × 16.5 × 18.9 cm and extending from cavum pelvis to cavum abdomen. Cystectomy and bilateral ureterocutaneostomy were performed. The histology report found an IMT with mitotic cells, a necrotic region, and a positive ki67, which suggest the tumor's malignant transformation. Unfortunately, the patient's overall condition continued to deteriorate, and he passed away seven days after hospital discharge. Clinical discussions: IMT is comprised of spindel cells and inflammatory cells. IMT might become aggressive locally, recurring, or progress to malignancy. Fifty percent of IMTs are caused by rearrangements of the anaplastic lymphoma kinase (ALK) gene on chromosome 2p23, resulting in ALK-1 overexpression. A change from uniform spindled cells to atypical polygonal cells or plump cells with oval vesicular nuclei, prominent nucleoli, and mitoses is indicative of malignant transformation. Conclusion: This case emphasizes the importance of continuous monitoring and raising awareness about the possibility of malignant transformation of IMT. Understanding the characteristics of the findings could result in better decision-making and outcomes.