膀胱罕見發炎性肌纖維母細胞瘤以銩雷射施行整塊切除之成功病例報告

陳穎政^1,2、黃上瑋²、周孟翰²

¹國軍桃園總醫院 外科部 泌尿外科；²國防醫學大學三軍總醫院 外科部 泌尿外科

Successful En Bloc Thulium Laser Resection of a Rare Inflammatory Myofibroblastic Tumor of the Urinary Bladder

Ying-Zheng Chen^1,2, Shang-Wei Huang², Meng-Han Chou²

¹Divisions of Urology, Department of Surgery, Taoyuan Armed Forced General Hospital, Taiwan, ROC ;

²Divisions of Urology, Department of Surgery, Tri-Service General Hospital, National Defense Medical University, Taipei, Taiwan, ROC.

Abstract

Inflammatory myofibroblastic tumors (IMTs) of the bladder are rare mesenchymal neoplasms characterized by spindle cell proliferation and chronic inflammatory infiltrates. They account for less than 1% of bladder tumors and are most commonly observed in adults aged 20–40 years. This report details the case of a 46-year-old male presenting with several days of hematuria. Computed tomography subsequently revealed irregular thickening of the right anterior bladder wall, leading to suspicion of a bladder tumor. The patient underwent transurethral resection of the bladder tumor, and the final pathology revealed an IMT with anaplastic lymphoma kinase (ALK) positivity. Instead of partial cystectomy, en bloc resection using a thulium laser was employed to reduce recurrence and preserve bladder capacity. Diagnosis of bladder IMTs is challenging because of the overlapping histological features of malignant spindle cell tumors. Immunohistochemical staining plays a crucial role in differentiation, with approximately 50% of cases exhibiting anaplastic lymphoma kinase (ALK) expression. Fluorescence in situ hybridization can be used to detect ALK rearrangements. Despite its generally benign nature, IMT can exhibit local recurrence (4%) and malignant transformations in rare instances. Continuous surveillance is necessary to monitor recurrence and progression. In our case, a large IMT of the bladder can be effectively excised en bloc using a thulium laser, facilitating complete tumor removal and potentially reducing the risk of recurrence.