陳威任¹、林志杰^{1, 2, 3}、林登龍^{1, 2, 3}、陳光國^{1, 2, 3}

¹臺北榮民總醫院泌尿部；²國立陽明大學醫學系泌尿學科；³書田泌尿科學研究中心

Inflammatory myofibroblastic tumor of urinary bladder in a patient with human immunodeficiency virus – a rare case report and literatur review
Wei-Jen Chen¹, Chih-Chieh Lin ^{1, 2, 3}, Alex T. L. Lin^{1, 2, 3}, Kuang-Kuo Chen^{1, 2, 3}

Department of Urology, Taipei Veterans General Hospital¹; Department of Urology, School of Medicine, National Yang-Ming University²; Shu-Tien Urological Science Research Center³

 

Inflammatory myofibroblastic tumor (IMT) is a rare tumor with a generally indolent, but sometimes aggressive behavior. It had been described in major organs. The first case of IMT of the bladder was reported in 1980. Until recent 15 years, IMT have gained a distinct entity with established characteristic features in pathological diagnosis. Reported literatures are limited in case report and case series. A systemic review article published in 2014 presented a total of 182 patients with IMT in urinary bladder. However, there is no related literature in patient with human immunodeficiency virus (HIV). Here, we report a HIV patient with IMT of the urinary bladder and discuss its clinical presentation, diagnosis and management.

A 45 year-old HIV infected man, came to our outpatient department due to painless gross hematuria with repeated urine retention for 3 months, anemia, and body weight loss 9 kgs. Except HIV infection, he had no other systemic disease. Due to detectable HIV viral load, the operation was delayed before visiting us. CT scan was done two months ago, revealing a 5cm, round, heterogenous enhancement tumor, without lymphadenopathy. In our institute, transurethral resection of the bladder tumor (TURBT) was soon arranged after confirming his HIV viral load was undetectable. A large, broad-based, non-papillary tumor grew from bladder posterior wall was confirmed during the operation. However, the tumor size was much larger then 5cm, which showed on the CT scan 2 months ago, and the total resected specimen was finally estimated to be 680 gm. After the operation, patient’s recovery was smooth, and he was discharged on post-operative day 7. Final pathology report revealed inflammatory myofibroblastic tumor. There’s no muscle invasion. Due to large broad-based tumor, and prolonged operation time with possible incomplete resection during 1^st TURBT, 2^nd-look TURBT was arranged one month later, and residual 35gm tumor was resected. The pathology report was the same.

IMT is a rare tumor, and had been variously named before, such as inflammatory pseudotumor, plasma cell granuloma, atypical myofibroblastic tumor, and atypical fibromyxoid tumor. The pathogenesis of IMT remains obscure, with possible etiologies including autoimmune disease and infectious organisms. Controversy still exists that thether IMT is a truly neoplastic process, since its clinical course is generally indolent after surgical resection. Report showed local recurrence rate about 10%. No distant metastasis had been reported currently. Image findings are nonspecific and histologic confirmation is essential. The diagnosis should be differentiated from sarcomatoid carcinoma and leiomyosarcoma.

IMT had been reported in lung, liver, spleen, testis, larynx, small bowel, CNS, lymph nodes, soft tissue of HIV/AIDS patients. To our best knowledge, this is the first case report of bladder IMT in an HIV patient. Some author suggested that IMT may be related to immune reconstitution inflammatory syndrome (IRIS) in HIV-infected patients receiving HAART, which is an augmentation of inflammation that can occur during immune reconstitution in an immunocompromised host. However, due to rarity of the cases, whether the incidence of IMT is higher in HIV patients is unclear.