復發性B細胞淋巴瘤偽裝為實性膀胱腫瘤-案例報告

楊宗道^1,2，張景欣^1,2

臺北醫學大學附設醫院泌尿科,臺北醫學大學泌尿腎臟研究中心

Recurrent B-Cell Lymphoma Mimicking a Solid Urinary Bladder Tumor: A Case Report

Tzung-Dau, Yang^1,2 , Ching-Hsin, Chang^1,2

1.Department of Urology, Taipei Medical University Hospital, Taipei, 11031, Taiwan

2.TMU Research Center of Urology and Kidney, Taipei Medical University, Taipei, 11031, Taiwan

Case report:

A 75-year-old female with a medical history of well-controlled systemic conditions, including Type 2 diabetes mellitus, hepatitis B (carrier status), peptic ulcer, and hypertension, was diagnosed with left neck marginal zone B-cell lymphoma (pT1N0M0, Stage I, Ann Arbor Stage IE) 10 years ago. She received a combination of radiotherapy and chemotherapy, including VPC, Mabthera plus Vincristin/Cyclophosphamide/Compresolon, Mabthera , Endoxan. The patient experienced recurrence of lymphoma in the right inguinal lymph nodes, right external iliac chain, and left axillary lymph nodes, which were detected 7 years ago. Following a series of examinations, including PET-CT and panendoscopy in July 2024, the patient was found to be in complete remission.

Five months later, she presented to our urology outpatient department with gross hematuria and difficult voiding. Sonography revealed right-sided hydronephrosis and a bladder mass measuring 3.1 x 2.4 x 2.8 cm. Cystoscopy confirmed the presence of a large bladder tumor that obstructed the right ureteric orifice. The patient underwent transurethral resection of the bladder tumor, which proceeded without complications. The tumor texture was consistent with that of a prostate adenoma rather than urothelial carcinoma. Postoperatively, the patient's voiding function improved.

Pathological examination of the tumor revealed marginal zone lymphoma. Immunohistochemical analysis showed that the atypical lymphocytes were positive for CD20 and bcl-2, but negative for CD3, CD5, CD10, CD23, CD30, bcl-6, and cyclin D1. Staining with anti-CD23 highlighted the expanded follicular dendritic cell networks within the colonized follicles. The Ki-67 proliferation index was 20%.

Given the findings, the patient was started on further treatment with radiotherapy and chemotherapy.

Discussion:

B-cell lymphoma is the most common subtype of non-Hodgkin lymphoma. Primary lymphoma of the urinary bladder accounts for only 0.2% of extranodal non-Hodgkin lymphomas, while secondary involvement of the bladder by systemic lymphoma is more frequent. Bladder lymphoma has a female predominance, with most cases occurring in middle-aged women. Treatment with radiotherapy has been shown to be effective in managing this condition.