睪丸瀰漫性大型B細胞淋巴癌於年輕男性之罕見病例報告

薛丞勛、陳生文、程威銘、張彰琦

臺北市立聯合醫院忠孝院區外科部泌尿科

A Case Report: Primary Testicular Diffuse Large B Cell Lymphoma in a 36-year-old man

Cheng-Hsun Hsueh, Sheng-Wen Cheng, Wei-Ming Cheng, Chang-Chi Chang

Division of Urology, Department of Surgery, Zhongxiao Branch, Taipei City Hospital

Introduction

Primary testicular lymphoma (PTL) is a rare and aggressive form of extranodal non-Hodgkin lymphoma[1]. It accounts for approximately 1–2% of all non-Hodgkin lymphomas and 1–9% of testicular malignancies. Among the various subtypes of PTL, diffuse large B-cell lymphoma (DLBCL) is the most prevalent, representing over 80% of cases[2]. DLBCL is further classified based on its cellular origin into germinal center B-cell (GCB) and non-GCB subtypes, with the latter associated with a poorer prognosis.[3] PTL typically presents in older individuals, with the median age at diagnosis ranging from 66 to 68 years, making it an uncommon diagnosis in younger men[4]. This report presents a case of primary testicular DLBCL of the non-GCB subtype in a 36-year-old male who underwent radical orchiectomy.

Case presentation

A 36-year-old male with no significant medical history presented with a painless, hard mass in the left testicle, which had been present for one month. Physical examination revealed no palpable lymphadenopathy, and the right testicle was unremarkable. Tumor markers, including alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (β-HCG), and lactate dehydrogenase (LDH), were all within normal limits. Testicular ultrasonography was performed on two occasions, demonstrating a rapidly growing heterogeneous and hypervascular mass, which increased in size from 3.72 cm × 1.64 cm to 4.02 cm × 2.10 cm over the course of 10 days. Contrast-enhanced computed tomography (CT) imaging revealed a 23 × 26 mm lobulated nodule in the left scrotum, without evidence of regional lymphadenopathy. The patient underwent left radical orchiectomy via an inguinal approach. Final pathological examination confirmed the diagnosis of diffuse large B-cell lymphoma, non-germinal center B-cell (GCB) subtype. The surgical margin of the spermatic cord was clear of tumor involvement. Immunohistochemical staining of the tumor cells showed positive expression for CD79a, CD20, MUM1, BCL-2, BCL-6, and CD45. In contrast, markers for CD3, CD10, CD30, CD56, cytokeratin (CK), CD117, and placental alkaline phosphatase (PLAP) were negative. The postoperative course was uneventful, and the patient made a full recovery. He was subsequently referred to a hematologist for further combined chemotherapy and targeted therapy with the R-CHOP regimen, consisting of rituximab, cyclophosphamide, doxorubicin, prednisone, and vincristine.

Conclusion

Primary testicular lymphoma, although rare, is a highly aggressive testicular malignancy with a poor prognosis. The occurrence of PTL in young men is exceedingly uncommon. Currently, the understanding of risk factors and molecular mechanisms underlying PTL in this age group remains limited. Further research is necessary to gain deeper insights into the pathophysiology and potential therapeutic strategies for PTL, particularly in younger patients.