Primary extranodal marginal zone non-hodgkin lymphoma of the prostate: a case report.

This report describes a clinically rare case of early-stage primary extranodal marginal zone B-cell lymphoma of the prostate. A 73-year-old male presented with urinary hesitancy. Physical examination revealed mild prostatic enlargement. Prostate biopsy, immunohistochemistry, and genetic testing strongly suggested mucosa-associated lymphoid tissue (MALT) lymphoma. Bone marrow aspiration indicated no bone marrow involvement. Positron Emission Tomography-Computed Tomography (PET-CT) and Emission Computed Tomography (ECT) scans showed no evidence of involvement in other sites. Ultimately, the patient was definitively diagnosed with primary prostatic MALT lymphoma, Ann Arbor stage IE. He underwent external beam radiation therapy to the prostate, receiving a total dose of 3000 cGy delivered in 15 fractions. During radiotherapy, the patient experienced no significant adverse reactions. Following treatment, urinary obstruction symptoms markedly improved. Follow-up abdominal and urinary tract ultrasound examinations at 1week, 1month, and 4months post-radiotherapy showed marked tumor regression with no signs of recurrence. This report aims to share the treatment experience of this case, hoping to provide insights for clinicians.