Mailgnant Lymphoma Involving the Prostate: A Case Report

Malignant lymphoma of the prostate gland, either primary or secondary, is rare. We report a 74-year-old male who was diagnosed with disseminated lymphoma including involvement of the prostate gland with the initial presentation of urinary retention. Digital rectal examination revealed mildly enlarged prostate gland with smooth and rubbery consistency. He received transurethral resection of the prostate under the impression of benign prostatic hyperplasia. The pathology found diffused infiltration of atypical lymphoid cells infiltration. The immunohistochemical staining revealed positive for CD20, and consistent with malignant B cell lymphoma. Systemic work-up found that his disease has disseminated many areas. Back mass biopsy showed small to medium atypical lymphoid cells diffused infiltration with immunohistochemical staining for CD3(-), CD5(-), CD10(+), CD20(+), CD23(-), and Cyclin D1(-). The diagnosis of follicular lymphoma was made. The patient received four cycles of chemotherapy with rituximab, cyclophosphamide, etoposide, vincristine and prednisone (R-CEOP). After temporarily partial response, tumor regrowing was noted. Salvage chemotherapy followed by the radiotherapy (RT) to the enlarged paraaortic lymph nodes was given. The patient did not finish the RT course because of exacerbated condition. He died with the disease 9 months after diagnosis.