A case report of primary prostate intravascular large B cell lymphoma presenting as prostatic hyperplasia.

Rational: Intravascular large B-cell lymphoma (IVLBCL) is a rare condition with a poor prognosis. The clinical presentation of primary lymphoma of the prostate is non-specific and it is difficult to distinguish from other prostatic diseases. The primary prostate IVLBCL is very rare, the diagnosis and treatment of which remains unclear. We reported a rare case to explore the diagnosis and treatment for the primary prostate IVLBCL. Patients concerns: This report described a case of a 71-year-old male diagnosed as primary prostate IVLBCL who presented with prostatic hyperplasia. Diagnosis: The patient first visited an outpatient clinic of urinary surgery because of urinary urgency and frequency and was diagnosed as benign prostatic hyperplasia in about January 2010. Four years later, the symptoms worsened quickly within two months. The diagnosis was still prostatic hyperplasia according to the physical examination and imaging. However, histopathology showed IVLBCL of prostate after transurethral resection of the prostate. Interventions: With the clear diagnosis of primary prostate stage I IVLBCL, the patient received immunochemotherapy of R-CHOP (rituximab, cyclophosphamide, adriamycin, vincristine, and prednisolone) for 4 cycles and intensity-modulated radiation therapy (IMRT) including the region of prostate with the dose of 45Gy/25f. Outcomes: The response was complete remission after all treatment. The last follow-up time of the patient was June 20th, 2019, and no evidence of disease progression was observed. The progression-free survival of the patient was about 49 months until now. Lessons: The biopsy of prostate by prostatectomy plays an important role in the diagnosis and removal of the original lesion of primary prostate lymphoma. There is no consensus on therapeutic modalities for the treatment of primary prostate IVLBCL till now. Individual treatments include immunochemotherapy and/or radiotherapy according to the National Comprehensive Cancer Network (NCCN) practice guideline of diffuse large B cell lymphoma (DLBCL) based on the performance status and tumor staging of the patient. Timely and accurate diagnosis as well as the appropriate treatment may improve the clinical outcome.