[Long-term complete remission of HIV-negative primary testicular plasmablastic lymphoma treated with bortezomib in combination with EPOCH].

Plasmablastic lymphoma (PBL) is a rare variant of diffuse large B-cell lymphoma that is frequently associated with HIV infection or other immunodeficiencies. We present a case of HIV-negative primary testicular PBL with long-term complete remission (CR) and successful treatment with bortezomib in combination with EPOCH (V-EPOCH). Because of rapidly increasing right testicular swelling, an 86-year-old man without immunodeficiencies was admitted to our hospital. Following that, a right high orchiectomy was performed. Histopathological and immunohistochemical analyses revealed diffuse infiltration of plasmablastic lymphocytes, which were positive for CD38, CD138, CD56, MUM1, lambda, EBER, and MYC respectively, but negative for CD20. The MIB-1 index was 90%. FDG abnormal uptake was discovered on PET/CT at systemic lymph nodes. There was no abnormal cell infiltration in either the bone marrow or cerebral spinal fluid. He was diagnosed with PBL, clinical-stage IIIE-A, IPI high-intermediate risk. He achieved durable CR more than 30 months after the diagnosis after six courses of V-EPOCH, followed by intrathecal prophylaxis (IT) and adjuvant radiation therapy (total 30 Gy). Although PBL shows an aggressive clinical course and poor prognosis, adequate therapeutic approaches for PBL have not been established due to the rarity of this disease. According to our findings, V-EPOCH combined with IT and adjuvant radiotherapy appeared to be feasible and effective as a frontline treatment for elderly patients with primary testicular PBL.