Clinical and histological features of primary testicular diffuse large B-cell lymphoma: a single center experience in China

Primary testicular lymphoma (PTL) is a rare and aggressive form of extranodal lymphoma. Approximately 80-98% of PTLs are diffuse large B-cell lymphoma (PT-DLBCL). The prognosis of DLBCL patients has improved with the addition of rituximab to systemic chemotherapy, but outcomes of PT-DLBCL remain poor. This may be explained by the high rate of relapse in the central nervous system (CNS) and contralateral testis. We analyzed 1,132 newly diagnosed DLBCL patients (37 with PT-DLBCL) who were treated at our hospital between January 2009 and December 2014. Twenty-five patients finished follow-up. We analyzed clinical characteristics, response to chemotherapy, overall survival, and relapse in the CNS and contralateral testis. All patients underwent orchiectomy. The median age was 60 (range: 43-82) years. Eleven patients had stage III/IV disease. Five patients experienced CNS relapse, and three experienced relapse in the contralateral testis. Median overall survival (OS) was not reached at the time of reporting. The 3-year OS rate was 57%. None of the nine patients who received radiotherapy to the contralateral testis experienced relapse in that location. Intrathecal prophylaxis did not reduce the risk of CNS relapse. All five patients who experienced CNS relapse had the germinal center B-cell-like subtype of DLBCL.