Rituximab (R) chop with CNS and contralateral testis prophylaxis improves the outcome of primary testicular lymphoma (PTL): Final results of IELSG10 study

Introduction: PTL has poor prognosis with 5-yr OS of 40-55% and frequent failures in contralateral testis, CNS and extranodal sites. The prospective phase II international trial (IELSG10 and Intergruppo Italiano Linfomi) for stage I or II PTL aimed to define standard treatment for PTL. This analysis provides the final results of the study. Material and Methods: From June 2001 to December 2006, 53 pts with untreated stage I-II PTL were enrolled and treated with: standard doses RCHOP21 for 6-8 (in stage II pts with slow response) courses; intrathecal methotrexate (IT MTX) 15mg for 4 doses; 30Gy scrotal RT to the contralateral testis for all pts and 30-36Gy regional RT to lymph-nodes for stage II. Results: median age 64 (22-79); 40 and 13 stage I/II; 4 with bilateral testicular involvement; 6 LDH > normal. All received RCHOP21. Fifty received adequate CNS prophylaxis (at least 4 IT MTX); 3 less than 4 because of toxicity. Scrotal RT was given to 48 pts; 5 did not perform it (3 refusals, 1 PD and 1 bilateral orchiectomy). Fifty-two pts (98%) were in CR and 1 progressed. With a median follow-up of 42 months, 3-yr OS and 3-yr PFS were: 86% (95% CI 72-94%) and 83% (95% CI 68-91%). Eight relapsed or progressed: 2 in nodal sites, 4 in extranodal +/- nodal and 2 in CNS (1 isolated meningeal and 1 meningeal + nodal). The actuarial risk of CNS relapse at 3-yr, considering competitive risk of death, was only 2% (95% CI 0-5%). No contralateral testis relapses occurred. Nine pts died: 4 of DLBCL, 1 of colon carcinoma and 2 of AML 4 while in CR. Grade 3-4 toxicities were: leukopenia 27% and neurologic 13%. Infections were recorded in only 2 pts with no other extrahematological toxicities. No toxic deaths occurred. Conclusions: RCHOP21 with complete CNS and scrotal prophylaxis improves the outcome of PTL compared with literature data. Contralateral testis relapses were not observed and the incidence of CNS relapse was low.