Final results of an international phase II trial of first-line treatment for primary testicular diffuse large B-cell lymphoma show that using a combined treatment strategy including chemotherapy and central nervous system and testicular prophlaxis “was associated with a good outcome.” The results were reported in the Journal of Clinical Oncology.1 Radiotherapy prevented contralateral testis relapses, but central nervous system prophylaxis “deserves further investigation,” the investigators stated.
Conducted by the International Extranodal Lymphoma Study Group (IELSG) and the Italian Lymphoma Foundation, the trial (IELSG-10) involved 53 patients, aged 22 to 79, with untreated stage I or II primary testicular diffuse large B-cell lymphoma. The treatment plan consisted of six to eight courses of R-CHOP (rituximab [Rituxan] added to cyclophosphamide, doxorubicin, vincristine, and prednisone) every 21 days (R-CHOP21), CNS prophylaxis with four doses of intrathecal methotrexate, and radiotherapy to the contralateral testis (30 Gy) for all patients and to regional lymph nodes (30 to 36 Gy) for stage II disease.
One patient experienced progressive disease at nodal and extranodal sites during treatment and died. All the others achieved a complete response. At a median follow-up of 65 months, the 5-year progression-free survival rate was 74% and overall survival rate was 85%. Nine patients relapsed; five of those patients died of lymphoma and the other four had salvage therapy. The 5-year cumulative incidence of central nervous system relapse was 6%, and no contralateral testis relapses occurred. A total of 10 patients died, none from toxicities, which were mild during the R-CHOP21 treatment. Grade 3/4 toxicities included hematologic effects (28%), neurologic effects (13%), and infections (2%).
The investigators concluded that combined treatment with R-CHOP21 plus central nervous system and testicular prophylaxis is a promising approach for primary testicular diffuse large B-cell lymphoma, achieving an effective systemic control of the disease with no contralateral testis relapses and a low incidence of central nervous system relapse. They added that the acceptable toxicity profile of treatment seen in their trial was remarkable considering that, as usual for this disease, half the patients were over age 65. ■
1. Vitolo U, et al: J Clin Oncol 29:2766-2772, 2011.