Transient increase in mitogen-induced lymphoproliferative responses in patients with testicular cancer after BEP chemotherapy

Objectives. To investigate the impact of polychemotherapy on cellular immun ity in patients with testicular cancer. Methods. Lymphocyte subpopulations, lymphoproliferative responses to mitoge nic stimulation, and mitogen-induced release of soluble interleukin-2 recep tor from peripheral blood mononuclear cells were investigated in 15 patient s with testicular germ cell tumors a median of 61 months (range 7 to 73) af ter polychemotherapy with bleomycin, etoposide, and cisplatin (BEP). Results. The numbers of peripheral blood T cells (CD3+), CD4+ and CD8+ subs ets, and lymphoproliferative responses to pokeweed mitogen, phytohemaggluti nin, and concanavalin A in patients were comparable to those of healthy con trol subjects. When two groups of patients were formed according to elapsed time from BEP polychemotherapy and study onset (group A, 12 months and gro up B, 69 months after termination of BEP), a significant increase in lympho proliferative response to concanavalin A (P <0.05) was found in group A 1 y ear after chemotherapy. Conclusions. BEP chemotherapy administered to patients with testicular canc er does not result in impairment of cellular immunity but rather leads to a significant increase in the capacity of patients' lymphocytes to respond t o mitogenic stimulation up to 1 year after polychemotherapy. Moreover, the increased T-cell activity found after BEP therapy may contribute to the hig h rate of long-term complete remission. UROLOGY 55: 934-938, 2000. (C) 2000 , Elsevier Science Inc.