Cyclophosphamide, vincristine, and the blood testis barrier.

The blood testis barrier has been implicated in the pathogenesis of testicular relapse of childhood acute leukemia by forming a "sanctuary site" for leukemic cells. Experiments were conducted to test the transport of carbon 14 cyclophosphamide and tritiated vincristine across the blood testis barrier. Both cyclophosphamide and vincristine crossed the blood testis barrier. However, other factors such as the transport of immunoglobins and leukocytes across the blood testis barrier may interact in the pathogenesis of leukemic testicular relapse.