Renal enlargement as presentation of isolated renal relapse in childhood leukemia

Extramedullary relapses in children with acute lymphoblastic leukemia occur most frequently in the central nervous system and in the testis. In this r eport, the authors describe a 16-year-old girl with an isolated renal relap se of acute lymphoblastic leukemia after a disease-free interval of 2 years and 8 months. This clinically inconspicuous renal relapse was suggested by a routine follow-up renal sonography. No evidence of disease was found in bone marrow or peripheral blood. Renal biopsy. was required to establish th e diagnosis. Treatment consisted of intensive chemotherapy and autologous b one marrow transplantation. The patient has been in second complete continu ous remission for 7 years. The authors recommend the use of an intensive mu ltidrug salvage regimen.