The occurrence of de novo cancer in renal transplant patients who have received immunosuppressive therapy has been noted. An increased incidence of second primary neoplasm (SPN) has been reported in adults with various forms of cancer. The incidence of SPN in childhood cancer is lower. Successful therapy in several childhood cancers has resulted in prolonged disease-free survival time with the opportunity for longer patient-years of observation. The development of a SPN, an astrocytoma, in a child with acute lymphocytic leukemia who remained in continuous complete remission for more than 6 years is reported. The incidence of SPN in childhood cancer needs to be established.