Purpose The primary objective of this study was to determine whether ancillary testing for metastasis is justified in the routine examination of patients with newly diagnosed retinoblastoma. Methods The records of all patients with retinoblastoma diagnosed at the Mayo Clinic from 1952 through 1989 or examined within two months of diagnosis elsewhere were reviewed. The ancillary tests used to detect metastatic disease, available histopathologic specimens, and five-year follow-up were recorded on all patients. Results We identified 100 patients, with newly diagnosed retinoblastoma, who were ultimately followed up for at least five years after diagnosis or until death. Of the 100 patients, 35 underwent bone marrow aspiration, lumbar puncture, or both, within one month of diagnosis. Results of all ancillary tests performed in these 35 patients were negative for metastatic disease. Nine of the 35 patients had choroidal extension and two had retrolaminar involvement. Although one patient developed orbital recurrence that was successfully treated with exenteration and chemotherapy, none of the 35 patients died of metastatic retinoblastoma in a mean follow-up period of 9Vi years. The overall survival free of metastasis from retinoblastoma in these 100 patients was 97% at five years (95% confidence interval: 94% to 100%). Conclusions The routine use of bone marrow and lumbar puncture studies in the examination of all patients with newly diagnosed retinoblastoma cannot be supported by this study.