3.1 | Cancer Registry and Childhood Cancer Survivorship Cohort Construction
A total of 3,117 patients less than or equal to eighteen years of age at diagnosis were captured by the institutional cancer registry between January 1, 1994 and November 30, 2012. Of these patients, 2,206 were considered analytic cases in the cancer registry and included in our analysis. Based on ICCC-3 coding, 1312 were pediatric oncology patients and 894 were pediatric neuro-oncology patients, of whom 871 and 546 were seen in PHO or PNO clinic during their estimated on treatment window, respectively. For patients not seen in either clinic, a manual chart review of a 10% random sample of patients revealed that nearly all patients were either referred for transplant (hematopoietic stem cell or solid organ) after receipt of initial therapy at an outside institution or they were treated exclusively by another department (i.e. dermatology, gynecology-oncology, medical oncology or surgical oncology). For the PNO cohort, 274 patients died with or without documented relapse (30.6%) and ninety-seven (10.9%) had disease recurrence without documented death during the seven-year follow-up period, for a total of 275 PNO event-free survivors. For the PHO cohort, 312 patients died with or without documented relapse (23.4%) and 172 (13.1%) had disease recurrence without documented death during the seven-year follow-up period, for a total 590 PHO event-free survivors included in the analytic cohort (Figure 1).