Backgound: Establishing representative cohorts of individuals treated for childhood cancer is vital to enable characterisation of the long-term effects of cancer therapies, which often only become evident many years after treatment, with growth, and the normal aging process.
Method: Of 1198 patients resident in NSW who were treated at Sydney Children’s Hospital between 1972 and 1999, and followed for at least 5 years, 1156 were shown to be alive by cross-match with the National Death Index. 70.1% were successfully traced by linkage to public data-bases or their attendance at a Long-term Follow-up Clinic. Further data was obtained from medical records, the NSW Cancer Registry, patient self-report and prospective studies.
Results: Standardised mortality and incidence ratios were 7.46 and 4.98 times higher among survivors relative to the NSW population. Causes of death included primary cancer recurrence (55%), second cancers (12%), and treatment-related complications (17%). Sixty-two percent of survivors reported at least 1 chronic late effect and 27% reported ≥3.
Studies on the survivors have guided follow-up and have prompted changes to care of new patients. Avoidance of mantle irradiation for Hodgkin’s Lymphoma has translated into significantly fewer second malignancies. Long-term morbidities in stage 4 neuroblastoma patients conditioned for autograft with TBI have resulted in protocols without TBI. Knowing that 10/12 females treated with 24Gy cranial radiation failed to lactate after delivery, assists in counselling new mothers. 11% pubertal and 11% adult survivors studied had Impaired Glucose Tolerance /Diabetes Mellitus (vs 0 and 4.9% controls, p<0.001), highlighting the importance of follow-up and lifestyle education. Documentation of persisting psychological distress in survivors, parents and siblings many years after treatment, supports intervention in all family members to prevent ongoing psychological morbidity.
Conclusions: Adult survivors of childhood cancer experience life-threatening and life-altering late effects. Knowledge of late-effects informs risk-based follow-up and modification of new treatment protocols.