Registration and classification of adolescent and young adult cancer cases.

Cancer registries are an important research resource that facilitate the study of etiology, tumor biology, patterns of delayed diagnosis and health planning needs. When outcome data are included, registries can track secular changes in survival related to improvements in early detection or treatment. The surveillance, epidemiology, and end results (SEER) registry has been used to identify major gaps in survival for older adolescent and young adult (AYA) patients compared with younger children and older adults. In order to determine the reasons for this gap, the complete registration and accurate classification of AYA malignancies is necessary. There are inconsistencies in defining the age limits for AYAs although the Adolescent and Young Adult Oncology Progress Review Group proposed a definition of ages 15 through 39 years. The central registration and classification issues for AYAs are case-finding, defining common data elements (CDE) collected across different registries and the diagnostic classification of these malignancies. Goals to achieve by 2010 include extending and validating current diagnostic classification schemes and expanding the CDE to support AYA oncology research, including the collection of tracking information to assess long-term outcomes. These efforts will advance preventive, etiologic, therapeutic, and health services-related research for this understudied age group.