TUMORES RAROS EN NIÑOS Y ADOLESCENTES RARE TUMORS IN CHILDREN AND ADOLESCENTS

SUMMARY Although perceived as rare, infrequent tumors, defined as childhood solid malignancies with an annual incidence < 2/million and not considered in other clinical trials, account for 15% of all cancers in patients younger than age 20 and for 30% of all tumors in patients ages 15 to 19. National and international cooperative projects on rare paediatric tumours have been developed to improve the clinical management and basic research on these tumors. We reviewed the process developed and the problems it had to face, as low rates of registration, low levels of participation in tumor banking, and clinical trials. This initial experience has allowed to develop alternative strategies that could help to launch a latinamerican initiative. Experience demonstrates the feasibility of a national multidisciplinary cooperation and suggests that international studies can be performed, increasing our knowledge to understand the biology and improving the treatment results of young patients with rare cancers.