Second primary tumors in patients with retinoblastoma. A review of the literature

Purpose: The aim of this survey was to review the different studies regarding the occurrence of second primary tumors (SPT) among survivors of retinoblastoma. Methods: Ovid (Medline, Current contents life, Psychlit, Embase) was searched for the years 1966-1995 using the mesh headings: 'retinoblastoma', 'second primary neoplasms', and 'multiple primary neoplasms'. The inclusion criteria were: the study should involve 50 patients or more and should not be limited to one specific SPT. A checklist with criteria regarding the study design and the results was applied to each study. Results: Eleven studies were identified which met the inclusion criteria. Thirty-five different types of SPT (N(total) = 243) were reported. Most of them were osteosarcomas (37.0%), followed by melanomas (7.4%), soft-tissue sarcomas (6.9%), brain tumors (4.5%), fibrosarcomas (3.3%), chondrosarcomas (3.3%), and sarcomas (3.3%). Less frequently reported were leukemias (2.4%), sebaceous cell carcinomas (1.6%), and non-Hodgkin lymphomas (1.6). Pineoblastoma, which in fact is a trilateral retinoblastoma and not an SPT, was found in 2.4%. Despite the differences, all 11 studies showed a higher incidence of SPT compared to the general population. Only 4 studies were judged to be free from selection bias, reporting a cumulative incidence of SPT of 8.4% 18 years after diagnosis, 15.7% at the age of 20 years, 19% at the age of 35 years, and a relative risk of 15.4 for SPT, respectively. Conclusion: SPT is a serious problem for the survivors of hereditary retinoblastoma and its importance shoud be recognized in (genetic) counseling of patients.