People who had hereditary retinoblastoma during childhood and did not receive high-dose radiation therapy to treat their cancer are nevertheless at an increased risk of epithelial cancers such as cancer of the esophagus, stomach, colon, lung, breast, cervix, or prostate.
Retinoblastoma is a rare childhood tumor of one or both eyes. The tumor can be sporadic or hereditary, the latter of which is associated in a mutation in the retinoblastoma 1 (RB1) gene. Compared with the general population, survivors of hereditary retinoblastoma have higher risks of early-onset second cancers, particularly sarcomas, brain tumors, and melanoma, and that risk is strongly associated with the amount of radiation received during retinoblastoma treatment. However, there is little information available about cancer risk later in life among retinoblastoma survivors--specifically, cancers that are likely not related to radiotherapy.
Olivia Fletcher and Julian Peto, of the London School of Hygiene and Tropical Medicine, and colleagues estimated the risks of the epithelial cancers that commonly occur after age 50 among 144 retinoblastoma survivors who were unlikely to have been treated with high-dose radiotherapy.
They found that very few of the cancers diagnosed within their cohort were bone or soft tissue cancers, in contrast to findings from contemporary studies in which patients are treated with radiotherapy and are more likely to have sarcomas as their second cancers. Compared with the general population, the retinoblastoma survivors were more likely to die of lung cancer, bladder cancer, and all other epithelial cancers combined.
Contact: Lindsay Wright, London School of Hygiene and Tropical Medicine, 207-927-2073, Lindsay.Wright@lshtm.ac.uk