Retinoblastoma in Infancy with Subsequent Bladder Leiomyosarcoma in Adulthood: Genomic Considerations.

Hereditary retinoblastoma is attributed to germline mutation in an RB1 tumor suppressor gene followed by somatic mutation in the other allele. This report details a case of leiomyosarcoma of the bladder in a 24-year-old man with a history of retinoblastoma treated by enucleation and radiotherapy in infancy. Leiomyosarcoma is the most common secondary soft tissue malignancy in retinoblastoma survivors; however, leiomyosarcoma of the bladder in retinoblastoma survivors is very rare. Survivors of hereditary retinoblastoma should be monitored closely for secondary malignancies, and there should be an increased suspicion of malignancy. Furthermore, tumors can occur outside the field of radiation.