Radiation compromised survival of patients with heritable retinoblastoma (H1): what will be the long-term consequences of current eye salvage therapies?

Temming and colleagues (1) present important data from the German national retinoblastoma reference center (University Hospital Essen) confirming the previously observed (2) long-term very serious consequence of radiation treatment to save vision for children with heritable retinoblastoma: second cancers. The long-term overall survival of 633 patients with heritable retinoblastoma diagnosed between 1940 and 2008 was studied. Heritable retinoblastoma is initiated by constitutional mutation in the RB1 tumor suppressor gene, indicated as “H1” in the 8^th edition of the TNMH cancer staging for retinoblastoma (3). Most of the children (93%) had bilateral disease, while 7% were unilaterally affected and shown to be H1 by a close relative or genetic testing. No child with heritable unilateral retinoblastoma died as a result of a second cancer, compared to 9% of bilaterally affected patients. This may suggest that carriers of a reduced expressivity/penetrance RB1 mutation also have fewer second cancers.