Retinoblastoma is a cancer of the light-sensitive lining at the back of the eye, the retina.  It occurs in young children, usually in the first two years of life.  It is a very uncommon form of cancer with only about 40 new cases being diagnosed each year in the United Kingdom. It is equally common in boys and  girls.

In about 4 out of 10 cases the retinoblastoma is caused by a faulty gene (RB gene) which may have been passed down from a parent. Children who have this heritable form of retinoblastoma are at increased risk of developing other cancers as they grow older. Different studies over the years have given a wide range of figures for this risk so it is difficult to be sure just how likely it is that a second cancer will develop. However there is some good evidence that if radiotherapy is used as part of treatment for retinoblastoma then this makes the chance of a second cancer more likely. The sorts of cancer that can occur include bone tumours (osteosarcomas), certain types of muscle tumours (soft tissue sarcomas), brain tumours, malignant melanomas, leukaemia and lung cancer.

The risk of developing further cancers continues into adult life, but as this is well known, children who have this heritable retinoblastoma are checked regularly to pick up any other cancer at an early stage. Advice will be given on lifestyle changes which help reduce the risk of certain cancers in the future. These include avoiding smoking and using adequate sunscreen to prevent sunburn.

Children who do not have the inherited type of retinoblastoma are not at any increased risk of developing other cancers when they are older.