Figure 8. Triplets with retinoblastoma.

These triplets developed retinoblastomas in all six eyes illustrating the full expressivity and penetrance of RB1^−/− germline mutations that completely abolish pRB expression. The pedigree indicates that the three children all have the same RB1 mutation, which is not detected in their parents or older brother. The eCC^RB timelines reveal that all eyes had individualized therapy, with choices considering the overall impact on each child. Each child lost one eye, has a good-looking artificial eye and an eye with normal vision, and has disease control in less than one year. The number of eye exams under anaesthesia (EUA) was least for the child who had primary enucleation. OD, right eye; OS, left eye. Eye involvement at diagnosis is indicated in by the International Intraocular Retinoblastoma Classification;⁷⁸ the eye labelled “Group 0” had no tumour at initial diagnosis but developed a tumour 6 weeks later.