Age and lateness of referral as determinants of extra-ocular retinoblastoma

The risk of extra-ocular (EO) vs. intra-ocular disease was evaluated in a retrospective study of 158 consecutive cases of retinoblastoma (age range: birth to 113 months) admitted to the A.C. Camargo Hospital, Brazil, between January 1975 and December 1985. The risk of having EO disease was strongly dependent on the age at diagnosis and lateness of referral. The older the child at first admission the higher the risk of finding EO disease at diagnosis. This association was considerably more pronounced among sporadic unilateral cases. Patients with a history of longer duration of symptoms were more likely to exhibit EO disease than patients seeking medical attention within six months of the onset of the disease. This association seemed to be confounded by the genetic form of the disease as the increase in risk of EO disease appeared later among the germinal cases. Clinical stage and lateness of referral were the variables most associated with the survival experience of patients.