<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>Retinoblastoma involving both eyes. This occurs in the majority of patients with the inherited variant. A minority of patient with bilateral retinoblastoma were found to have involvement of the pineal gland as well.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>