The purpose of this observational research study is to follow participants who have been treated with either bel-sar or received alternate treatment (sham, standard of care therapy, etc.) while participating in a previous Aura Biosciences clinical research study to assess the long-term safety and effectiveness in these subjects. This study will collect information from procedures conducted as part of routine follow-up eye care and cancer care. Additionally, the registry will collect all adverse events, information about pregnancy and symptomatic overdose.