Retinoblastoma Incidence in Taiwan Over a Recent 20-Year Period: A Comprehensive Nationwide Study

Hsin-Ying Lin,1 Chung-Han Ho,2,3 Yu-Shiuan Lin,1 Shu-Chun Kuo,1,4 Yi-Chen Chen,2 Yung-Jen Cheng5 1Department of Ophthalmology, Chi Mei Medical Center, Tainan, Taiwan; 2Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan; 3Department of Information Management, Southern Taiwan University of Science and Technology, Tainan, Taiwan; 4Department of Optometry, Chung Hwa University of Medical Technology, Tainan, Taiwan; 5Department of Radiation Oncology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, TaiwanCorrespondence: Yung-Jen Cheng, Department of Radiation Oncology, National Cheng Kung University Hospital, No. 138, Sheng Li Road, Tainan, 704, Taiwan, Email n052337@mail.hosp.ncku.edu.twPurpose: Continuous advancements in medical diagnostic technology and the growing availability of resources suggest a potential for fluctuations in the incidence rate of retinoblastoma (Rb). This study aimed to analyze incidence data of Rb patients in Taiwan from 1999 to 2018, utilizing the nationwide Taiwan Cancer Registry (TCR) database. Additionally, we investigated the treatment modalities used for these Rb patients and compared them with those observed in other countries.Patients and Methods: We conducted a retrospective cohort study utilizing data from the TCR database. The study cohort comprised individuals who were newly diagnosed with Rb between 1999 and 2018. The incidence of Rb was calculated as the number of patients with Rb per million live births, both for the entire population and for different gender groups and time periods. The trends in Rb incidence from 1999 to 2018 across various age groups and sexes were presented with the linear trend test.Results: From 1999 to 2018, a total of 248 cases of Rb were identified. The overall incidence rate over this 20-year period was 60.20 cases per million live births, corresponding to 1 case per 16,611 live births. Incidence rates for each 5-year period between 1999 and 2018 exhibited no significant differences. The study cohort was predominantly male, with 134 cases (54.03%) being males and 114 cases (45.97%) being females, resulting in an overall male-to-female sex ratio of 1.18. Females had lower relative risk than males (RR: 0.92, 95% CI: 0.72– 1.19). Primary surgical intervention was the preferred treatment modality for over 75% of the cases.Conclusion: This retrospective epidemiology study, using TCR from 1999 to 2018, indicated that no discernible trend of retinoblastoma incidence in Taiwan. Nevertheless, continuous monitoring of incidence rates and exploration of treatment strategies for retinoblastoma within the Taiwanese population are important to address potential changes in developing medical practices.Keywords: retinoblastoma, incidence rate, treatment outcome, Taiwan cancer registry