Time to tumour detection in familial retinoblastoma patients: a retrospective study
Keywords:Retinoblastoma, Familial, Genetics, Tumour detection
Background: Screening in familial retinoblastoma through regular fundus examination and molecular genetic
testing, is recommended to improve prognosis in terms of vision, globe sparing and save life. At The Hospital for
Sick Children (SickKids) fundus screening and genetic testing is done in all patients with familial retinoblastoma,
while in Kenya there is no formalized screening protocol and genetic testing is not readily available.
Objectives: To determine the mean time to first tumour detection, tumour characteristics and outcome in
familial retinoblastoma patients seen at SickKids, Toronto, Canada and Kenyatta National Hospital (KNH),
Design: Retrospective descriptive study.
Subjects: Familial retinoblastoma patients at SickKids from July 1, 1993 to September 30, 2013, for KNH,
upto when all the medical files could be retrieved. Data collected included patient demographics, disease
characteristics, treatment course and outcomes.
Results: A total of 32 patients were reviewed; 20 (63%) were from SickKids and 12 (37%) from KNH. SickKids
patients were all bilateral (20/20, 100%), compared to 7/12 (58%) of KNH. The mean time to detection of first
tumour was 3.8 months from birth for SickKids and 25 months for KNH. Tumours were diagnosed at birth
in 13/40 (33%) of eyes at SickKids while none at KNH. At SickKids most eyes were IIRC Group A (17/34, 43%)
or Group B (15/34, 38%). None of the patients had extraocular disease. At KNH, affected eyes were at more
advanced stage: IIRC Group D (8/24, 33%) and E (4/24, 17%) with 4/24 (17% eyes) having extraocular disease. All
patients were treated using focal therapy at SickKids, (96% had laser photocoagulation). Only 2 (5%) patients
had enucleation, while at KNH, all patients had enucleation, (unilateral or bilateral); with half of them receiving
additional chemotherapy. At SickKids, 75% of salvaged eyes had vision between 20/20 and 20/60, with 8%
having vision less than 20/200. In two eyes (5%) vision was assessed as central, steady and maintained. At KNH,
62.5% of the salvaged eyes had vision reported as fixing and following light, two eyes (25%) had vision better
than 20/80. In one eye (12.5%), vision was perception of light.
Conclusion: Early diagnosis and better outcomes were observed at SickKids familial retinoblastoma compared
Recommendation: Develop a screening protocol at KNH for familial retinoblastoma through fundus examination
and genetic counseling and testing.
Castéra L, Sabbagh A, Dehainault C, Michaux D,
Mansuet-Lupo A, Patillon B, et al. MDM2 as a
modifier gene in retinoblastoma. J Natl Cancer
Inst [Internet]. 2010 Nov 4;102(23):1805–8.
Available from: https://doi.org/10.1093/jnci/
Aguirre Neto JC de, Antoneli CBG, Ribeiro KB,
Castilho MS, Novaes PERS, Chojniak MMM,
et al. Retinoblastoma in children older than 5
years of age. Pediatr Blood Cancer [Internet].
; 48(3):292–295. Available from: https://doi.
Imhof SM, Moll AC, Schouten-van Meeteren
AY. Stage of presentation and visual outcome
of patients screened for familial retinoblastoma:
nationwide registration in the Netherlands. Br J
Ophthalmol. 2006; 90(7): 875-878.
Moll AC, Imhof SM, Meeteren AY, Boers M.
At what age could screening for familial
retinoblastoma be stopped? A register based
study 1945-98. Br J Ophthalmol. 2000; 84(10):
Chang CY, Chiou TJ, Hwang B, Bai LY, Hsu WM,
Hsieh YL. Retinoblastoma in Taiwan: survival
rate and prognostic factors. Jpn J Ophthalmol.
; 50(3): 242-249.
Diciommo D, Gallie BL, Bremner R.
Retinoblastoma: the disease, gene and protein
provide critical leads to understand cancer. Semin
Cancer Biol. 2000; 10(4): 255-269.
Dimaras H, Corson TW, Cobrinik D, White A,
Zhao J, Munier FL, et al. Retinoblastoma. Nature
Reviews Disease Primers. 2015: 15021.
Leal-Leal CA, Rivera-Luna R, Flores-Rojo M,
Juarez-Echenique JC, Ordaz JC, Amador-
Zarco J. Survival in extra-orbital metastatic
retinoblastoma: treatment results. Clin Transl
Oncol. 2006; 8(1): 39-44.
Lohmann DR, Gallie BL. Retinoblastoma:
revisiting the model prototype of inherited
cancer. Am J Med Genet C Semin Med Genet.
; 129C(1): 23-28.
Linn Murphree A. Intraocular retinoblastoma: the
case for a new group classification. Ophthalmol
Clinics North Amer. 2005; 18(1): 41-53, viii.
Nyamori JM, Kimani K, Njuguna MW,
Dimaras H. The incidence and distribution of
retinoblastoma in Kenya. Br J Ophthalmol. 2012;
July 2020 Journal of Ophthalmology of Eastern Central and Southern Africa
Richter S, Vandezande K, Chen N, Zhang K,
Southern J, Anderson J, et al. Sensitive and
efficient detection of RB1 gene mutations
enhances care for families with retinoblastoma.
Am J Hum Genet. 2003; 72(2): 253-269.
Noorani HZ, Khan HN, Gallie BL, Detsky
AS. Cost comparison of molecular versus
conventional screening of relatives at risk for
retinoblastoma. Am J Hum Genet. 1996; 59(2):
He LQ, Njambi L, Nyamori JM, Nyenze EM,
Kimani K, Matende I, et al. Developing clinical
cancer genetics services in resource-limited
countries: the case of retinoblastoma in Kenya.
Public Health Genomics [Internet]. 2014;
(4):221–227. Available from: https://www.
Soliman SE, Racher H, Zhang C, MacDonald H,
Gallie BL. Genetics and molecular diagnostics
in retinoblastoma - An Update. Asia-Pacific J
Ophthalmol. 2017; 6(2):197–207.
Lohmann D, Gallie B. Retinoblastoma: Revisiting
the model prototype of inherited cancer. Am J
Med Genet C Semin Med Genet. 2004; 129C: