RT Journal Article SR Electronic T1 Use of combination therapy with cisplatin and calcitriol in the treatment of Y-79 human retinoblastoma xenograft model JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 1105 OP 1108 DO 10.1136/bjo.2008.152843 VO 93 IS 8 A1 A D Kulkarni A1 P R van Ginkel A1 S R Darjatmoko A1 M J Lindstrom A1 D M Albert YR 2009 UL http://bjo.bmj.com/content/93/8/1105.abstract AB Background: Retinoblastoma is the most common primary malignant intraocular neoplasm of childhood. The poor outcomes of patients with metastatic retinoblastoma have encouraged the search for new therapies. In the current study, the efficacy of combination therapy with calcitriol and cisplatin in athymic mice with subcutaneous Y-79 human retinoblastoma tumours was assessed.Methods: 60 athymic mice were subcutaneously injected with human Y79 retinoblastoma cells. Animals were randomised into four groups: group 1, 50 μg of cisplatin; group 2, 0.05 μg of calcitriol; group 3, 0.05 μg of calcitriol and 50 μg of cisplatin; group 4, control. The cisplatin was administered once a week, and the calcitriol was given five times a week.Results: There was a significant inhibition of tumour growth in animals treated with the combination therapy of calcitriol and cisplatin as compared with controls and cisplatin alone (p = 0.0001 and p = 0.0041 respectively). In terms of toxicity, serum calcium levels were increased, but there was no mortality and minimal nephrotoxicity in any of the groups.Conclusion: The present study shows that cisplatin given in combination with calcitriol may be a viable multidrug therapy option in the treatment of high-risk retinoblastoma.