Treatment for Advanced Retinoblastoma in LMICs – The TopCAT Trial

Treatment for Retinoblastoma (Rb) includes laser therapy, freezing, and chemotherapy (intravenous and/or intra-arterial). For larger and more serious tumours, the eye is removed (enucleation), and for cancer that has metastasized elsewhere in the body, further chemo- or radiotherapy can be given.

To date however there have been very few randomised controlled trials of treatment combinations for advanced Rb to inform practice for the later stages of the disease (potentially as it is a very rare occurrence in high income countries).

A study by researchers at the International Centre for Eye Health will evaluate a new treatment regime for children with advanced Rb in Tanzania.

The study will test standard chemotherapy (intravenous vincristine, etoposide and carboplatin, or VEC) against an experimental regimen of alternating standard VEC and intravenous topotecan, intravenous cyclophosphamide and intrathecal (spinal) topotecan.

The randomised controlled trial will include 190 children in Tanzania, and the researchers will assess the effect on survival of the patients in two years after treatment, alongside adverse events.

In Tanzania currently, around 50% of Rb patients arrive for diagnosis with an advanced stage of the disease, and this is reflective of other LMICs. It is hoped that this new treatment regimen can help to improve the survival rates of children with advanced Rb, providing evidence that can prolong or save lives for many children across LMICs.

We have achieved ethics approval in London and Tanzania and are assembling a multidisciplinary team of oncologists, ophthalmologists, pharmacists, trial managers and statisticians and an electronic patient record system that is adaptable to collect trial data. We hope that not only this trial will provide evidence to improve outcomes for this specific group of children, but also provide a springboard for further trials in paediatric oncology in this region of the world where they are few and far between and where outcomes are significantly worse than in richer countries.

Acknowledgements

Our partners for the project are the Kilimanjaro Christian Medical Centre, children’s charity Tumaini la Maisha, and The National Children’s Cancer Network of Tanzania. We would like to thank Velux Stiftung for funding for this project.