Understanding OMS: Insights from Twelve Years of Collaborative Research
In 2013, Neuroblastoma UK joined forces with several other charities to fund the UK component of a unique international study into Opsoclonus Myoclonus Syndrome (OMS).
This study was called the UK Multicentre Study of Children with Opsoclonus Myoclonus Syndrome (UMSCOM). Analysis of this international study has provided some valuable insights into how best to treat and support children affected by this rare and complex condition.
Why Was This Study Important to Neuroblastoma UK?
The rare neurological disorder, regularly referred to as 'Dancing Eye Syndrome', is linked to neuroblastoma as around 50% of all children diagnosed with OMS also have neuroblastoma. The neurological symptoms can include rapid, jerky eye movements, muscle twitches, and problems with coordination, which are difficult to manage and can be life-changing for families.
Aims of the Study
The study aimed to build a comprehensive database, collect biological samples, test a structured treatment plan, and monitor how children’s neurological symptoms responded to treatment and changed over time.
The main aim was to find out whether the neurological symptoms had improved after standardised treatment and the passage of time. Assessments were made at one, two and five years using a standard rating scale.
How Was the Study Conducted?
The trial enrolled 101 children with OMS (more than 60% of the patients also had neuroblastoma). The UK recruited 22 participants, making it one of the top contributing countries in the trial.
The average age of the participating children was 21 months, and 63% were girls. All children received dexamethasone, a type of steroid, for three days at diagnosis and then monthly for a year.
If a child’s neurological symptoms did not improve after the first three steroid doses, cyclophosphamide, a chemotherapy medication, was added and if symptoms still persisted, they were given rituximab, an immune therapy drug, in two doses two weeks apart. The children who also had neuroblastoma received standard neuroblastoma treatment in addition.
Results and Impact
While some neurological assessments are still being completed, early findings have already helped shape current treatment. Researchers discovered that the OMS score at three and six months after diagnosis (a response to treatment score) is more useful for predicting outcomes than the score at diagnosis itself.
They also found that giving rituximab early, if symptoms didn’t respond to dexamethasone, led to improved neurological outcomes. As a result, rituximab is now recommended in the current SIOPEN treatment guidelines for OMS.
Future Impact
This study didn’t just look at treatments and outcomes, it also created a foundation for future discoveries. Neuroblastoma tissue samples collected during the trial were sent to a Tissue Bank in Newcastle for further biological studies. Researchers hope these samples will reveal clues about how and why OMS develops and why neurological recovery varies between children. A biobank in Oxford was established to store blood and cerebrospinal fluid (CSF) samples. Some of these have already been analysed and linked to clinical data, leading to the discovery of an autoantibody that could help scientists understand why patients develop OMS
What Happens Next?
It’s hoped that ongoing research based on this study will:
Identify biological markers that could help the diagnosis and treatment of OMS
Establish international agreement on the best initial, relapse, and long-term treatments
Improve cognitive and emotional outcomes for children with OMS
Understand why some children have significant long term problems following a diagnosis of OMS
Support adults who had OMS as children with continuing medical needs
Following this European OMS study, new research continues through an international registry known as POOMAS (Prognosis, Treatment, and Mechanisms in International Paediatric Onset Opsoclonus Myoclonus Ataxia Syndrome), ensuring that the progress made over the past twelve years continues to benefit children and families worldwide.
