Friday, October 8, 2010

Opsoclonus Myoclonus Ataxia (OMA)

It's been a while since we updated everyone and that is a good thing.  Keira's most acute issue, namely her Neuroblastoma, seems to have been addressed.  Her initial pathology came back "favorable" which means that this is a malignant tumor but one that tends to remain isolated and not spread.  Her lymph node and bone marrow biopsy also don't show any signs of spreading, and there doesn't appear to be any signs of spreading from her CT, MRI, and bone scans which were done this past Wednesday.  There is one more MIBG scan that has to happen next Tuesday which is part of the standard Neuroblastoma diagnosis protocol, and this scan will be a final validation (fingers crossed) that the cancer has not spread.  

If all this is indeed the case, it is very likely that resection of the tumor will be the course of treatment for Keira's cancer,  and not require any chemotherapy.

We continue to receive tremendous support from friends and family and this is all very helpful and encouraging.  We're receiving more and more questions now of Keira's OMA syndrome and I thought I'd post some of the information so everyone can understand this neurological disorder.

It's enough for little Keira (and any child for that matter) to have endured everything she has, dealing with the loss of her fine and gross motor skills, then having been diagnosed with Neuroblastoma, and then having surgery to remove the mass.  But for Keira, we're still in the early stages of now dealing with the OMA, which is not a very well understood neurological disorder, partly because it only occurs in 1/10,000,000 children a year.  In the US, there will typically be ~10 cases of OMA that develop in a year.

OMA stands for Opsoclonus Myoclonus Ataxia Syndrome (also referred to as OMS or OMAS).  (1) Opsoclonus refers to uncontrollable, rapid, jerky eye-movements.  (2) Myoclonus refers to jerky, tremor-like movement.  (3) Ataxia refers to the loss of coordination and balance (the inability to walk).  (4) In addition to these conditions, there is also extremely varying behavioral conditions that affect sleep and mood.  Keira has 2, 3, and 4, and hopefully will not develop 1.  

OMA is thought to be triggered solely by Neuroblastomas.  What happens is that the body's immune system starts producing antibodies to combat the cancer.  Since Neuroblastomas are associated with nerve tissue, it is thought that there is some marker that is shared between normal brain/nerve tissue and the Neuroblastoma, and it is this shared marker which causes these antibodies to start attacking nervous system function (thought to be specifically in the Cerebellum, which is what controls movement and mood, and hence why OMA presents with loss of control of these functions).  

The irony here is that the very antibodies that have likely minimized the growth and spread of the Neuroblastoma, are the very culprits that causing the OMA.  In fact, if Keria didn't present with OMA symptoms, it likely would have been months before the Neuroblastoma was found.  

Now that the Neuroblastoma has been removed, it is not as if Keira's OMA symptoms will naturally get better.  This has probably been the most confusing and frustrating point for many of us to comprehend.  Keira's immune system has already been triggered to produce these antibodies, and similar to how a vaccine forces the production of antibodies which stay with you for a prolonged period of time, these antibodies and their continued production, will remain in Keira's body, and hence will continue to attack her nervous system.  

What we're now focusing on, are therapies to try and manage and control the OMA, which ultimately means that we have to manage and control these antibodies by some form of immune system suppression.  This is now actually more of a neurological auto-immune disorder than a cancer and we're shifting our focus to treat it as such.

Because there are so few cases of OMA, there is not a lot of data as to what drug therapies work and in what ways.  The goal is to find a combination of drug therapies, which will likely be a long term process, that work to combat specific symptoms of OMA by interfering with the antibodies or the systems that produce the antibodies in some way.   Keira could respond to these therapies very well, respond but do so in a remission/relapsing cycle, or only minimally respond to to these therapies.   Her motor development and cognitive abilities could be impaired, and it will likely be a while before we understand exactly how that would impact her developmental path and lifestyle.

Such an unknown prognosis is naturally very scary.  But we continue to remain hopeful and optimistic, and will be supporting and encouraging Keira as she starts these drug therapies.  The road ahead will be filled with many ups and downs, and regardless of what path she takes, we will be here to give her love and support and continue to believe in her spunk and stubbornness to keep fighting and not underestimate her will to walk and run again :)