Antibody Treatment

(Here's Ethen walking; by this point he was tired.)

     After several weeks without treatment, we are now back at the hospital preparing for Ethen's first round of antibody treatment. Time at home was refreshing for everyone. Ethen gained considerable strength from the break in treatment. Just this week he took his first steps on his own (except for one step on one or two occasions several months ago). He put together a full 7 steps on his own the other night. It was a proud moment! It's difficult to come back to the hospital for treatment after such strides at home, but this is an important phase in treatment.
     As I may have mentioned before, this is the last phase of treatment. As you'll recall, phase I was comprised of chemotherapy and resection of the mass remaining after chemotherapy. Ethen had a great response to chemotherapy, and the surgeon resected all of the visible mass (three pieces of tissue). Phase II involved bone marrow transplant and radiation. The bone marrow transplant aimed to rid the blood of any cancerous cells that were stirred up during surgery, while radiation was focused on eliminating any remaining cancer cells that may have been left around the sites of the original tumor tissue. These first two phases were termed "induction" and "consolidation" treatments, respectively. This last phase of treatment is a "maintenance" treatment. It's included in the treatment protocol because of the significant increase in survival observed in patients who received this treatment during clinical trials prior to FDA approval (~20% increase in survival).
     So what does the treatment do since Ethen has no detectable disease? Because of the historically high percentage of relapse cases, there are theoretically residual neuroblastoma cells (or maybe neuroblastoma progenitor cells) in Ethen's body. Antibody treatment targets those neuroblastoma cells. This treatment is an amazing discovery and breakthrough in cancer treatment (this drug was approved by the FDA in 2015 after thirty or so years of development). The antibody drug Ethen will receive is called ch14.18, or Unituxin®. Ethen will also receive two immune system stimulants (GM-CSF and IL-2) to help his body attack neuroblastoma cells. The antibody works by adhering to a certain antigen (GD2) that is present in high concentration on the surface of neuroblastoma cells. This attachment of the antigen and antibody somehow signals immune response to the cell where ch14.18 and GD2 are paired. This leads to neuroblastoma cell death. As with many drugs, there are potential side effects. One of the common side effects is pain. This is due to the presence of this same GD2 antigen receptor on nervous system cells. Like the neuroblastoma cells, nerve cells with the antibody are attacked by the immune system, which results in significant pain for most patients.
     Please pray with us this week that we can manage Ethen's pain well. We are thankful that this phase of treatment will utilize Ethen's own immune system to attack any remaining neuroblastoma cells. Ethen's immune system is strengthening since his bone marrow transplant, but it is not at full strength. Please pray his immune system is effective at killing any residual cancer cells. Because Ethen's own body will be attacking the cancer cells, there are fewer long-term side effects to speak of; however, there can be significant short-term side effects (e.g., capillary leak syndrome, low blood pressure). Please pray his body maintains good function during antibody infusion.