What is Diffuse Intrinsic Pontine Glioma?
Your child’s doctor can give the full, medical description of diffuse intrinsic pontine glioma (DIPG), all of the treatments that are available, and your child’s overall prognosis. This guide is designed to provide high-level introductions to these areas to assist with the decisions that you will be making along with your doctor.
Simply put, DIPG is a cancer of the pons – the area directly above the brainstem – and is considered one of the most dreaded forms of childhood cancer due to the historically poor prognosis. DIPG is very rare and affects approximately 300 children per year in the United States. There is no known cause; it affects girls and boys equally; spans all social, racial, and religious groups; and has a peak incidence around 6 to 9 years of age.
Cancerous tumors are classified and named based on their pathology and location. This tumor is diffusely spread throughout the pons and initially forms in the glial cells that support the central nervous system. DIPG is also called diffuse pontine glioma, diffusely infiltrative brainstem glioma, and brainstem glioma. The Marc Jr Foundation, and most of the organizations that we collaborate with use the name diffuse intrinsic pontine glioma (DIPG).
Having your child diagnosed with DIPG is earth shattering. Everything in your life has been reprioritized. When it comes to the health of your child, you know them better than anyone else in the world including your doctor. Trust your judgment, ask questions, and don’t be afraid to seek second opinions.
Survival times vary from child to child with the majority of children dying within one year of diagnosis. Fewer than ten percent of children survive for more than two years.
The initial symptoms of DIPG build gradually for as much as six months prior to diagnosis and include clumsiness, weakness of an arm and/or leg, double vision, tilting of the head, mood changes, and headaches. The gradual buildup of the severity of these symptoms allows them to go unnoticed for months.
Treatment plans for DIPG are usually designed to relieve the symptoms of the cancer as well as reduce the size and growth rate of the tumor.
Radiation or Radiotherapy
Radiation is the primary treatment plan for most children as it has shown positive results in reducing the size of tumor. Radiation therapy is given in low doses over approximately six weeks to the exact portion of the brain that is affected. The first few sessions are used to create a targeting mask for the treatments and will include another CAT scan or MRI. Your child will wear the mask during subsequent treatments to ensure that the radiation is being delivered to the correct portion of the brain to maximize the effectiveness. Common side effects of radiation include decreased energy and hair loss to the radiated areas.
Chemotherapy and other cancer fighting drugs are constantly being evaluated for use in treating DIPG. Traditionally, chemotherapy has shown little impact on the treatment of DIPG due to the blood brain barrier that protects the brain from infections. Improvements have been made in recent years, but to date there is no commonly accepted chemotherapy plan for DIPG. Many of these newer treatment plans are designed to increase the effectiveness of radiation therapy. Your doctor will present you with information on any of these programs that are currently available. We recommend reviewing page 87 of the Moss Report for details on how clinical trials are designed and operated as well as asking your doctor for details on the side effects of the treatment, how the drugs are administered, and what the expected outcomes are.
Decadron (Dexamethasone) is a very powerful steroid commonly prescribed to reduce the swelling of the tumor and relieve many of the initial symptoms associated with DIPG. Most children are slowly weaned off if it during or after radiation. Many doctors prescribe it as part of palliative care as well due to the speed at which it can relieve swelling and the accompanying symptoms. Side effects include decreased energy, sleeplessness, irritable mood changes, food cravings, weight gain, puffiness of the face, high blood pressure, and an increased risk of infection. We recommend patience and love when dealing with your child while they are taking Decadron.
Surgery is not a common option for DIPG due to the way that the cancer diffusely grows between the normal cells of brain. Surgery can be used to place shunts into the brain to relieve pressure, but this is uncommon.
In addition to the standard therapies, there may be new/experimental therapies available for your child. These treatments are considered experimental because they have not been given to many children and we do not know if they are going to be helpful in the treatment of DIPG. These treatments may be available through participation in a clinical trial or study. If you are interested in possible alternative treatments, you should ask your doctor to see what options may be available for you. Important questions to consider asking in addition to what trials are available: What are the risks and side effects? Has this trial shown any effectiveness in DIPGs? Is there a reason it should be tried in DIPGs? How often do we have to be in the clinic for this study? You can also visit www.clinicaltrials.gov for additional information.
Progression after Treatment
Most children experience a relief from the symptoms of DIPG after radiation treatment. This “honeymoon” period can last for weeks or months as each child’s tumor, responsiveness to radiation and treatments, and general health are different. We recommend using this time to enjoy your child and explore any additional treatment options that may be available.
Unfortunately, most children will experience a recurrence of the tumor and a return of their symptoms. For most, the symptoms will return at a faster rate and with greater severity than they originally appeared. We recommend focusing on palliative care – health care focused on reducing the severity of the symptoms rather than to halt or reverse their progress – and on being together as a family.
Your job as a parent is to remain focused on keeping your child feeling safe and loved. This time is no different.