1. What is DIPG?
Diffuse Intrinsic Pontine Glioma (DIPG) is a malignant tumor found in the brain stem, the part of the brain that controls many vital functions. DIPG affects children of both sexes equally and is typically diagnosed in patients ages 5-9 and accounts for 10-15 percent of all childhood central nervous system (CNS) tumors. The prognosis is grim with survival beyond 12 months being rare.
2. How is DIPG Detected?
Because these tumors grow so quickly, most patients develop symptoms over a couple of weeks. Each child may experience different symptoms, but common complaints
These symptoms typically lead to a CT or MRI of the brain. MRI is usually confirmatory and further diagnostic tests or biopsy are rarely needed.
3. What Are the Treatments for DIPG?
If a child has hydrocephalus, which is only present in about 1/10 children at the time of diagnosis, then surgical treatment is needed (shunt placement or third ventriculostomy). These treatments almost immediately result in some improvement in symptoms.
The use of steroids (dexamethasone) taken by mouth are commonly started after diagnosis and result in some improvement of symptoms.
Surgical biopsy, while possible, is seldom necessary to establish a diagnosis. A biopsy is very definitive for tumor and molecular/genomic characterization. A biopsy may also be necessary for inclusion in some clinical trials. Unfortunately DIPG is not amenable to surgical removal, owing to its highly invasive growth pattern. Radiation therapy usually involves 5 weeks of outpatient treatments. This is the mainstay of treatment. Radiation therapy commonly results in improvement of the symptoms and MR appearance of the tumor. Unfortunately this benefit is only transient and tumor recurrence is the rule after several weeks to months. Thus far, no chemotherapy regimen has been able to increase survival in children. Early phase clinical trials are currently focusing on novel therapy approaches, including molecularly-targeted therapy, epigenetic/histone modification agents, and local delivery strategies, including convention enhanced delivery (CED) and intra-arterial (IA) delivery.
4. What is the Expected Outcome after Treatment for DIPG?
The prognosis for DIPG is abysmal. Median survival is about 1 year. Only 1 out of 10 children may survive past 2 years.