Standard Treatment Options for Diffuse Intrinsic Pontine Gliomas (DIPGs)
While numerous clinical trials are available for children with newly diagnosed DIPGs, the utility of any therapy besides radiation therapy in the treatment of patients with newly diagnosed DIPG remains unproven.[1,2,3,4,5,6]; [7,8][Level of evidence: 2A]; [Level of evidence: 3iiiA]
Glioma is a broad category of brain and spinal cord tumors that come from glial cells, brain cells that can develop into tumors.
The symptoms, prognosis, and treatment of a malignant glioma depend on the person’s age, the exact type of tumor, and the location of the tumor within the brain. These tumors tend to grow and infiltrate into the normal brain tissue, which makes surgical removal very difficult -- or sometimes impossible -- and complicates treatment.
These brain tumors are often diagnosed...
Currently, no chemotherapeutic strategy-including neoadjuvant, concurrent, postradiation therapy, or immunotherapy-when added to radiation therapy has led to long-term survival for children with DIPGs.[10,11,12]; [Level of evidence: 2A] This includes studies utilizing high-dose, marrow-ablative chemotherapy with autologous hematopoietic stem cell rescue, which have also been ineffective in extending survival.
Standard treatment options for newly diagnosed DIPGs include the following:
Conventional treatment for children with DIPGs is radiation therapy to involved areas. The conventional dose of radiation ranges between 54 Gy and 60 Gy given locally to the primary tumor site in single daily fractions. Such treatment will result in transient benefit for most patients, but more than 90% of patients will die within 18 months of diagnosis.
Radiation-induced changes may occur a few months after the completion of radiation therapy and may mimic tumor progression. When considering the efficacy of additional treatment, care needs to be taken to separate radiation-induced change from progressive disease.
Research studies evaluating the efficacy of hyperfractionated and hypofractionated radiation therapy and radiosensitizers have not demonstrated improved outcomes using these radiation techniques.
Hyperfractionated (twice daily) radiation therapy techniques have been used to deliver a higher dose, and studies using doses as high as 78 Gy have been completed. Evidence demonstrates that these increased radiation therapy doses do not improve the duration or rate of survival for patients with DIPGs, whether given alone [1,17] or in combination with chemotherapy.
Hypofractionated radiation therapy results in survival rates comparable to conventional fractionated radiation therapy techniques, possibly with less treatment burden.[15,18][Level of evidence: 2A]
Studies evaluating the efficacy of various radiosensitizers as a means for enhancing the therapeutic effect of radiation therapy have been undertaken but to date have failed to show any significant improvement in outcome.[1,3,4,5,19,20]