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Diffuse intrinsic pontine glioma (DIPG) represents a highly aggressive pediatric brainstem tumor characterized by diffuse infiltration of the pons, rapid neurologic decline, and markedly limited long-term survival. Tumor location renders surgical resection unsafe, leaving radiotherapy as the primary modality for temporary symptom relief. Molecular advances, including the identification of H3K27M mutations, have redefined DIPG as a diffuse midline glioma and have informed the development of emerging targeted therapies. Diagnosis relies on characteristic neuroimaging findings and clinical assessment, with management centered on stabilizing neurologic function, supporting quality of life, and integrating palliative care early in the disease course. Multidisciplinary involvement remains critical given the condition’s complexity and rapid progression. The course enhances participant understanding of DIPG pathophysiology, diagnostic workup, and current therapeutic strategies shaped by molecular discoveries. Learners strengthen competence in interpreting neuroimaging, managing evolving neurologic symptoms, and applying evidence-based approaches that support patient safety and comfort. Instruction highlights the importance of interprofessional collaboration among clinicians, neuro-oncologists, radiologists, nurses, palliative care teams, rehabilitation specialists, and psychosocial professionals. Coordinated communication among these disciplines improves prognostic understanding, supports clinical trial enrollment, streamlines care transitions, and ultimately promotes better outcomes and quality of life for affected children and their families. Objectives: Identify the early neurologic signs and imaging features suggestive of diffuse intrinsic pontine glioma. Differentiate diffuse intrinsic pontine glioma from other pediatric brainstem pathologies using clinical and radiologic criteria. Create individualized management plans that reflect symptom burden, disease stage, and family-centered goals. Coordinate interprofessional team strategies for improving care collaboration and communication to advance the care of diffuse intrinsic pontine glioma and improve patient outcomes. Access free multiple choice questions on this topic.

Diffuse intrinsic pontine glioma (DIPG) remains one of the most devastating diagnoses in the field of pediatric neurooncology. Arising within the pons, DIPG is a highly aggressive, infiltrative tumor that primarily affects children between the ages of 5 and 10.[1] Despite decades of research, the prognosis remains poor, with a median survival of less than 1 year from the time of diagnosis.[2] The deep anatomic tumor location, diffuse infiltration into vital brainstem structures, and the resistance to conventional therapies collectively contribute to its formidable clinical challenge. Initially described as a distinct clinicopathologic entity in the mid-twentieth century, DIPG is now recognized as a biologically and molecularly unique tumor subgroup within the spectrum of pediatric high-grade gliomas. In the 2021 World Health Organization (WHO) update on central nervous system tumors, DIPGs are classified as diffuse midline glioma, H3K27M mutant, highlighting their characteristic epigenetic dysregulation rather than their purely anatomic location.[3] Clinically, DIPGs present insidiously with the triad of rapidly evolving cranial nerve deficits, long tract signs, and ataxia that reflect their intrinsic involvement of pontine nuclei and adjacent fiber tracts. Magnetic resonance imaging (MRI) typically demonstrates an expanded, T2-hyperintense lesion centered in the pons with indistinct margins and minimal contrast enhancement. The mainstay of treatment is fractionated radiotherapy, which offers only transient symptom relief and minimal survival benefit. Emerging research has demonstrated the efficacy of dordaviprone, formerly known as ONC201, a dopamine receptor antagonist, in treating DIPG beyond conventional radiotherapy.[4]

The etiology of DIPG is multifactorial, encompassing aberrant neurodevelopmental processes, distinct molecular alterations, and the unique cellular microenvironment of the pediatric brainstem. Unlike adult high-grade gliomas, which are often linked to acquired genetic instability and environmental carcinogenesis, DIPG arises during normal brain development, implicating disruptions in developmental signaling pathways and epigenetic regulation as the primary drivers of tumorigenesis. DIPG arises within the ventral pons, a region undergoing active neuronal differentiation and myelination during early childhood, at the same age that the disease most commonly presents. This spatial and temporal coincidence supports the concept that DIPG originates from neural progenitor or oligodendrocyte precursor cells (OPCs) intrinsic to the developing brainstem.[5][6][7] Transcriptomic analyses support OPC-like signatures in DIPG tumors, further reinforcing their developmental cellular origin.[8] To date, no environmental or hereditary risk factors have been definitively associated with DIPG development. The tumor is not linked to prior radiation exposure, chemical carcinogens, or familial cancer predisposition syndromes such as Li-Fraumeni or neurofibromatosis.[9] This absence of known external factors suggests that DIPG arises primarily from intrinsic developmental and molecular perturbations within the brainstem.

Brainstem gliomas affect approximately 300 children in the United States each year and are the major cause of death in children with brain tumors.[10][11] The most common of these is the DIPG, comprising 80% of the fatal cases. The incidence is 1 to 2 cases per 100,000 population. DIPG has a peak incidence of 6 to 9 years of age and a slight preference for males.[1][12]

The defining etiologic event in approximately 80% of DIPGs is a mutation in the histone H3 genes, specifically a lysine-to-methionine substitution at position 27 (K27M) in H3F3A (H3.3) or HIST1H3B/C (H3.1).[13][14] This mutation disrupts the enzymatic activity of the polycomb repressive complex 2, resulting in a global loss of trimethylation of histone H3 at lysine 27 (H3K27me3) and extensive epigenetic reprogramming.[15][16][17] The resultant chromatin landscape promotes transcriptional activation of normally repressed developmental genes, maintaining cells in an undifferentiated, proliferative state.[18] Results from several studies have shown the cooccurrence of mutations in activin receptor type 1 (ACVR1) and phosphoinositide 3-kinase (PI3K) in H3.1K27M mutant tumors.[19][20][21][22] In H3.3K27M mutant tumors, mutations in the tumor suppressor 53 and platelet-derived growth factor alpha are present.[19][20] These pathways converge on dysregulated cell-cycle control, enhanced growth-factor signaling, and evasion of apoptosis. The cooperative effects of these genetic and epigenetic alterations define the core molecular landscape of DIPG. The pontine microenvironment also plays a crucial etiologic role. The pons possesses dense axonal tracts, relatively low immune surveillance, and a tightly regulated blood–brain barrier, all of which contribute to DIPG’s infiltrative nature and therapeutic resistance.[23][24] Interactions between tumor cells, astrocytes, and microglia generate a protumorigenic environment characterized by immunosuppression and paracrine support of tumor growth.

The clinical course for children with DIPG typically progresses rapidly. Most symptoms develop 4 weeks before seeking medical attention. Due to the tumor's intrinsic nature, symptoms result from dysfunction of pontine neural structures, including long tracts and cranial nerve nuclei. Diplopia is often the first sign to present and is due to an abducens nerve palsy. Dysfunction of the facial nucleus will result in facial weakness or paralysis. Long-tract signs can produce motor weakness and hyperreflexia, while dysfunction of the cerebellopontine connections will result in ataxia, dysmetria, and dysarthria. The classic triad of long-tract signs, cerebellar dysfunction, and cranial nerve palsies is present in approximately 50% of patients.[25][26] Hydrocephalus occurs in less than 10% of cases, but if left untreated, it can progress to coma and death.[27]

An MRI of the brain, with and without contrast, is the most useful diagnostic study for evaluating a patient with suspected DIPG (see Image. Diffuse Intrinsic Pontine Glioma, Magnetic Resonance Image [MRI]).[28] These tumors are expansile lesions centered within the pons and are hypointense on T1-weighted images and hyperintense on T2-weighted images.[29][30][31] Hemorrhage and edema are uncommon radiographic findings, and some degree of contrast enhancement can be seen in nearly 70% of cases, most often in a patchy pattern.[30] Restricted diffusion can occasionally be seen, although usually to a mild degree.[32] Higher values of the apparent diffuse coefficient derived from diffusion-weighted MRI images correlate with a better median survival.[33][30] MRIs of the entire spinal axis are typically recommended to exclude drop metastases.[34] In recent years, research has focused on the efficacy of liquid biopsies.[35][36] Suppose patients do not have evidence of hydrocephalus. In that case, a lumbar puncture can be performed to obtain cerebrospinal fluid for analysis to detect tumor cells and circulating tumor DNA harboring the H3K27 mutation.[37][38][39][40] Although many DIPGs can be diagnosed based on classic imaging features and clinical presentation, some cases with atypical imaging findings may require biopsy to obtain a tissue diagnosis.[41] Furthermore, biopsies enable patient enrollment in clinical trials in which tissue is used to identify molecular and genetic derangements, thereby enabling targeted therapy. While historically deferred because of the tumor location in the brainstem, stereotactic biopsies are now commonly performed in many highly specialized pediatric medical centers.[42][43][44] A study comparing microsurgical biopsies with frameless robotic-assisted stereotactic biopsies showed shorter operative time, a shorter postoperative intensive care unit stay, a lower rate of neurological impairment, and lower overall cost in patients undergoing stereotactic biopsies.[45] Several other studies have shown that stereotactic biopsies are safe and efficacious, with diagnostic yields of 90% to 100%.[46][47][48][49]

Corticosteroids, specifically dexamethasone, are often administered after diagnosis and during radiation therapy. Complications due to long-term use should be avoided; therefore, they should be tapered as quickly as tolerated by the patient.[50][51] Steroids stabilize the blood-brain barrier and can affect tissue penetration of systemic drug therapies.[52] Over the course of the disease, less than 10% of patients diagnosed with DIPGs will develop hydrocephalus, although it has been reported that up to 55% of patients can have ventriculomegaly.[53] In cases of hydrocephalus, cerebrospinal fluid diversion by ventriculoperitoneal shunting or endoscopic third ventriculostomy is often required.[53][54] Conventionally fractionated radiotherapy remains the standard of care for children with DIPGs, although hypofractionated radiotherapy has shown promising results when compared to conventional radiotherapy.[55][56][57] Radiotherapy is usually delivered at a total dose of 54 Gy over 6 weeks (1.8-Gy daily fractions). Hypofractionated radiation to a total dose of 39 Gy has similar outcomes and is better tolerated in young children.[58][59] Reirradiation for tumor progression can be considered, with mild symptoms and survival benefits.[60][61][62][63][64] Results from recent studies have shown the efficacy of Dordaviprone, a dopamine receptor antagonist, in the treatment of recurrent H3K27M-mutant diffuse midline gliomas.[4][65][66][67] This drug is now approved by the United States Food and Drug Administration for patients 1 year or older with H3K27M-mutant diffuse midline gliomas with progressive disease following prior treatment. Other novel therapies are being studied and include those listed below.[68][69] Oncolytic viruses [70][71] Chimeric antigen receptor T-cell therapy [72][73][74][75] Convection-enhanced drug delivery systems [76][77][78] Focused ultrasound [79][80] Phase 1/2 trials of the oral histone deacetylase inhibitor, vorinostat, have also been recently published.[81][82]

The prognosis of DPIG is poor due to the absence of effective therapies. This tumor is the primary cause of death among brain tumors in children. In a report from international registries, the median survival time was 11 months among 1008 patients. Long-term survivors living for more than 2 years were more commonly found to present at ages younger than 3 and older than 10, and had longer symptom duration.[2] Similar results were observed among 1183 patients, including children diagnosed before age 3, who demonstrated improved overall survival.[83] Other negative prognostic factors include extrapontine extension, contrast enhancement, larger size, necrosis, and metastatic disease.[30][84]

In a systematic review of 192 stereotactic biopsies, complications were reported in 13% of patients, with cranial neuropathies being the most prevalent at 4.2%. Perioperative hemorrhage (3.6%), hemiparesis (2.1%), and speech disturbances (1.6%) were also reported.[47]

The following consultations will likely be needed in patients with DPIGs: Neurooncology Radiation oncology Neuroradiology Neurosurgery Neurology Neuropathology Pediatric intensive care Early consideration should be given to consulting advanced pediatric care or pediatric palliative care specialists. Offering palliative care services to all patients with DIPG early in the course of the disease provides support for the immediate and ongoing physical, psychological, and social effects that this lethal disease will have on the patient and the family. Combined neurooncologic and palliative care support will influence how patients and their families function during treatment and can even help identify disease-related changes before clinically or radiographically suspected progression.[85]

Deterrence in DIPG is limited because the disease stems from non-modifiable molecular changes within the brainstem, leaving no viable preventive strategies or modifiable risk factors. As a result, the clinical focus centers on early recognition of progressive neurologic symptoms—such as cranial nerve palsies, gait instability, dysphagia, or rapid functional decline—to ensure timely imaging, diagnosis, and initiation of symptom-directed management. Patient and family education, therefore, becomes essential in optimizing outcomes and supporting informed decision-making. Families must receive clear, compassionate explanations of the disease process, prognosis, expected treatment responses, and the realistic limitations of radiation, corticosteroids, and clinical trial therapies. The timeline of diagnosis significantly influences how families emotionally process the situation, underscoring the importance of involving psychologists, psychiatrists, and family therapists in comprehensive care. Education should also prepare caregivers for the functional changes that accompany disease progression and treatment. This includes understanding the development of neurologic deficits and physical impairments, and learning practical skills required for home-based care, such as nasogastric feeding, Foley catheter management, prevention of sacral decubitus ulcers, and the challenges associated with becoming bedridden. Thorough instruction on these aspects empowers families, enhances safety, and reduces preventable complications. By integrating early recognition, realistic education, psychosocial support, and hands-on caregiver training, clinicians can improve patient-centered care, support families through the trajectory of DIPG, and maintain dignity and comfort throughout the disease course.

Interprofessional management of DIPG requires highly coordinated, patient-centered collaboration due to the tumor’s aggressive biology, limited therapeutic options, and the profound emotional and functional impact on patients and families. Physicians and advanced practitioners lead diagnostic clarification, communicate prognosis with clarity and compassion, and coordinate multimodal therapies such as radiation, targeted agents in clinical trials, and symptom-directed care. Nurses provide continuous assessment of neurologic function, manage treatment-related toxicities, and reinforce education to families, ensuring early recognition of complications. Pharmacists optimize dosing, review potential toxicities, and monitor interactions between chemotherapy, targeted therapies, corticosteroids, and supportive medications—critical for maintaining safety in a population highly vulnerable to adverse events. Rehabilitation specialists, social workers, child-life experts, and palliative care teams contribute essential support by addressing functional decline, cognitive changes, psychosocial stressors, and quality-of-life priorities. Effective team strategy relies on structured communication—such as tumor board reviews, daily care huddles, and unified care plans—to align goals, anticipate complications, and ensure seamless transitions between outpatient, inpatient, and home-based care. Clear documentation of steroid weaning plans, neuroprotective strategies, and management of symptoms such as dysphagia, cranial nerve deficits, and airway compromise enhances safety and reduces variability. The team prioritizes shared decision-making with families, highlighting realistic outcomes, integrating palliative principles early, and offering access to clinical trials when appropriate. By synchronizing roles and maintaining open, anticipatory communication, the interprofessional team enhances patient safety, supports families through complex decisions, and maximizes functional outcomes and quality of life despite the disease’s poor prognosis.