Our Specialists for Medulloblastoma
Medulloblastoma care is a team sport: it starts with a delicate surgery at the base of the brain, continues through radiation to the brain and spine, and finishes with months of chemotherapy. Our neurosurgeons work side-by-side with pediatric and adult neuro-oncology, radiation oncology, and neuropathology to give you one coordinated plan.
Dr. DiPatri has been performing pediatric neurosurgery for over 27 years. He's dual board-certified in both neurological surgery and pediatric neurological surgery, and he's Chief of Pediatric Neurosurgery for the Chicagoland Children's Health Alliance, meaning he oversees pediatric brain care across Comer, Advocate, and Endeavor Health. He came to UChicago after 22 years at Lurie Children's Hospital, with additional fellowship training at Boston Children's Hospital. Dr. DiPatri is a fellowship-trained pediatric neurosurgeon with more than two decades of experience operating on posterior fossa tumors in children, and he is the surgeon who most often performs medulloblastoma resections at Comer Children's Hospital. His approach emphasizes maximal safe resection — protecting the brainstem and cranial nerves even at the cost of leaving small residual tumor — in line with current evidence that near-total and gross-total resection yield equivalent survival once molecular subgroup is taken into account.
Dr. Yamini is a brain tumor surgeon and scientist who serves as Vice Chair for Academic Affairs and Director of Neurosurgical Oncology at UChicago. In the operating room, he uses advanced imaging and navigation tools for stereotactic biopsy, laser ablation, and image-guided maximal resection. In his lab, he runs NIH-funded research into why some tumors resist treatment and into biodegradable nanoparticle vectors that deliver drugs directly to CNS tumors. Dr. Yamini directs neurosurgical oncology at UChicago and runs an NIH-funded laboratory developing biodegradable nanoparticle drug-delivery systems and new strategies to overcome chemoradiation resistance in malignant brain tumors. For adolescents and adults with medulloblastoma, he integrates surgery with our neuro-oncology and radiation oncology teams and helps connect appropriate patients to clinical trials of targeted therapies.
Dr. Warnke is an international leader in functional neurosurgery and has performed over 6,000 stereotactic surgeries and more than 3,000 brain tumor surgeries. He is only the second neurosurgeon worldwide to perform laser hemispherotomy, and he has completed over 400 laser ablation surgeries since arriving at UChicago. He is funded by four NIH grants including the BRAIN Initiative, and he directs the NAUTILUS trial for thalamic stimulation in drug-resistant epilepsy. For small recurrences or residual nodules of medulloblastoma that are not good candidates for repeat craniotomy, Dr. Warnke uses stereotactic laser ablation and frame-based stereotactic techniques — minimally invasive approaches he has performed many hundreds of times at UChicago and that can treat deep-seated lesions through a single small incision.
What Is Medulloblastoma?
Medulloblastoma is a fast-growing tumor that starts in the cerebellum — the walnut-shaped part of the brain at the back of your skull that controls balance, coordination, and fine movement. It sits in a crowded space called the posterior fossa, just above the brainstem and next to the fourth ventricle, which is one of the brain's fluid-filled chambers.
It's the most common malignant brain tumor in children, making up about 20% of pediatric brain cancers. It peaks between ages 3 and 8 but can appear in infants, teenagers, and adults. When it shows up in adults — usually in their 20s or 30s — it's rare (about 1% of adult brain tumors) and tends to behave a bit differently than in children.
Because of where it grows, medulloblastoma often blocks the normal circulation of cerebrospinal fluid, causing pressure to build up inside the skull. That's why the first symptoms are usually morning headaches, vomiting, and trouble with balance. It can also shed cells into the spinal fluid and spread along the surface of the brain and spinal cord, which is why treatment has to cover the entire central nervous system, not just the original tumor.
The good news: medulloblastoma is one of the true success stories of pediatric oncology. Five decades of clinical trials have transformed it from a nearly uniformly fatal disease into one that is cured in most children with average-risk disease.
At a Glance
- Medulloblastoma is the most common malignant brain tumor in children and also occurs, more rarely, in adults
- It grows in the cerebellum at the back of the brain and often blocks the flow of spinal fluid, causing headaches and vomiting
- Treatment almost always involves surgery, craniospinal (brain and spine) radiation, and several months of chemotherapy
- Modern pathology now divides medulloblastoma into four molecular subgroups — WNT, SHH, Group 3, and Group 4 — each with a different outlook
- With modern risk-adapted therapy, more than 80% of children with average-risk disease are alive and disease-free five years after diagnosis
Have imaging or a diagnosis already?
We'll have a specialist review your MRI and records — often within 24 hours.
What Does It Feel Like?
Because medulloblastoma almost always grows in the back of the brain and presses on the flow of spinal fluid, the early symptoms are similar in most patients. They tend to come on over weeks — not days — and get steadily worse.
Signs of rising pressure in the brain
- Morning headaches that improve after getting up and moving around
- Vomiting, especially first thing in the morning, often without nausea beforehand
- Unusual sleepiness or fatigue
- In infants: a head that's growing faster than expected, a bulging soft spot, or irritability
Signs the cerebellum is affected
- Clumsiness or a wide, unsteady walk that looks like your child is drunk
- Trouble with handwriting, reaching for objects, or climbing stairs
- Slurred or jerky speech
- Uncontrolled, rhythmic eye movements (nystagmus)
Signs of brainstem involvement
- Double vision or a new eye turn
- Tilting the head to one side to ease discomfort
- Trouble swallowing or a weak voice
These symptoms can be caused by many benign things, but if they last more than a couple of weeks — or if a child has morning vomiting plus any trouble with balance — an MRI is the right next step.
How Is It Diagnosed?
The workup for medulloblastoma happens quickly, usually over a few days, because rising pressure in the brain needs prompt attention.
Imaging
The first test is almost always an MRI of the brain with contrast. Medulloblastoma typically shows up as a bright mass in the middle of the cerebellum, often pushing on or filling the fourth ventricle. Because the tumor can seed through spinal fluid, your team will also get an MRI of the entire spine before or shortly after surgery — this is essential for staging.
Spinal fluid sampling
About 10 to 14 days after surgery, a lumbar puncture (spinal tap) is done to check whether tumor cells have spread into the cerebrospinal fluid. Waiting two weeks matters: doing the tap too soon after surgery can give a false positive because of blood and debris in the fluid.
Pathology and molecular testing
Once a sample of tumor is removed at surgery, a neuropathologist confirms the diagnosis under the microscope. But today, molecular profiling is what really drives treatment. The 2021 WHO classification of brain tumors requires assigning every medulloblastoma to one of four molecular subgroups — WNT, SHH, Group 3, or Group 4 — using DNA methylation arrays, targeted sequencing, and immunohistochemistry. Within each group, further DNA findings (like TP53 mutations in SHH, or MYC amplification in Group 3) sharpen the prognosis even more.
Your team will also check for metastatic disease on the pre-operative MRI and lumbar puncture results. The combination of how much tumor was removed, whether there is spread, and the molecular subgroup determines whether you are classified as average-risk or high-risk — and that's what dictates how intensive the treatment will be.
Types of Medulloblastoma
Medulloblastoma is not one disease — it's four. In 2012, an international consensus recognized that what pathologists had been calling one tumor was actually four biologically distinct diseases with different origins, different natural histories, and different responses to treatment. Today, every medulloblastoma is classified into one of these molecular subgroups, and it's one of the most important things to know about your or your child's tumor.
WNT-activated (about 10% of cases)
These tumors carry mutations in the WNT signaling pathway (usually in the CTNNB1 gene). They almost always occur in older children and teenagers, are rarely metastatic, and have an excellent prognosis — more than 95% of patients are cured with standard therapy. WNT tumors are so favorable that current clinical trials are testing whether radiation and chemotherapy can be safely reduced in these children to minimize long-term side effects.
SHH-activated (about 30% of cases)
These tumors are driven by the sonic hedgehog signaling pathway, often through mutations in PTCH1, SMO, SUFU, or amplification of MYCN. They show up in two peaks: infants under 3 years old and adults. The outlook depends heavily on whether the tumor has a TP53 mutation. SHH tumors with intact ("wild-type") TP53 do well — around 80% five-year survival. SHH tumors with TP53 mutations are much more aggressive, with five-year survival closer to 40%.
Group 3 (about 25% of cases)
Group 3 is the most aggressive subgroup. It occurs mostly in infants and young children, often presents with metastatic disease at diagnosis, and is strongly associated with MYC amplification and a poor prognosis. Five-year survival ranges from about 40% to 60%, and children with MYC-amplified Group 3 tumors have historically had the worst outcomes of any subgroup.
Group 4 (about 35% of cases)
Group 4 is the most common subgroup but the least well understood biologically. It affects children of all ages and young adults, often shows an isochromosome 17q on genetic testing, and has an intermediate prognosis — roughly 75% five-year survival overall, though metastatic Group 4 tumors do significantly worse. Ongoing research is now subdividing Group 3 and Group 4 into further subtypes that may refine how we treat them.
How Is It Treated?
Surgery comes first
The first step is always an operation to remove as much tumor as safely possible. Because medulloblastoma sits right next to the brainstem and fourth ventricle, this is one of the most delicate operations in all of neurosurgery. Your surgeon approaches the tumor through a small opening at the back of the skull and works millimeter by millimeter, using the operating microscope, intraoperative neuromonitoring, and image guidance to protect the brainstem and cranial nerves.
For decades, the dogma was that every last piece of tumor had to come out. A landmark 2016 analysis of 787 patients changed that thinking: once you account for molecular subgroup, the survival difference between gross total resection (no visible tumor left) and near-total resection (less than 1.5 cm² left) disappears. Today, the goal is maximal safe resection — we stop short of chasing small amounts of tumor that are stuck to the brainstem, because the neurologic cost isn't worth a benefit we can't measure.
Cerebellar mutism syndrome — what you should know
One of the most feared complications of posterior fossa surgery is cerebellar mutism syndrome (sometimes called posterior fossa syndrome). In the first few days after surgery, children who were talking normally before the operation can suddenly stop speaking, become emotionally fragile, and develop difficulty swallowing and moving. It happens to about 1 in 4 children after medulloblastoma surgery and is more common with larger tumors that invade the brainstem. Speech usually returns over weeks to months, though some children have lasting problems with speech and coordination. This is one of the reasons experience matters so much: surgical approach and judgment can reduce (though not eliminate) the risk.
Radiation therapy
After surgery, nearly all children 3 years and older receive craniospinal irradiation — radiation to the entire brain and spine — followed by a focused boost to where the tumor was. Because medulloblastoma can seed through spinal fluid, treating only the original tumor site is not enough. Dose depends on risk group: 23.4 Gy craniospinal for average-risk disease, 36 Gy for high-risk, followed by a tumor-bed boost to around 54 Gy.
Proton beam therapy, when available, is the preferred technique for children. Because protons deposit most of their energy at a precise depth and then stop, they spare the heart, thyroid, inner ears, and the rest of the body from the radiation "exit dose" that conventional photon radiation produces. The Massachusetts General Hospital phase 2 trial led by Torunn Yock showed that proton craniospinal irradiation gives the same disease control as photons with significantly less toxicity to hearing, hormones, and IQ over 7 years of follow-up.
Chemotherapy
After radiation — or, in infants, instead of radiation — patients receive about nine months to a year of chemotherapy. The standard backbone in children is a combination of cisplatin, lomustine (CCNU) or cyclophosphamide, and vincristine, based on the Children's Oncology Group trial A9961. For infants under 3, the goal is to delay or avoid radiation altogether to protect the developing brain, sometimes using intensive chemotherapy with stem-cell rescue.
Treatment in adults
Adult medulloblastoma is rare enough that most adult cancer centers rarely see it, and the evidence base is thinner. Adults generally tolerate craniospinal radiation less well than children but cope better with chemotherapy. Current practice borrows heavily from pediatric protocols, with a preference for proton radiation when feasible. If you are an adult with medulloblastoma, being treated at a center that sees multiple cases a year — with both neuro-oncology and radiation oncology experience — is especially important.
If the tumor comes back
Recurrence is usually harder to cure than a new diagnosis and is treated case by case. Options include additional surgery, re-irradiation (often with proton therapy or stereotactic techniques), high-dose chemotherapy with stem-cell rescue, and — increasingly — enrollment in clinical trials of targeted therapies aimed at specific molecular drivers like the SHH pathway.
Considering surgery or planning a second opinion?
Our multidisciplinary team reviews complex cases together. You'll get a coordinated plan, not one opinion.
What Are the Outcomes?
Medulloblastoma outcomes depend far more on molecular subgroup and risk stratification than on any other single factor. The numbers below come from the large international trials — including the St. Jude SJMB03 trial, COG A9961, and COG ACNS0331 — that define today's standard of care. Results in adults are broadly similar for favorable subgroups but somewhat worse on average because of higher rates of SHH-TP53-mutant disease and a lower tolerance for intensive therapy.
| Subgroup / Risk | 5-Year EFS | 5-Year OS | What to know |
|---|---|---|---|
| WNT-activated | ~90% | ~95% | Excellent; trials now testing reduced therapy |
| SHH, TP53 wild-type | ~75% | ~80% | Favorable; better in infants than in adults |
| SHH, TP53-mutant | ~30% | ~40% | Aggressive; often needs intensified therapy |
| Group 3 (non-MYC-amplified) | ~60% | ~70% | Intermediate outlook |
| Group 3, MYC-amplified | ~30% | ~40% | Highest-risk subgroup |
| Group 4 | ~75% | ~80% | Intermediate; metastatic cases fare worse |
| Average-risk (overall) | ~83% | ~87% | From SJMB03 and A9961 trials |
Survival is only part of the story. Because radiation and chemotherapy are being given to a growing brain, long-term side effects matter enormously. Children treated for medulloblastoma are at risk for hearing loss, hormone deficiencies, cognitive changes, and — much more rarely — second cancers decades later. That's why modern trials are focused as much on reducing therapy for favorable subgroups as on intensifying it for high-risk disease, and why proton therapy and risk-adapted chemotherapy have become standard where available.
The single most important thing a family can control is choosing a team that treats medulloblastoma often, plans every step in a combined neurosurgery-oncology-radiation-pathology conference, and has the infrastructure to deliver modern risk-adapted care — including access to proton therapy and clinical trials when appropriate.
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Have Questions About Medulloblastoma?
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