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What is choroid plexus tumors?
Choroid plexus tumors begin in the choroid plexus, the delicate, frond-like tissue inside the fluid-filled spaces of the brain (the ventricles) that produces cerebrospinal fluid — the clear liquid that cushions the brain and spinal cord. These tumors are rare and occur most often in infants and young children, though they can appear in adults. Because they grow inside the ventricles and the choroid plexus normally makes fluid, these tumors can cause too much fluid to build up, raising pressure inside the head. In babies this can make the head grow too quickly, while older children may have headaches, nausea and vomiting, sleepiness, or balance problems. There are three main forms that differ greatly in behavior: a benign papilloma, a borderline atypical papilloma, and a cancerous carcinoma. The papilloma is the most common and, once fully removed by surgery, is usually cured. The carcinoma is far more aggressive, can spread through the cerebrospinal fluid, and needs additional treatment. Because most patients are very young children whose brains are still developing, the central challenge is to cure the tumor while protecting long-term thinking, growth, and quality of life — which makes the choice and precision of treatment especially important.
The main types
Doctors group choroid plexus tumors by where it starts and how it behaves:
| Type | What it means, simply |
|---|---|
| Choroid plexus papilloma (WHO grade 1) | The most common and least aggressive form; benign and usually cured by surgery alone when completely removed, often needing no further treatment. |
| Atypical choroid plexus papilloma (WHO grade 2) | A borderline tumor with more active-looking cells; usually treated with surgery, with close monitoring and sometimes additional therapy if it returns. |
| Choroid plexus carcinoma (WHO grade 3) | The cancerous, fast-growing form that can spread through the spinal fluid; needs surgery plus chemotherapy and, in older children, radiation. Often linked to an inherited cancer-risk syndrome, so genetic counseling is recommended. |
Staging, in plain terms
Choroid plexus tumors are not staged with the TNM number system used for many adult cancers. What matters most is the tumor's grade — how aggressive it looks under the microscope — and whether it has spread through the cerebrospinal fluid to other parts of the brain or spine. Doctors determine the grade after surgery when a pathologist examines the tumor. They also check for spread with an MRI of the entire brain and spine and, when needed, a sample of the spinal fluid, because the aggressive carcinoma form can seed cells that travel in the fluid. Two other things strongly shape the plan: how completely the surgeon was able to remove the tumor, and the child's age, since very young children are especially vulnerable to the long-term effects of radiation. A benign papilloma that is fully removed generally needs no further treatment, while a carcinoma — particularly one that has spread or could not be completely removed — needs intensive combined treatment. Because the carcinoma is often linked to an inherited cancer-predisposition syndrome, genetic testing and counseling are an important part of the evaluation.
| Tumor grade (WHO 1–3) plus whether it has spread through the spinal fluid — not TNM | What it generally means |
|---|---|
| Localized papilloma (grade 1), fully removed | A benign tumor confined to where it started and completely removed by surgery; usually cured with no further treatment, just regular imaging to confirm it stays away. |
| Atypical papilloma (grade 2) | A borderline tumor; treated with surgery and watched closely, with additional therapy considered if it cannot be fully removed or comes back. |
| Carcinoma (grade 3), localized | An aggressive tumor that has not spread; treated with surgery to remove as much as possible plus chemotherapy, with radiation added for children old enough to receive it safely. |
| Carcinoma with spread through the spinal fluid | An aggressive tumor that has seeded the brain or spine; treated most intensively with surgery, chemotherapy, and radiation directed to the affected areas or the whole brain and spine in older children. |
The standard of care
Choroid Plexus Tumors is almost always treated by a team that may include a surgeon, a medical oncologist, and a radiation oncologist, combining therapies for the best result. The usual building blocks are:
Surgery
The first and most important treatment; removing the entire tumor often cures a papilloma and is the foundation of treatment for a carcinoma. Surgery also relieves the fluid buildup and pressure inside the head.
Chemotherapy
Used mainly for the carcinoma form to shrink tumor, treat any spread, and — in the youngest children — delay or reduce the need for radiation while the brain matures.
Radiation therapy
Used for the carcinoma, especially in children old enough to receive it safely; it may target the tumor area or, if the cancer has spread through the fluid, the whole brain and spine.
Managing fluid buildup
Because these tumors disturb the brain's fluid, a temporary drain or a permanent shunt may be needed to relieve pressure and protect the brain.
Genetic counseling and survivorship
Because the carcinoma is often linked to an inherited cancer-risk syndrome, families are offered genetic testing; long-term follow-up supports learning, growth, hormones, and emotional health.
How radiation treatment works
Radiation therapy uses precisely aimed high-energy beams to damage the DNA inside tumor cells so they can no longer grow and divide. For choroid plexus tumors, radiation's role depends entirely on which type a child has. A benign papilloma that is fully removed usually needs no radiation at all. The aggressive carcinoma is a different story: even after surgery and chemotherapy, radiation is often important to control the disease, particularly in children old enough to receive it safely. When the carcinoma is localized, radiation is shaped tightly around the tumor area; when it has spread through the cerebrospinal fluid, the entire brain and spine may be treated at a lower dose with a focused boost to the main site. Because most patients are very young, protecting the developing brain is a central concern. Modern planning with intensity-modulated radiation and, where available, proton therapy makes it possible to deliver an effective dose while sparing healthy tissue — protons are especially useful because the beam stops at a set depth and does not travel beyond the target. In the youngest children, doctors may delay or reduce radiation and lean on surgery and chemotherapy first, allowing the brain to mature before radiation is considered. The radiation oncologist tailors every plan to cure the cancer while protecting long-term thinking, growth, and quality of life.
The main ways radiation is delivered for choroid plexus tumors:
Focused (conformal) radiation to the tumor bed
For a localized carcinoma, radiation is shaped tightly around the area where the tumor was, delivering an effective dose while sparing as much healthy, developing brain as possible.
Craniospinal irradiation when the tumor has spread
If cells have seeded the cerebrospinal fluid, the entire brain and spinal cord are treated at a lower dose, with a focused boost to the main tumor area.
Proton therapy
Proton beams deposit their energy and then stop, so they can treat the tumor while sparing nearby healthy brain and, when treating the spine, the organs in front of it — especially valuable for protecting a young child's development.
Age-adapted, delayed, or reduced radiation
In infants and toddlers, teams may rely on surgery and chemotherapy first to postpone or limit radiation until the brain is more developed, lowering the risk of long-term effects.
Latest studies shaping care
Care keeps improving — often toward getting the same excellent results with less burden on patients. A few developments:
Radiation improves survival in choroid plexus carcinoma: Analyses of children with choroid plexus carcinoma have found that adding radiation therapy improves overall survival, supporting its use in patients old enough to receive it safely after surgery and chemotherapy.[1]
Choroid plexus carcinoma outcomes analyses
Proton therapy to protect the developing brain: Studies of proton therapy in pediatric brain tumors show it can deliver the needed dose while sparing surrounding healthy brain and tissues, with the goal of reducing long-term effects on thinking, growth, and hormones.[2]
Pediatric proton therapy reports
Genetic links guide care and family screening: Research has confirmed that choroid plexus carcinoma is frequently associated with an inherited cancer-predisposition syndrome, making genetic testing and counseling an important part of diagnosis and of protecting at-risk family members.[3]
Hereditary cancer syndrome studies
Common questions
Is my child's tumor cancer? Not always. The most common choroid plexus tumor is a benign papilloma, which is usually cured by surgery alone. The carcinoma form is cancerous and aggressive and needs additional treatment. A pathologist determines which type it is after surgery, and that answer guides the entire plan.
Will my young child need radiation? It depends on the type and the child's age. A fully removed papilloma usually needs no radiation. For the carcinoma, radiation is often important, but in infants and toddlers doctors may delay or limit it — relying on surgery and chemotherapy first — to protect the developing brain, and use proton therapy when available to spare healthy tissue.
Why is genetic testing recommended? Choroid plexus carcinoma is often linked to an inherited cancer-predisposition syndrome. Genetic counseling and testing can explain why the tumor developed, guide follow-up for the child, and identify other family members who may benefit from screening.
References
Numbered sources for the studies cited above. Links open the primary publication on PubMed or the publisher’s site.