Trial results for proton beam radiotherapy in patients with brain cancer, specifically medulloblastoma and pineoblastoma, were posted on ClinicalTrials.gov on 2025-08-13. The study reported a 3-year cumulative incidence of ototoxicity of 26.0% among participants receiving proton beam radiation.
Background
Medulloblastoma and pineoblastoma are types of brain tumors that often require radiation therapy as part of their treatment. Historically, photon radiation therapy has been used for craniospinal irradiation (CSI), which targets the entire central nervous system. This study investigated proton beam radiation therapy, which studies have suggested may cause less damage to normal tissue compared to photon radiation therapy due to its distinct physical characteristics. Understanding the long-term effects of proton beam therapy on critical functions like hearing, endocrine health, and neurocognition is crucial for optimizing treatment strategies for these patient populations.
Trial design
This completed study, designated as Phase NA, enrolled 90 participants. The trial focused on individuals with Brain Tumor, Medulloblastoma, and Pineoblastoma. The intervention studied was Proton Beam Radiation, delivered as part of craniospinal irradiation. The trial aimed to examine the effects of this specific radiation type.
Key results
The trial reported several key measurements and analyses for participants who received proton beam radiation:
- Cumulative Incidence of Ototoxicity:
- The 3-year cumulative incidence was 26.0% (95% Confidence Interval: 16.0 to 37.0).
- The 5-year cumulative incidence was 27.0% (95% Confidence Interval: 17.0 to 38.0).
- Endocrine Dysfunction:
- The 3-year cumulative incidence was 46.0% (95% Confidence Interval: 34.0 to 57.0).
- The 5-year cumulative incidence was 67.0% (95% Confidence Interval: 54.0 to 77.0).
- Neurocognitive Effects:
- The mean score on a scale was 102.7 (Standard Deviation 12.5).
- Another mean score was 91.7 (Standard Deviation 20.5).
- An analysis showed a Mean Difference (Net) of -11.0 (95% Confidence Interval: -19.2 to -2.9) with a p-value of 0.01024, using a t-test, 2 sided method.
- Progression Free Survival:
- The 3-year survival probability was 83.2% (95% Confidence Interval: 75.8 to 91.3).
- Percentage of Participants Who Experienced an Acute Toxicity by Grade (counts of participants):
- 90 participants experienced an acute toxicity.
- 84 participants experienced an acute toxicity.
- 36 participants experienced an acute toxicity.
- 12 participants experienced an acute toxicity.
What this means
The results from this study provide important data on the long-term outcomes for patients with medulloblastoma and pineoblastoma treated with proton beam radiotherapy. The reported cumulative incidences of ototoxicity and endocrine dysfunction at both 3 and 5 years offer specific figures for clinicians and patients to consider regarding potential side effects. The 3-year progression-free survival probability of 83.2% indicates the treatment's efficacy in controlling disease progression. Furthermore, the statistically significant mean difference observed in neurocognitive effects suggests that proton beam therapy may have an impact on cognitive function, which warrants careful consideration in treatment planning and patient follow-up.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT01063114, titled "Proton Beam Radiotherapy for Medulloblastoma and Pineoblastoma", were posted on 2025-08-13 on clinicaltrials.gov.