Limited Target Volume Radiotherapy After Glioblastoma Surgery

A Single-arm Phase II Non-inferiority Clinical Study of Limited Target Volume Radiotherapy After Glioblastoma Surgery

Research on radiotherapy target volumes for glioblastoma is increasingly focused on exploring more limited yet effective irradiation fields, aiming to achieve local control while minimizing acute and long-term neurotoxicity. Previous retrospective analysis by investigators revealed that local recurrences of glioblastoma are predominantly confined to a narrow margin around the original lesion: 98.3% of recurrences occurred within 0.5 cm of the original T2-FLAIR abnormality, 94.8% within 1 cm of the original T1-enhanced region. These findings have been cited in the ESTRO-EANO treatment guidelines. Building on this evidence, investigators plan to conduct a single-arm, phase II clinical trial to systematically evaluate the efficacy and safety of a 1 cm radiotherapy target volume in post-operative glioblastoma patients.Eligible patients with glioblastoma who have undergone surgical resection will be selected to receive limited-field radiotherapy. The target volume will be defined based on the postoperative MRI enhancing lesion: a 1 cm margin will be added to form the clinical target volume (CTV), followed by a further 0.3 cm margin to create the planning target volume (PTV). A total dose of 60 Gy will be delivered in 30 fractions (2 Gy per fraction, 5 fractions per week). Concurrent and adjuvant chemotherapy will be administered per standard guidelines. The primary efficacy endpoints are the 6-month progression-free survival rate and the incidence of symptomatic radiation-induced brain necrosis of grade 3 or higher. Secondary endpoints include overall survival, patterns of recurrence, neurocognitive function, and quality of life.

Study Overview

• Status: Not yet recruiting
• Conditions: Glioblastoma (GBM)
• Intervention / Treatment: Radiation: limited-field radiotherapy

• Study Type: Interventional
• Enrollment (Estimated): 79
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ziwei Tu; Phone Number: 13755793552; Email: tuziwei198803@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Aged between 18 and 70 years.
• Diagnosed with glioblastoma by surgical pathology, with the extent of resection achieving maximal safe resection.
• Within 2 to 6 weeks after surgery
• In good physical condition with a Karnofsky Performance Status (KPS) score ≥ 60.
• Hematological, hepatic, and renal functions are essentially normal.
• Signed informed consent, willing to undergo treatment and follow-up as stipulated in the study protocol.

Exclusion Criteria:

• Prior history of cranial radiotherapy or other malignant tumors.
• Severe dysfunction of vital organs (e.g., heart, liver, kidneys) that precludes tolerance to radiotherapy.
• Active infection, immune system disorders, or other serious chronic diseases.
• Pregnancy or lactation.
• Psychiatric disorders or severe cognitive impairment that compromises the ability to cooperate with treatment and follow-up.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: limited-field radiotherapy Group	Radiation: limited-field radiotherapy; limited-field radiotherapy + Concurrent and adjuvant TMZ chemotherapy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
6m PFS	6-month progression-free survival rate	up to 6 month
incidence of symptomatic radiation-induced brain necrosis of grade 3 or higher		Up to 24 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
OS	overall survival	Up to 24 months
Location of first recurrence relative to radiation field (in-field, marginal, or distant)	The spatial relationship between the first documented site of disease recurrence/progression and the original radiation treatment plan will be determined by a core imaging laboratory. Recurrent lesions will be co-registered with the original planning CT/MRI and radiation dose distribution. Classification is based on the volume of the recurrent lesion covered by the 95% isodose line of the original prescription dose: In-field recurrence: >80% of the recurrent lesion's volume is within the 95% isodose line. Marginal recurrence: 20% to 80% of the recurrent lesion's volume is within the 95% isodose line. Distant recurrence: <20% of the recurrent lesion's volume is within the 95% isodose line. This classification criteria is adapted from the dosimetric analysis methods commonly used in radiotherapy studies (e.g., Patterns offailure for glioblastoma multiforme following limited-margin radiation and concurrent temozolomide. Radiation oncology 2014, 9:130.)	Up to 24 months
Health-Related Quality of Life as assessed by the EORTC QLQ-C30 Global Health Status / QoL scale	Score on the Global Health Status / Quality of Life scale (Items 29 & 30) of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30). Scale range: 0-100. A higher score indicates a better overall quality of life.	Up to 24 months
Disease-Specific Quality of Life as assessed by the EORTC QLQ-BN20 summary score	Summary score of the European Organization for Research and Treatment of Cancer Brain Cancer Module (EORTC QLQ-BN20). This scale assesses symptoms and issues specific to brain tumor patients (e.g., future uncertainty, visual disorder, motor dysfunction). Scale range and interpretation should be specified	Up to 24 months
Quality of Life as assessed by the FACT-Br Total Score	Total score of the Functional Assessment of Cancer Therapy - Brain (FACT-Br). This questionnaire assesses physical, social, emotional, functional well-being, and additional concerns specific to brain tumor patients. Scale range: 0-200. A higher score indicates better quality of life.	Up to 24 months
Cognitive function assessed by Mini-Mental State Examination (MMSE) score	Cognitive function assessed by the Mini-Mental State Examination (MMSE). Scores range from 0 to 30, with higher scores indicating better cognitive function.	Up to 24 months
Cognitive function assessed by Montreal Cognitive Assessment (MoCA) score	Cognitive function assessed by the Montreal Cognitive Assessment (MoCA). Scores range from 0 to 30, with higher scores indicating better cognitive function.	Up to 24 months.

Collaborators and Investigators

• Sponsor: Jiangxi Provincial Cancer Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2030

Study Registration Dates

• First Submitted: January 6, 2026
• First Submitted That Met QC Criteria: January 18, 2026
• First Posted (Actual): January 26, 2026

Study Record Updates

• Last Update Posted (Actual): January 30, 2026
• Last Update Submitted That Met QC Criteria: January 28, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms; Neoplasms by Histologic Type; Neoplasms, Glandular and Epithelial; Astrocytoma; Glioma; Neoplasms, Neuroepithelial; Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms, Nerve Tissue; Glioblastoma
• Other Study ID Numbers: 2025ky249

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No