Carbon Ion Radiotherapy in Frail Patients With Pancreatic Cancer

Official title

Carbon Ion Radiotherapy in Frail Patients With Pancreatic Cancer: A Prospective Phase II Study

Overview

"This prospective, single-arm phase II study aims to evaluate the efficacy and safety of carbon ion radiotherapy in frail patients with histologically confirmed, non-metastatic pancreatic cancer who are not eligible for surgery or systemic chemotherapy. Frail status is defined as a Clinical Frailty Scale (CFS) score ≥4 or the presence of significant medical comorbidities limiting aggressive treatment. Carbon ion radiotherapy, known for its superior dose distribution and high linear energy transfer, may offer improved tumor control with acceptable toxicity in this vulnerable population. This study will assess overall survival, progression-free survival, local control, toxicity, and quality of life.

Detailed description

"This prospective, single-arm phase II study evaluates the efficacy and safety of carbon ion radiotherapy in frail patients with non-metastatic pancreatic cancer who are not eligible for surgery or systemic chemotherapy due to a Clinical Frailty Scale (CFS) score ≥4 or significant medical comorbidities. carbon ion radiotherapy provides superior dose distribution and higher biological effectiveness compared with conventional X-ray radiotherapy, offering a potentially effective treatment option for this clinically vulnerable population.

Participants will undergo baseline evaluations including imaging (CT/MRI/PET-CT), laboratory tests, tumor markers, frailty assessment, and quality-of-life questionnaires (EORTC QLQ-C30 and FACT-Hep). Carbon ion radiotherapy will be delivered using 4D-CT-based planning, with either 55.2 Gy (RBE) in 12 fractions or 40-48 Gy (RBE) in 4 fractions. Target volumes include the primary tumor and high-risk peripancreatic regions, while organs-at-risk such as the stomach, duodenum, bowel, liver, kidneys, and spinal cord follow strict dose constraints. Weekly on-treatment assessments will monitor acute toxicity using CTCAE v5.0, and adaptive planning will be performed if needed.

Post-treatment follow-up will occur at 1-3 months and every 3-6 months thereafter for up to 2 years, including imaging, toxicity evaluation, tumor marker assessment, and repeated QOL surveys.

The primary endpoint is overall survival. Secondary endpoints include progression-free survival, local control, treatment-related toxicity, quality of life, and tumor marker changes. Survival analyses will use Kaplan-Meier and Cox regression methods, and quality-of-life and toxicity outcomes will be summarized descriptively.

Interventions

• Other Carbon Ion Radiotherapy
  Carbon ion radiotherapy is delivered with two possible regimens: 55.2 Gy in 12 fractions over 3 weeks or 40-48 Gy in 4 fractions over 1 week. Treatment planning is performed using contrast-enhanced CT and 4D-CT to assess respiratory motion. Target volumes include the gross tumor volume and high-risk peripancreatic regions, while organs at risk (stomach, duodenum, bowel, liver, kidneys, spinal cord) follow strict dose constraints. Treatments are delivered once daily for the 12-fraction regimen or

Primary outcome measures

• Overall survival in frail patients with pancreatic cancer receiving carbon ion radiotherapy [Time frame: Up to 2 years from the start of treatment]

Secondary outcome measures (6)

• Progression-free survival [Time frame: Up to 2 years from the start of treatment]
• Local control rate [Time frame: Up to 2 years from the start of treatment]
• Quality of Life: EORTC QLQ-C30 Score [Time frame: Baseline, end of radiotherapy, and every 3-6 months up to 2 years]
• Treatment-related toxicity [Time frame: During radiotherapy and every 3-6 months up to 2 years]
• Tumor marker changes (CA 19-9, CEA) [Time frame: Baseline and every follow-up visit up to 2 years]
• Quality of Life: FACT-Hep Score [Time frame: Baseline, end of radiotherapy, and every 3-6 months up to 2 years]

Eligibility criteria

Inclusion criteria

\- Histologically confirmed pancreatic cancer without distant metastasis.

Not eligible for surgery or systemic chemotherapy, defined as:

Clinical Frailty Scale (CFS) score ≥ 4, or Significant medical comorbidities precluding standard treatment. Patients who decline surgery and chemotherapy after adequate counseling. Age ≥ 19 years. Able to provide written informed consent. Eligible and willing to receive carbon ion radiotherapy.

Exclusion criteria

• Age < 19 years. Presence of distant metastasis at baseline imaging (CT/MRI/PET-CT). Active or uncontrolled infection that may interfere with treatment. Active bleeding or bleeding tendency requiring immediate medical intervention. Pregnant or breastfeeding women. Any condition that, in the investigator's judgment, makes participation unsafe or inappropriate (e.g., severe organ dysfunction preventing radiotherapy).

Inability to comply with study procedures or follow-up schedule.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Non-randomized

Model

Single group

Masking

Open label

Primary purpose

Treatment

Study locations

South Korea · 1 center

• Yonsei University Health System, Severance Hospital — Seoul

Identifiers

NCT: NCT07257523 · 4-2025-0681

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗