Two-fraction Proton Therapy With MRI Guidance for Prostate Cancer: A Phase II Trial (PT2)

HKSH Medical Group

Status

Not yet enrolling

Conditions

Prostate Cancer Patients Treated by Radiotherapy

Treatments

Radiation: Pencil Beam Proton Therapy Treatment Machine

Study type

Interventional

Funder types

Industry

Identifiers

NCT07130682

REC-2025-08

Details and patient eligibility

About

This study is testing a shorter treatment method for prostate cancer using proton therapy (PT), which is very precise and may cause fewer side effects compared to traditional radiation. However, it is expensive and not easily accessible for many patients. To make it more affordable and accessible, this study is testing whether 2 fractions of stereotactic body proton therapy (SBPT) can be as safe and effective as the standard 5 sessions.

Full description

Proton therapy is an advanced form of radiation that precisely targets tumors while minimizing damage to healthy tissues. However, its high cost has limited patient access. For prostate cancer, studies have already shown that ultra-short radiation courses (as few as 2-5 sessions) using conventional X-ray-based stereotactic body radiation therapy (SBRT) provide excellent results with manageable side effects. This study aims to investigate whether 2-fraction stereotactic body proton therapy (SBPT) with magnetic resonance imaging (MRI) guidance and real-time on-board tumor tracking can achieve similar safety and efficiency as the standard 5-fraction SBPT, with the added benefit of lower costs and greater convenience for patients.

Enrollment

35 estimated patients

Sex

Male

Volunteers

No Healthy Volunteers

Inclusion criteria

Men aged < 18 years with histologically confirmed low- or intermediate-risk prostate cancer per NCCN guidelines
Eastern Cooperative Oncology Group (ECOG) performance status <2
Ability to undergo magnetic resonance imaging (MRI) simulation scans without absolute contraindications, such as cardiac implantable electronic devices
Ability to complete the Expanded Prostate Cancer Index Composite (EPIC) questionnaire

Exclusion criteria

History of inflammatory bowel disease or other cancers (except prostate cancer)
Prior pelvic radiotherapy, chemotherapy, radical prostatectomy, cryosurgery, or focal therapy (e.g. high-intensity focused ultrasound [HIFU]) for prostate cancer
History of bladder neck or urethral stricture
Transurethral resection of the prostate (TURP) < 8 weeks prior to SBPT
Prostate volume > 100cc on MRI
Unilateral or bilateral hip replacements
Nodal or distant metastases, as indicated by computed tomography (CT), MRI, or prostate-specific membrane antigen (PSMA) positron emission tomography (PET) scans
Previous androgen deprivation therapy (ADT) lasting more than 6 months