Overview
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.
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.
Eligibility
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
