An interventional study of Pencil Beam Proton Therapy Treatment Machine in Prostate Cancer Patients Treated by Radiotherapy, sponsored by Hong Kong Sanatorium & Hospital. Recruiting at 1 site in Hong Kong. Open to male participants. Per ClinicalTrials.gov, last updated 2026-03-16.
Sponsored by Hong Kong Sanatorium & Hospital · Not applicable, Interventional, and Treatment
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.
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.
7,046 studies on the registry are indexed under Prostatic Neoplasms; 1,580 are open to participants now.
This study's planned enrollment of 35 is below the median of 60 across 5,348 interventional studies indexed under Prostatic Neoplasms.
Browse Prostatic Neoplasms studies →Hong Kong Sanatorium & Hospital is the lead sponsor of 9 studies on the registry; 1 is open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Radiation: Pencil Beam Proton Therapy Treatment Machine
2 fractions will be delivered to treat low- or intermediate- risk prostate cancer
Clinician-reported grade 2 or above genitourinary and gastrointestinal toxicity
Genitourinary and gastrointestinal toxicity were evaluated based on the Common Terminology Criteria for Adverse Events (CTCAE, version 5.0) developed by the National Cancer Institute (NCI). Adverse effects within 3 months post-treatment are classified as acute toxicities, while those occurring after 3 months are considered late toxicities.
Time frame: 3 months and 24 months after treatment completion with a minimum of 24 months of follow-up and an average of 5 years.
Change in patient reported gastrointestinal and genitourinary symptoms
Gastrointestinal and genitourinary health-related quality of life (HQOL) are measured using the Expanded Prostate Cancer Index Composite (EPIC) questionnaire, which is a validated comprehensive instrument to measure the health-related quality of life among men with prostate cancer. EPIC consists of 5 primary domains, including urinary function, bowel habits, sexual function, hormonal functions, and overall satisfaction. Responses to each question form a Likert scale and are transformed to a 0-100 scale for each domain and subdomain, higher scores representing better HQOL.
Time frame: before treatment to 3-months and 24-months after treatment completed
Biochemical Progression Free Survival (bPFS)
Biochemical progression-free survival (bPFS) among participants will be assessed during clinical follow-up. bPFS is defined as the duration of time a localized prostate cancer patient remains free from biochemical recurrence after treatment. Biochemical recurrence is defined as a prostate-specific antigen (PSA) increase of 2 ng/mL above the nadir based on the Phoenix criteria (nadir + 2 ng/mL), confirmed by a second PSA value obtained three or more weeks later.
Time frame: Treatment completion date to 5 years follow-up
Distant Metastasis Free Survival
Distant metastasis (DM) refers to the spread of cancer cells from the prostate to distant sites outside the pelvic region. DF will be assessed during clinical follow-up using prostate-specific membrane antigen positron emission tomography (PSMA-PET), MRI, and/or other clinical imaging in cases of persistent PSA progression or emergence of symptoms. Distant metastasis free survival is defined as the duration of time from treatment completion date to the date of distant metastasis diagnosis by clinical imaging or death.
Time frame: Treatment completion date to 5 years follow-up
Local Failure-Free Survival (LFFS)
Local Failure (LF) refers to recurrent prostatic mass diagnosed by digital rectal examination, clinical imaging techniques like PSMA-PET and/or MRI, or histopathological confirmation of recurrence by biopsy. Local failure-free survival is defined as the duration of time from treatment completion date to date of local failure diagnosis or death.
Time frame: Treatment completion date to 5 years follow-up
Regional Failure Free Survival (RFFS)
Regional Failure (RF) refers to recurrent in the regional lymph nodes diagnosed by clinical imaging techniques like PSMA-PET and/or MRI. Regional failure-free survival is defined as the duration of time from treatment completion date to date of regional failure diagnosis or death.
Time frame: Treatment completion date to 5 years follow-up
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No — The IPD cannot be shared due to hospital policy, which restricts the sharing of patient data-even in de-identified or masked form-to ensure compliance with privacy regulations and ethical safeguards.
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Hong Kong Sanatorium & Hospital