SBRT for Prostate Cancer

Overseen By Debbie-Ann N Nathan, R.N.

Age: 18+

Sex: Male

Trial Phase: Phase 2

Sponsor: National Cancer Institute (NCI)

Must not be taking: Investigational agents, Chemotherapy

Disqualifiers: High-risk prostate cancer, Metastases, HIV, Hepatitis, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Approved in 4 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 4

Duration: 2 weeks

42 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to test a new type of radiation treatment called Stereotactic Body Radiation Therapy (SBRT) for men with early-stage prostate cancer that hasn't spread. Researchers hope that SBRT can target the cancer more precisely, potentially reducing side effects compared to traditional treatments like full prostate removal or radiation. The trial seeks men diagnosed with localized prostate cancer who haven't yet received any treatment. During the trial, participants will undergo targeted radiation sessions and regular follow-ups to assess the treatment's effectiveness over two years. As a Phase 2 trial, this research focuses on measuring the treatment's effectiveness in an initial, smaller group, offering participants a chance to contribute to important advancements in prostate cancer care.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications. However, if you are on systemic Androgen Deprivation Therapy (ADT) or chemotherapy, you cannot participate in the trial.

Is there any evidence suggesting that this treatment is likely to be safe for humans?

Research has shown that Stereotactic Body Radiation Therapy (SBRT) is a safe and well-tolerated treatment for prostate cancer. In one study, only 2.25% of patients experienced significant side effects, which were usually manageable. Another study found that SBRT offers similar survival rates to traditional radiation methods, with fewer side effects. These findings suggest that SBRT is a promising and safe option for treating prostate cancer. ^{1 2 3 4 5}

Why are researchers excited about this study treatment for prostate cancer?

Stereotactic Body Radiation Therapy (SBRT) is unique because it targets the tumor focus within the prostate with high precision, potentially sparing more of the surrounding healthy tissue compared to traditional radiation therapy. This precision is achieved using advanced imaging techniques like 18F-DCFPyL PET/CT, which allows for a more accurate assessment of the tumor's response. Researchers are excited about SBRT because it offers the potential for effective treatment with fewer side effects, possibly improving the quality of life for patients with prostate cancer.

What evidence suggests that SBRT might be an effective treatment for prostate cancer?

Research has shown that Stereotactic Body Radiation Therapy (SBRT), which participants in this trial will receive, can effectively treat prostate cancer. Long-term results from combined studies suggest that SBRT works well for low-risk prostate cancer and is generally safe. Studies indicate that prostate cancer responds well to the specific delivery method of SBRT, potentially making it more effective at targeting cancer cells with fewer side effects. Additionally, a similar method called adaptive radiation therapy has proven effective while also improving quality of life by reducing side effects. These findings support SBRT as a promising treatment for localized prostate cancer. ^{2 5 6 7 8}

Who Is on the Research Team?

Krishnan R Patel, M.D.

Principal Investigator

National Cancer Institute (NCI)

Are You a Good Fit for This Trial?

This trial is for men aged 18+ with untreated localized prostate cancer that hasn't spread outside the gland. They must be able to consent, have a performance status indicating they can carry out daily activities, and agree to use effective contraception during and up to 120 days post-treatment. Exclusions include those planning other treatments like ADT or chemotherapy, with high-risk prostate cancer features, prior curative treatment for prostate cancer, certain infections unless treated and cured, or conditions preventing MRI scans.

Inclusion Criteria

I can take care of myself but might not be able to do active work.

Ability of individual to understand and the willingness to sign a written informed consent document

My prostate cancer is located in one spot, confirmed by MRI and PET scans.

Exclusion Criteria

Participants with an AUA-SI/IPSS score > 18

Active urinary tract infection assessed by urinalysis

I have had treatment aimed at curing my prostate cancer before.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Treatment

Participants receive focal SBRT in two sessions, one week apart, targeting the prostate tumor

2 weeks

2 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment with repeat scans and blood tests

24 months

Regular visits at 1, 3, 6, 9, 12, 15, 18, 21, and 24 months

Biopsy Assessment

A biopsy is conducted to assess the impact of the treatment on prostate cancer

At 24 months

What Are the Treatments Tested in This Trial?

Interventions

• 18F-DCFPyL
• Stereotactic Body Radiation Therapy

Trial Overview The trial tests focal therapy using SBRT on patients with a single tumor in the prostate. It aims to see if this targeted radiation approach leads to fewer side effects than whole-gland surgery or radiation. Participants will undergo two sessions of SBRT about one week apart without sedation and follow-up for two years including scans (MRI & PSMA PET/CT) and blood tests.

How Is the Trial Designed?

Group I: 1/Focal SBRT Experimental Treatment 2 Interventions

Focal SBRT to the tumor focus within the prostate, with response assessed by biopsy and imaging, including 18F-DCFPyL PET/CT.

Stereotactic Body Radiation Therapy is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Stereotactic Body Radiation Therapy for:

• Non-small cell lung cancer (NSCLC)
• Melanoma
• Renal cell carcinoma (RCC)
• Prostate cancer
• Oligoprogressive cancers

Approved in European Union as Stereotactic Body Radiation Therapy for:

• Non-small cell lung cancer (NSCLC)
• Melanoma
• Renal cell carcinoma (RCC)
• Prostate cancer
• Oligoprogressive cancers

Approved in Canada as Stereotactic Body Radiation Therapy for:

• Non-small cell lung cancer (NSCLC)
• Melanoma
• Renal cell carcinoma (RCC)
• Prostate cancer
• Oligoprogressive cancers

Who Is Running the Clinical Trial?

National Cancer Institute (NCI)

Lead Sponsor

Trials

14,080

Recruited

41,180,000+

Published Research Related to This Trial

CyberKnife stereotactic ablative radiotherapy (SABR) for treating intermediate- to very-high-risk prostate cancer showed a high 3-year biochemical relapse-free survival rate of 90.2%, indicating its efficacy in managing this condition.

The treatment was well-tolerated, with no patients experiencing severe toxicity (≥ grade 3), and only mild genitourinary and gastrointestinal side effects were reported, suggesting a favorable safety profile.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stereotactic ablative radiotherapy with CyberKnife in the treatment of locally advanced prostate cancer: preliminary results. Fan, CY., Chao, HL., Huang, WY., et al.[2017]

In a study of 29 prostate cancer patients treated with stereotactic body radiotherapy (SBRT) using a Cyberknife, PSA levels showed a significant decrease over time, with a median nadir of 0.329 ng/mL achieved after 23 months.

The treatment demonstrated a favorable safety profile, with only 3% of patients experiencing Grade 2 urinary toxicities and no severe late rectal toxicities reported, indicating that SBRT is a feasible option for prostate cancer treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stereotactic body radiotherapy for prostate cancer: a preliminary report. Lee, YH., Son, SH., Yoon, SC., et al.[2022]

In a study of 33 patients with low- and intermediate-risk prostate cancer treated with CyberKnife SBRT, there was no biochemical failure, indicating high efficacy of the treatment over a median follow-up of 51 months.

The treatment resulted in manageable side effects, with no grade 3 acute or late toxicities reported, and most acute complications resolved within 2 months, suggesting a favorable safety profile.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Hypofractionated stereotactic body radiotherapy in low- and intermediate-risk prostate carcinoma. Kim, HJ., Phak, JH., Kim, WC.[2022]

Recent data indicate that CyberKnife SBRT (Stereotactic Body Radiation Therapy) for prostate cancer shows promising treatment outcomes with minimal toxicity, suggesting it could be a safe and effective option.

Despite ongoing controversy in the radiation oncology community, the radiobiologic characteristics of the prostate make it a strong candidate for SBRT, highlighting the need for further evaluation and acceptance of this treatment approach.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

CyberKnife radiosurgery for prostate cancer. Katz, AJ.[2022]

Stereotactic ablative radiotherapy (SABR) using Cyberknife demonstrated high effectiveness in treating stage I non-small-cell lung cancer, with 2-year local control, progression-free, and overall survival rates of 91.9%, 61.7%, and 84.8%, respectively, based on a study of 153 patients.

The treatment was generally safe, with only 8.1% of patients experiencing severe toxicities, including one case of grade 5 radiation pneumonitis, indicating that while SABR is effective, careful monitoring for side effects is necessary.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stereotactic Ablative Radiotherapy Using CyberKnife for Stage I Non-small-cell Lung Cancer: A Retrospective Analysis. Hayashi, K., Suzuki, O., Shiomi, H., et al.[2022]

Stereotactic body radiation therapy (SBRT) using CyberKnife for localized prostate cancer was found to be safe, with no severe treatment-related toxicities (grade 3 or higher) reported among 44 patients over a median follow-up of 40 months.

The treatment showed excellent efficacy, with a 100% cause-specific survival rate and progression-free survival rate, and a high biochemical failure-free rate of 90.8% for high-risk patients, particularly with the 34 Gy in 4 fractions regimen.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Image-guided stereotactic body radiation therapy for localized prostate cancer. Kang, JK., Cho, CK., Choi, CW., et al.[2022]

In a study of 84 low-risk prostate cancer patients treated with Stereotactic Ablative Body Radiotherapy (SABR), long-term quality of life (QOL) outcomes were generally positive, with a median follow-up of 50.8 months, although some patients reported declines in urinary (17.9%), bowel (26.2%), and sexual (37.5%) QOL domains.

Dosimetric factors such as rectal D1cc and penile bulb V35 were identified as significant predictors of worse QOL, highlighting the importance of adhering to strict dosimetric constraints to minimize side effects from treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dosimetric and patient correlates of quality of life after prostate stereotactic ablative radiotherapy. Elias, E., Helou, J., Zhang, L., et al.[2018]

The Cyberknife® system, used for stereotactic body radiation therapy (SBRT), shows promising efficacy in treating localized prostate cancer, with median PSA levels dropping significantly after treatment and biochemical progression-free survival rates ranging from 78.3% to 100% over a follow-up period of 4 to 60 months.

While the treatment is associated with mostly mild side effects (grade 1/2), there are reports of erectile dysfunction and some grade 3 toxicities, indicating a need for further long-term studies and randomized trials to establish its safety and effectiveness as a standard treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Current role of image-guided robotic radiosurgery (Cyberknife(®) ) for prostate cancer treatment. Seisen, T., Drouin, SJ., Phé, V., et al.[2018]

In a study of 230 men with early low-risk prostate cancer treated with stereotactic body radiotherapy (SBRT), the ten-year biochemical disease-free survival rate was an impressive 93%, indicating high efficacy of this treatment.

The treatment showed low toxicity, with only 10% of patients experiencing mild late urinary toxicity and 4% with late rectal toxicity, while quality of life scores for bowel and urinary function returned to baseline after initial declines.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stereotactic Body Radiotherapy for Low-Risk Prostate Cancer: A Ten-Year Analysis. Katz, A.[2020]

In a study comparing three radiotherapy techniques for prostate cancer treatment, RapidArc (RA) demonstrated superior target dose distribution and better sparing of critical structures compared to Cyberknife (CK) and Helical Tomotherapy (HT).

RA also had a better conformity index and gradient index, while CK required significantly more monitor units and beam-on time, indicating it may be less efficient than RA for delivering the same treatment margins.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cyberknife, Helical Tomotherapy and Rapid Arc SIB-SBRT Treatment Plan Comparison for Carcinoma Prostate. T K, B., K M, G., A, P., et al.[2021]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6043737/

Stereotactic ablative body radiotherapy in patients with ... There are moderately strong data supporting the use of radiotherapy (RT) for node positive prostate cancer (5) and the role of radiotherapy for metastatic ...

2. sciencedirect.com sciencedirect.com/science/article/pii/S2405632424000209

Stereotactic body radiation therapy (SBRT) for prostate ... Dose-fractionation sensitivity of prostate cancer deduced from radiotherapy outcomes of 5,969 patients in seven international institutional datasets: α/β = 1.4 ...

3. jamanetwork.com jamanetwork.com/journals/jamanetworkopen/fullarticle/2723641

Long-term Outcomes of Stereotactic Body Radiotherapy for ... This cohort study of pooled individual patient data assesses long-term outcomes after stereotactic body radiotherapy for low-risk and ...

4. thegreenjournal.com thegreenjournal.com/issue/S0167-8140(25)X0003-7?pageStart=26

May 2025 Prostate cancer focal boost versus no boost in 20 fraction external beam radiotherapy: a prospective cohort on dosimetry, toxicity and quality of life

5. clinicaltrials.gov clinicaltrials.gov/study/NCT06325046?term=John

Adaptive Radiation Therapy (ART) Stereotactic Ablative ... Shorter duration near margin-less ART may be just as effective at treating patients with localized prostate cancer but have less quality of life side effects ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5494208/

Cyberknife Radioablation of Prostate Cancer Stereotactic ablative radiotherapy of low and intermediate risk prostate cancer patients is a safe, well-tolerated and effective treatment modality (2.25% of ...

7. sciencedirect.com sciencedirect.com/science/article/pii/S2773160X25000078

The effectiveness and safety of stereotactic body ... The results show minor, non-significant differences in survival rates compared to conventional fractionation, a type of external radiation, after two and five ...

8. frontiersin.org frontiersin.org/journals/oncology/articles/10.3389/fonc.2023.1270498/full

and intermediate-risk prostate cancer: clinical outcomes ... Results: The 1-, 2-, and 5-year DFS rates were 92.9%, 92.9%, and 92.3%, respectively, while the 1-, 2-, and 5-year bDFS rates were 100%, 100%, and 95.7%, ...