SBRT vs Hypofractionated Radiotherapy for Recurrent Prostate Cancer

Overseen By Clinical Trials Referral Office

Age: 18+

Sex: Male

Trial Phase: Phase 3

Sponsor: Mayo Clinic

Disqualifiers: Previous pelvic radiation, Prior chemotherapy, Active rectal diverticulitis, others

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

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

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

Compensation: Varies

Number of Visits: 9

Duration: 1-6 weeks

118 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment SBRT vs Hypofractionated Radiotherapy for Recurrent Prostate Cancer?

Research shows that stereotactic body radiotherapy (SBRT), a form of hypofractionated treatment, has been effective in controlling prostate cancer with good outcomes over several years. Studies indicate that SBRT can manage the disease without increasing side effects, making it a promising option for prostate cancer treatment. ^{1 2 3 4 5}

Is SBRT or Hypofractionated Radiotherapy safe for treating prostate cancer?

Research shows that SBRT and Hypofractionated Radiotherapy are generally safe for treating prostate cancer, with most patients experiencing mild to moderate side effects like urinary and gastrointestinal issues, which typically return to normal within six months. ^{2 4 6 7 8}

How is the treatment SBRT different from other treatments for recurrent prostate cancer?

SBRT (Stereotactic Body Radiation Therapy) is unique because it delivers high doses of radiation in fewer sessions compared to traditional radiation therapy, which can lead to improved patient outcomes and convenience. It uses advanced imaging to precisely target the cancer, potentially reducing damage to surrounding healthy tissue. ^{1 2 5 6 9}

What is the purpose of this trial?

This phase III trial tests the side effects of stereotactic body radiation therapy (SBRT) compared to hypofractionated radiotherapy for treating patients with prostate adenocarcinoma that has come back after a period of improvement (recurrent) or that has spread from where it first started (primary site) to a limited number of sites (oligometastatic). SBRT is a type of external radiation therapy that uses special equipment to position a patient and precisely deliver radiation to tumors in the body (except the brain). The total dose of radiation is divided into smaller doses given over several days. This type of radiation therapy helps spare normal tissue. Hypofractionated radiation therapy delivers higher doses of radiation therapy over a shorter period of time and may kill more tumors cells and have fewer side effects. SBRT may work just as well as hypofractionated radiation therapy at treating patients with biochemically recurrent or oligometastatic prostate cancer, but with a shorter treatment time and possibly fewer side effects.

Research Team

Carlos E. Vargas, MD

Principal Investigator

Mayo Clinic

Eligibility Criteria

This trial is for men with prostate adenocarcinoma that has either returned after initial treatment or spread to a few other places. Participants should have undergone some prior therapy and be able to undergo imaging tests like PET scans, bone scans, and MRIs.

Inclusion Criteria

My prostate cancer has spread to no more than 5 places.

My prostate cancer was confirmed through a tissue examination.

I can care for myself and am up and about more than 50% of my waking hours.

Exclusion Criteria

Major medical, addictive, or psychiatric illness which in the investigator's opinion, will prevent the consent process, completion of the treatment and/or interfere with follow-up. (Consent by legal authorized representative is not permitted for this study)

I have had radiation therapy to my pelvic area before.

I have had chemotherapy for prostate cancer before.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Treatment

Participants undergo either SBRT over 1-2 weeks or hypofractionated radiation therapy over 4-6 weeks

1-6 weeks

5 visits (SBRT) or 20 visits (hypofractionated)

Follow-up

Participants are monitored for safety and effectiveness after treatment

5 years

Follow-up at 3 months, 12 months, annually until year 5, then every other year

Treatment Details

Interventions

• Hypofractionated Radiation Therapy
• Stereotactic Body Radiation Therapy

Trial Overview The study compares two radiation therapies: SBRT, which delivers precise doses over several days aiming to minimize damage to healthy tissue; versus hypofractionated radiotherapy, which gives higher doses in a shorter time frame potentially killing more tumor cells.

Participant Groups

Group I: Group II (Hypofractionated radiation therapy) Experimental Treatment 7 Interventions

Patients undergo hypofractionated radiation therapy over 15-20 minutes once per day for a total of 20 treatments over 4-6 weeks in the absence of disease progression or unacceptable toxicity. Patients may receive androgen deprivation therapy for up to 18 months, as clinically indicated. Patients undergo bone scan and PET at screening and treatment failure, and undergo MRI and blood sample collection throughout the study.

Group II: Group I (SBRT) Experimental Treatment 7 Interventions

Patients undergo SBRT over 15-20 minutes every other day for a total of 5 treatments over 1-2 weeks in the absence of disease progression or unacceptable toxicity. Patients may receive androgen deprivation therapy for up to 18 months, as clinically indicated. Patients undergo bone scan and PET at screening and treatment failure, and undergo MRI and blood sample collection throughout the study.

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

Approved in United States as Hypofractionated Radiotherapy for:

• Soft tissue sarcoma
• Extremity soft tissue sarcoma

Approved in European Union as Hypofractionated Radiotherapy for:

• Soft tissue sarcoma
• Extremity soft tissue sarcoma

Approved in Canada as Hypofractionated Radiotherapy for:

• Soft tissue sarcoma
• Extremity soft tissue sarcoma

Who Is Running the Clinical Trial?

Mayo Clinic

Lead Sponsor

Trials

3,427

Recruited

3,221,000+

Findings from Research

In a study of 41 low-risk prostate cancer patients treated with hypofractionated stereotactic body radiotherapy (SBRT), the 5-year biochemical progression-free survival rate was an impressive 93%, indicating strong efficacy of this treatment.

The treatment was well-tolerated, with acute side effects resolving within 1-3 months and no severe (grade 4) toxicities reported, highlighting the safety of SBRT for localized prostate cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stereotactic body radiotherapy for low-risk prostate cancer: five-year outcomes. Freeman, DE., King, CR.[2022]

In a study of 304 prostate cancer patients treated with CyberKnife stereotactic body radiotherapy (SBRT), the treatment demonstrated excellent biochemical control rates, with 97% of low-risk, 90.7% of intermediate-risk, and 74.1% of high-risk patients remaining free from biochemical recurrence at 5 years.

The treatment was associated with low toxicity, as no patients experienced severe acute complications, and only a small percentage had Grade II urinary or rectal toxicities, indicating that SBRT is a safe and effective option for prostate cancer management.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Stereotactic body radiotherapy for localized prostate cancer: disease control and quality of life at 6 years. Katz, AJ., Santoro, M., Diblasio, F., et al.[2021]

In a study of 41 patients with high-risk localized prostate cancer, combining whole-pelvis irradiation with a stereotactic body radiotherapy (SBRT) boost resulted in a high 4-year biochemical failure-free survival rate of 91.9%, indicating effective cancer control.

The treatment was associated with minimal toxicity, with no severe (grade 3) gastrointestinal or genitourinary side effects reported, suggesting that this approach is safe for patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The early result of whole pelvic radiotherapy and stereotactic body radiotherapy boost for high-risk localized prostate cancer. Lin, YW., Lin, LC., Lin, KL.[2020]

In a study of 12 localized prostate cancer cases, Tomotherapy (HT) demonstrated superior dosimetric results compared to Cyberknife (CK), achieving better dose homogeneity, target coverage, and conformity, which are crucial for effective treatment.

HT also predicted lower late rectal toxicity and resulted in a significantly lower integral dose to the body, suggesting that it may offer clinical benefits by reducing the risk of side effects associated with radiation therapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dosimetric and radiobiological comparison of Cyberknife and Tomotherapy in stereotactic body radiotherapy for localized prostate cancer. Chen, CY., Lee, LM., Yu, HW., et al.[2018]

In a study involving 51 prostate cancer patients treated with stereotactic body radiotherapy (SBRT), the treatment showed promising outcomes with manageable toxicity levels, as no patients experienced severe (grade 3+) side effects during the initial follow-up period.

The median follow-up of 14.5 months revealed a low prostate-specific antigen level of 1.3 ng/ml at 13-18 months post-treatment, indicating effective disease control in this cohort.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prostate stereotactic body radiotherapy—first UK experience. Tree, AC., Ostler, P., Hoskin, P., et al.[2022]

In a study of 67 patients with low-risk prostate cancer treated with stereotactic body radiotherapy (SBRT), significant late bladder and rectal toxicities were infrequent, with no grade 4 toxicities reported and only 3% experiencing grade 3 bladder toxicity.

The 4-year PSA relapse-free survival rate was 94%, indicating that SBRT is effective in controlling prostate cancer and should be considered as a treatment option alongside other therapies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Long-term outcomes from a prospective trial of stereotactic body radiotherapy for low-risk prostate cancer. King, CR., Brooks, JD., Gill, H., et al.[2022]

A systematic review of studies on stereotactic body radiation therapy (SBRT) for prostate cancer found that most patients experienced mild to moderate side effects, with severe toxicity occurring in less than 3% of cases, indicating that SBRT is generally well tolerated.

The review identified important dosimetric factors that influence toxicity, such as recommended dose constraints for the bladder, urethra, and rectum, which can help optimize treatment safety and effectiveness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Prostate Stereotactic Body Radiation Therapy: An Overview of Toxicity and Dose Response. Wang, K., Mavroidis, P., Royce, TJ., et al.[2022]

In a study involving 24 patients with intermediate- to high-risk prostate cancer, hypofractionated stereotactic body radiation therapy (SBRT) using the CyberKnife system showed promising results, with a significant decrease in median PSA levels from 10.6 ng/ml to 1.5 ng/ml within 6 months post-treatment.

The treatment was well tolerated, with only mild acute urinary and gastrointestinal toxicities reported, and no severe Grade 3 or greater toxicities, indicating a favorable safety profile for this approach.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A pilot study of intensity modulated radiation therapy with hypofractionated stereotactic body radiation therapy (SBRT) boost in the treatment of intermediate- to high-risk prostate cancer. Oermann, EK., Slack, RS., Hanscom, HN., et al.[2022]

The CyberKnife (CK) system provided significantly better dose distribution for prostate cancer treatment compared to both volumetric arc radiotherapy (VMAT) and intensity-modulated radiotherapy (IMRT), with a higher mean planning target volume dose (39.58 Gy vs. 36.25 Gy).

CK resulted in a lower mean dose to the rectum, indicating improved safety for this organ, while also achieving better conformity and homogeneity indices, although VMAT and IMRT are still considered acceptable alternatives due to their comparable performance.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Does CyberKnife improve dose distribution versus IMRT and VMAT on a linear accelerator in low-risk prostate cancer? Borowicz, DM., Skrobała, A., Kruszyna-Mochalska, M., et al.[2023]

References

1. England pubmed.ncbi.nlm.nih.gov

Stereotactic body radiotherapy for low-risk prostate cancer: five-year outcomes. [2022]

2. England pubmed.ncbi.nlm.nih.gov

Stereotactic body radiotherapy for localized prostate cancer: disease control and quality of life at 6 years. [2021]

3. Switzerland pubmed.ncbi.nlm.nih.gov

The early result of whole pelvic radiotherapy and stereotactic body radiotherapy boost for high-risk localized prostate cancer. [2020]

4. Netherlands pubmed.ncbi.nlm.nih.gov

Dosimetric and radiobiological comparison of Cyberknife and Tomotherapy in stereotactic body radiotherapy for localized prostate cancer. [2018]

5. England pubmed.ncbi.nlm.nih.gov

Prostate stereotactic body radiotherapy—first UK experience. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

Long-term outcomes from a prospective trial of stereotactic body radiotherapy for low-risk prostate cancer. [2022]

7. United States pubmed.ncbi.nlm.nih.gov

Prostate Stereotactic Body Radiation Therapy: An Overview of Toxicity and Dose Response. [2022]

8. United States pubmed.ncbi.nlm.nih.gov

A pilot study of intensity modulated radiation therapy with hypofractionated stereotactic body radiation therapy (SBRT) boost in the treatment of intermediate- to high-risk prostate cancer. [2022]

9. Poland pubmed.ncbi.nlm.nih.gov

Does CyberKnife improve dose distribution versus IMRT and VMAT on a linear accelerator in low-risk prostate cancer? [2023]