Recruiting

MR-Guided Radiotherapy

Sponsor:

NYU Langone Health

Code:

NCT06542757

Conditions

Prostate Cancer

Eligibility Criteria

Sex: Male

Age: 18+

Healthy Volunteers: Not accepted

Interventions

1.5 T Elekta Unity MR-Linac system

Hydrogel rectal spacer (SpaceOAR)

Study Details

Brief summary:

The purpose of this study is to assess the impact of this MR-guided radiotherapy on tumor control of the dominant intraprostatic lesion among patients with intermediate risk prostate cancer. This study of Radiotherapy to the Prostate and Dominant Lesion Using Ultra-Hypofractionated, MR-adaptive Radiation Therapy aims to evaluate tumor control after definitive ultra-hypofractionated external beam radiation therapy (including a simultaneously delivered high-dose boost to a dominant lesion as detected on prostate magnetic resonance imaging (MRI)) in patients with intermediate-risk prostate cancer. This will incorporate the use of multiparametric MRI for target segmentation and the use of the MR-linac with adaptive radiation planning to treat the prostate gland, incorporating a dose boost to the dominant intraprostatic lesion (DIL) that is visible on T2-weighted and diffusion-weighted imaging and de-escalation of dose to the remainder of the prostate.

Conditions

Prostate Cancer

Study ID

NCT06542757

Start date

Dec 9, 2024

Status verified date

Mar, 2026

Completion date

Dec, 2029

Anticipated

Primary completion date

Dec, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Male

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. Intermediate-risk prostate cancer patients will be eligible for this study. Risk groups will be assigned as per National Comprehensive Cancer Network (NCCN) guidelines. Intermediate-risk patients will be defined as:

  • PSA 10-20 ng/ml or
  • Gleason score = 7 or
  • Clinical stage T2b/T2c (T2b: the tumor has spread to more than one-half of one side of the prostate, but not to both sides. T2c: the cancer has invaded both sides of the prostate)
2. Age > 18
3. Karnofsky Performance Status (KPS) > 80
4. Prostate size < 90 cc
5. Presence of a T2-visible prostatic lesion with maximum dimension of ≥ 0.5 cm and no more than two additional disease foci with a documented Prostate Imaging Reporting and Data System (PIRADS) 4-5 lesion
6. MRI findings: Lesion may contact the capsular edge, possible extracapsular extension (ECE) permitted
7. International Prostate Symptom Score < 18
8. Satisfy all MRI screening criteria and be willing to fill out the standard MRI screening form

Exclusion Criteria:

1. Gleason score >7
2. PSA >20 ng/mL
3. Prior or concurrent androgen deprivation therapy for prostate cancer
4. MRI findings: suspicious for/probable ECE
5. MRI findings: >2 disease foci identifiable
6. Evidence of metastatic disease on bone scan or MRI/CT
7. MRI ineligibility due to: the presence of a cardiac pacemaker, defibrillator, or other implanted metallic or electronic device which is considered MR unsafe; severe claustrophobia; inability to lie flat for the duration of the study; etc.
8. Metallic implant or device in the pelvis that might distort the local magnetic field and compromise quality of mp-MRI
9. Lateral pelvic separation greater than 50 cm and/or anterior-posterior separation greater than 35 cm which are incompatible with MR for Calculating ATtenuation (MRCAT) reconstruction
10. Contra-indications to receiving gadolinium contrast
11. KPS < 80
12. Pelvic or Prostate MRI or CT (MRI preferred) evidence of radiographic T3, T4, or N1 disease
13. Prior history of transurethral resection of the prostate
14. Prior history of urethral stricture
15. Prior history of pelvic irradiation
16. History of inflammatory bowel disease
17. Unable to give informed consent
18. Unable to complete quality of life questionnaires
19. Abnormal complete blood count, including any of the following:

  • Platelet count less than 75,000/ml
  • Hb level less than 10 gm/dl
  • White blood cell (WBC) less than 3.5/ml
  • Abnormal renal function tests (creatinine > 1.5)

Study Design

Enrollment

91 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: MRI-guided Intensity Modulated Radiotherapy

All patients will undergo the injection of a hydrogel rectal spacer (SpaceOAR) 1 week before simulation. Patients will undergo ultra-hypofractionated radiation utilizing MR-guided, daily online adaptive planning. Patients will receive 9 Gy/fraction for five fractions for a total dose of 45 Gy to the prostate DIL while the rest of the prostate will be treated to a minimum dose to the rest of the prostate of 30 Gy in five fractions. Radiation will be given every other day, Monday through Friday, until 5 treatments have been completed. Patients will be followed at three and six months after treatment, and every six months thereafter through month 24 (+/- 4 weeks).

Interventions

1.5 T Elekta Unity MR-Linac system

Patients will receive 9 Gy/fraction (45 Gy total) for five fractions to the DIL, while the remainder of the prostate will be treated to 30 Gy in 5 fractions.

Hydrogel rectal spacer (SpaceOAR)

A rectal spacer will be placed one week prior to simulation to achieve a separation of approximately 1 cm between the prostate and anterior rectal wall to further minimize rectal toxicity in these patients. The hydrogel will remain in the body for about 12 weeks.

Primary outcome measure

  • Negative biopsy rate 24 months post-treatment [ Time Frame: 24 months post-treatment ]
  • Serious toxicity rate 24 months post-treatment [ Time Frame: 24 months post-treatment ]

Central Contacts and Locations

Central contacts

Michael Zelefsky, M.D

212-263-4432CancerTrials@nyulangone.org

Locations

NYU Langone Health

Recruiting

New York, New York, United States, 10016

More Information

Sponsor

NYU Langone Health

Last update posted

Mar 11, 2026

Last verified

Mar, 2026

Keywords

  • intensity-modulated radiotherapy
  • MR-guided

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by NYU Langone Health on 2026-03-11.