MR‑guided, PSMA/PET‑informed SBRT for prostate cancer that returned after prior radiation (TUMORNATOR II)

Trial Evaluating the Safety and Efficacy Of MR-Linac-Guided Radiotherapy as Salvage Treatment After External Beam Radiotherapy Recurrence (TUMORNATOR II)

This test tries MR‑Linac–guided stereotactic body radiotherapy, informed by PSMA/PET, (with possible short-term androgen deprivation) to see if it is safe and lowers serious urinary toxicity for men whose prostate cancer came back after external beam radiation.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 28 (estimated)
• Ages: 18 Years and up
• Sex: Male
• Sponsor: NYU Langone Health (Academic / other)
• Drugs / interventions: Radiation
• Locations: 1 site (New York, New York)
• Trial ID: NCT07142967 on ClinicalTrials.gov

What this trial studies

This single‑center interventional protocol uses MR‑Linac guidance and PSMA/PET imaging to precisely deliver stereotactic body radiotherapy (SBRT) as salvage treatment for biopsy‑proven intraprostatic recurrence after prior external beam radiotherapy. Patients may also receive androgen deprivation therapy according to protocol, and treatment planning uses MRI‑determined prostate size and toxicity risk measures. The primary focus is safety, with urinary toxicity outcomes measured at two years post‑treatment; other clinical and imaging outcomes will be monitored during follow‑up. Eligibility requires biopsy confirmation of local recurrence, adequate testosterone, acceptable performance status, and MRI prostate volume below 90 cc, and the trial is conducted at NYU Langone Health in New York.

Who should consider this trial

Good fit: Ideal candidates are men with biopsy‑proven intraprostatic recurrence after prior external beam radiotherapy, good performance status (KPS ≥80 or ECOG 0‑1), prostate MRI volume <90 cc, and testosterone ≥50 ng/dL.

Not a fit: Patients with extensive metastatic disease, prostate volumes ≥90 cc, very high baseline urinary symptoms (IPSS >20), or who cannot travel to the single New York study site are unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, this approach could offer a safer, more precise salvage radiation option that reduces serious urinary side effects for men with locally recurrent prostate cancer after prior radiation.

How similar studies have performed: MR‑guided adaptive radiotherapy and PSMA/PET‑directed treatments have shown promising safety and control in small single‑center series, but MR‑Linac–guided salvage SBRT after prior external beam radiotherapy remains relatively novel with limited multicenter data.

Eligibility criteria

Inclusion Criteria:

1. 18 years of age or older male participants
2. Biopsy proven intraprostatic prostate cancer after prior definitive external beam radiotherapy (moderate hypofractionation or Stereotactic Body Radiation Therapy (SBRT) acceptable).

   a. NOTE: Seminal vesicle involvement allowed
3. Pathology confirming recurrent disease must have evidence of viable cancer as indicated with pathology interpretation where a Gleason score can be assigned
4. Serum testosterone ≥ 50 ng/dL determined within 2 months prior to enrollment

   a. Prior Androgen Deprivation Therapy (ADT) use acceptable if testosterone level \>50ng/dL
5. At least 4 weeks must have elapsed from major surgery
6. Karnofsky Performance Scale (KPS) ≥ 80% or Eastern Cooperative Oncology Group (ECOG) 0-1
7. Prostate size as determined on MRI to be \< 90 cc.
8. International Prostatism Symptom Score (IPSS) ≤ 20
9. Patient must be available for follow-up. After 2 years of follow-up, upon completion of post-treatment biopsy, telephone, and chart review-based follow-up will be acceptable for up to 5 years
10. Presence of a T2 and/or DWI-visible prostatic lesion on mpMRI

    a. NOTE: Lesion visible on MRI required for enrollment but PSMA/PET avid lesion not required
11. Satisfy all MRI screening criteria and be willing to fill out the standard MRI screening form

Exclusion Criteria:

1. History of prostate brachytherapy (low dose rate or high dose rate)
2. Actively undergoing androgen deprivation therapy and/or anti-androgens at time of enrollment
3. CT or MRI or PET scan evidence of extraprostatic disease
4. Patients with one or more positive lymph nodes considered suspicious as determined by clinical assessment on MRI or CT or PET scan
5. History of another malignancy within the previous 2 years except for the following: adequately treated basal cell or squamous cell skin cancer, superficial bladder cancer, currently in complete remission, or any other cancer that has been in complete remission for at least 3 years
6. Patients with Crohn's disease or ulcerative colitis
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 MRCAT reconstruction
10. Contra-indications to receiving gadolinium contrast or PSMA radioligand
11. Karnofsky Performance Scale (KPS) \< 80 or ECOG 2+
12. Grade 3 or higher toxicity experienced after the initial course of External Beam Radiation Therapy (EBRT)
13. Disease free interval \< 2 years
14. Hx of Transurethral Resection Of Prostate (TURP) within the year
15. Prior high-intensity focused ultrasound (HIFU) or Cryotherapy
16. Prior history of urethral stricture
17. Unable to give informed consent
18. Unable to complete quality of life questionnaires

Where this trial is running

New York, New York

• NYU Langone Health — New York, New York, United States (Recruiting)

Study contacts

• Principal investigator: Michael Zelefsky, MD — NYU Langone Health
• Study coordinator: Michael Zelefsky, MD

Conditions Intraprostatic Prostate Cancer; prostate adenocarcinoma