PSMA-PET Guided Radiotherapy

Study Overview
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Brief Summary
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PSMA PET/CT has demonstrated higher sensitivity in detecting metastases than current imaging standard of care (CT and bone scan). [18F]DCFPyL is a promising high-sensitivity second generation PSMA-targeted urea-based PET probe. The hypothesis is that definitive radiotherapy (RT) informed by PSMA-PET findings will lead to improved cancer control outcomes compared to RT guided by conventional staging only. This study utilizes cmRCT design in companion to PERA (Partnership initiative for the Evaluation of technological innovation in Radiotherapy).

Official Title
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PSMA-PET Guided Radiotherapy in Patients With High-Risk, Recurrent, or Oligometastatic Prostate Cancer

Conditions
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Prostate Cancer

Intervention / Treatment
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* Radiation: PSMA -PET/CT simulation
* Radiation: Standard-care simulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Enrolled in PERA (CHUM CER 17.0.32) and consented to contact for investigational trials. Histological diagnosis of prostate cancer planned for curative-intent radiotherapy. ECOG 0-1 Charlson Cormobidity Index ≤ 4 High-risk of distant metastases as defined by any of: Oligometastases (≤5) (regional or distant) identified on conventional staging, with ≤ 3 metastasis in any non-bone organ. For a spine metastasis, direct involvement of adjacent spinal segments would still be considered as one tumour. For nodal metastases, more than one involved lymph node in the same ipsilateral nodal region/chain would still count as one tumour. Defined nodal regions for this protocol include inguinal, external iliac, internal iliac, common iliac, retroperitoneal, hilar/mediastinal, anterior cervical, posterior cervical, and axillary. Metastases in all other organs that are within 1cm of each other will be considered as one tumour. Subjects with newly diagnosed high-risk (NCCN) localized prostate cancer and CAPRA score 6-10. Subjects with a prior history of treated prostate cancer (RP or RT), and biochemical failure (Phoenix-RT or>0.2ng/ml-RP) Standard staging (bone scan, CT pelvis) within 12 weeks of consent. Exclusion Criteria: Prior androgen deprivation therapy terminated < 12 months prior to enrollment. Prior or planned PET scan.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Patients are randomly selected from a standard-care cohort.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PSMA-PETgRT<br>PSMA-PET/CT imaging is performed during treatment planning. Treating physicians are informed of test results and advised to include up to 5 PSMA-PET avid sites distant to the prostate gland, if present, in the radiotherapy treatment plan. | Radiation: PSMA -PET/CT simulation<br>* PET/CT simulation. If no additional lesions detected: RT as planned per standard care. If PSMA-PET/CT imaging consistent with oligometastases (1-5 lesions): all lesions must be treated with definitive RT. If PSMA-PET/CT imaging consistent with widely metastatic disease (>5 lesions): treatment of all detected disease with RT is not recommended, but treatment of the primary site as initially planned is encouraged.<br>|
| Active Comparator: Standard<br>Patient's receive standard care radiotherapy and do not undergo PSMA-PET/CT imaging. | Radiation: Standard-care simulation<br>* No PSMA-PET/CT as part of RT treatment planning.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Failure-free survival | Time to failure event | 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute and delayed toxicities | Rate of Attributable Gr2+ toxicities (CTCAE v4.0) | 5 years | 
| Rate of failure | Event rates | 5 years | 
| Survival | Event rates | 5 years | 
| Health-related quality of life | Qol measures | 5 years | 
| Detection yield of PSMA PET imaging | Rate of new lesions identified on imaging | 2 years |