Prostate MRI and Pylarify PSMA PET/CT

This is a voluntary research study to find out how using technology including advanced magnetic resonance imaging (MRI) and prostate-specific membrane antigen - positron emission tomography (PSMA-PET) scan imaging, in addition to combined prostate treatment using radiation therapy, brachytherapy (internal radiation treatment using small radioactive seeds placed inside the body) and androgen deprivation therapy (drug therapy to suppress hormones) can help doctors see, track and predict tumor response to treatment for prostate cancer patients. Participation in this study will consist of radiation planning and simulation, magnetic resonance imaging (MRI) and positron emission tomography and computed tomography scan (PET/CT). One MRI and PSMA PET/CT scan will be done prior to the start of first external beam radiation therapy (EBRT) fraction. At mid-treatment prior to the second brachytherapy fraction, an MRI and PSMA PET/CT will be done. A third scan will be performed after 75% testosterone recovery or 12 months post androgen deprivation therapy (ADT) \[whichever comes first\].

The goal of the study is to better understand how an individual tumor responds to radiation therapy and determine if advanced imaging can be used for prognostic purposes, especially to predict areas of local resistance and failure. The study population are patients with high risk prostate malignancy treated with a combination of external beam radiation therapy (EBRT)/brachytherapy (BT) and androgen deprivation therapy (ADT). Patients enrolled in this trial will undergo a pre-treatment MRI and PSMA PET/CT prior to the initiation of ADT and the first EBRT fraction, a mid-treatment MRI and PSMA PET/CT prior to second brachytherapy fraction, and a third MRI and PSMA PET/CT will be performed after 75% testosterone recovery or 12 months post-ADT (whichever comes first). The pre-treatment MRI and PSMA PET/CT is part of standard of care for prostate cancer workup, however all additional MRI and PSMA PET/CT mid-treatment or after treatment completion are additional research scans.

Eligibility Criteria:
Inclusion Criteria

* Planned definitive radiation for high-risk prostate cancer, radiotherapy plan to include high dose-rate (HDR) brachytherapy boost
* High-risk prostate cancer (tumor stage cT3a-cT4, OR Grade Group 4 or 5, OR prostate-specific antigen (PSA) \>20 ng/mL)
* Patients with clinically positive regional lymph nodes
* Patient planned to receive at least 12 months of androgen deprivation therapy
* Age ≥18 years
* No maximum age cutoff, however must have life expectancy \> 5 years based on patient's overall health
* Eastern Cooperative Oncology Group (ECOG) performance status 0-2
* Patient able to have 3-Tesla (3T) MRI per Beaumont Radiation Oncology MRI safety questionnaire

Exclusion Criteria:

* Eastern Cooperative Oncology Group (ECOG) performance status 3-5
* Metastatic disease
* Prior androgen deprivation therapy before study enrollment
* Prior radiation to pelvis
* Prior malignancy not achieving remission or with prognosis \< 5 years
* Synchronous malignancy confirmed or suspected
* Any patient not suitable for brachytherapy
* Severe claustrophobia precluding the acquisition of MRI
* Unable to safely have 3T MRI
* Cognitively impaired