Treating Prostate Cancer That Has Come Back After Surgery With Apalutamide and Targeted Radiation Using PET/CT Imaging

Inclusion Criteria:

STEP 0: REGISTRATION ELIGIBILITY CRITERIA
Patient must have had a radical prostatectomy (RP) as definitive therapy for histopathologically-proven prostatic adenocarcinoma

Patient must have biochemical recurrence (BCR) after RP, with rising PSA defined as follows:

If time to biochemical recurrence, (defined as time to first detectable PSA after RP) is < 12 months, a minimum PSA level of >= 0.2 ng/mL and a confirmatory reading of >= 0.2 ng/mL is required, per the American Urological Association (AUA) definition (this includes patients with a persistent PSA reading of at least 0.2 ng/mL)

If time to biochemical recurrence, (defined as time to first detectable PSA after RP) is >= 12 months, a minimum absolute PSA of 0.5 ng/mL is required

NOTE: Qualifying PSA values per above must be collected at least 4 weeks after RP, with confirmatory persistent or elevated PSA collected at any subsequent time point
Patient must be negative or equivocal for extrapelvic metastatic disease by conventional imaging modalities (CIM) (i.e., bone scans, pelvic CT, or pelvic MRI), which must be done within 10-12 weeks prior to registration. Extra-pelvic metastases is defined as any osseous metastases and/or any extrapelvic soft tissue, lymph nodes and organ metastases; extra-pelvic is defined as superior to common iliac bifurcation, outside of standard prostate bed + whole pelvis nodal RT fields
Baseline PET/CT scan (PET1) are eligible for this study if the SOC PET scan using 18F-fluciclovine (Axumin) is completed during step 0 registration or up to 12 weeks prior to step 0 registration. The PET/CT scanners must meet scanner qualifications and scans must have an interpretation (or confirmation of an institutional clinical read) by a nuclear medicine physician or radiologist who has undergone 18F-fluciclovine (Axumin) reader training
Patient must be a candidate for standard-of-care (SOC) post-prostatectomy radiation therapy (RT) to the prostate bed and pelvic nodes with androgen deprivation therapy (adjuvant)
Patient must have the ability to provide written informed consent
Patient must have an Eastern Cooperative Oncology Group (ECOG) performance status 0-2
Patient must be able to lie flat and still for approximately 20-30 minutes or otherwise tolerate a PET/CT scan and radiation treatment planning and delivery
Patient must be at a participating institution, which has agreed to perform the imaging research studies, completed the ECOG-American College of Radiology Imaging Network (ACRIN) defined PET/CT scanner qualification procedures and received ECOG-ACRIN PET/CT scanner approval
Leukocytes >= 3,000/mcL (obtained within 4 weeks prior to registration)
Absolute neutrophil count >= 1,500/mcL (obtained within 4 weeks prior to registration)
Platelets >= 100,000/mcL (obtained within 4 weeks prior to registration)
Total bilirubin =< institutional upper limit of normal (ULN) (obtained within 4 weeks prior to registration)
Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase [SGOT])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT]) =< 2.5 x institutional ULN (obtained within 4 weeks prior to registration)
Glomerular filtration rate (GFR) > 35 mL/min estimated by Cockcroft-Gault or measured directly by 24 hour urine creatinine (obtained within 4 weeks prior to registration)
Human immunodeficiency virus (HIV)-infected patients on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial
For patients with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated
Patients with a history of hepatitis C virus (HCV) infection must have been treated and cured. For patients with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load
Patients with known history or current symptoms of cardiac disease, or history of treatment with cardiotoxic agents, should have a clinical risk assessment of cardiac function using the New York Heart Association Functional Classification. To be eligible for this trial, patients should be class I or II (by patient symptoms) or A or B (by objective assessment)
STEP 1: RANDOMIZATION ELIGIBILITY CRITERIA
Patient must have completed a baseline SOC PET scan (PET1) with results of extra-pelvic metastases involvement known (positive or negative)
For patients with negative extra-pelvic metastases, PET-imaging status of intra-pelvic nodes must be known (positive or negative)
For patients with positive extra-pelvic metastases (defined as any PET positive lesions outside of standard salvage RT fields [prostate bed +/- typical whole pelvis]), the number of extra-pelvic lesions must be known (=< 5 or > 5 pelvic lesions)

Exclusion Criteria:

Patient must not have started androgen deprivation therapy for biochemical recurrence prior to baseline study PET/CT imaging
Patient must not be enrolled in another therapeutic clinical trial
Patient must not have any other malignancy within the last 2 years, other than superficial bladder cancer and skin basal cell carcinoma or cutaneous superficial squamous cell carcinoma that has not metastasized
Patient must not have history of seizures or known condition that may cause predisposal to seizures (e.g., stroke or head trauma resulting in loss of consciousness) within 1 year of registration
Patient must not have history of inflammatory bowel disease as this would increase risk of complication from radiotherapy or any gastrointestinal disorder affecting absorption
Patient must not have had prior radiation therapy