Prostate Cancer Follow Up

Monitoring

Local Recurrence  

Initial PSA levels of ≥0.2 ng/mL and subsequent confirmatory levels of ≥0.2 ng/mL signify biochemical recurrence. Biochemical recurrence can be categorized as either of the following: 

• PSA level that fails to fall to undetectable levels post-radical prostatectomy (PSA persistence)
• PSA level undetectable post-radical prostatectomy but with ≥2 subsequent laboratory results with detectable PSA level or that increases to PSA >0.1 ng/mL (PSA recurrence)
• Persistent or low PSA levels due to slow PSA metabolism or residual benign tissue

Based on the Radiation Therapy Oncology Group – American Society for Therapeutic Radiology and Oncology (RTOG-ASTRO) Phoenix Consensus, PSA recurrence after EBRT with or without hormone therapy is defined as PSA increase of ≥2 ng/mL above the nadir PSA. Endorectal ultrasound may be considered to rule out recurrence after a radical prostatectomy. 

Follow-up Examinations  

PSA Monitoring  

PSA levels should be significantly lower after radical prostatectomy, radiation therapy, cryotherapy, and other treatments. PSA monitoring should be done every 3-6 months for 5 years then every 6-12 months for 5 years, then annually. Asymptomatic patients do not require further imaging if PSA is stable.  

DRE  

The timing of DRE after EBRT or radical prostatectomy is annually or if there is any suspicion of recurrence.  

Bone Scan  

Bone scan may be done if with symptoms or PSA levels rise after local therapy. It should be performed every 6-12 months to monitor ADT and at 8-12 week-interval for patients with CRPC. Bone densitometry measurement by dual-energy x-ray absorptiometry (DEXA) scans should be obtained regularly especially in patients at high risk for skeletal side effects and for monitoring of treatment response to Denosumab or bisphosphonates.  

CT scan or MRI 

CT scan or MRI may be considered if the following occurs after radical prostatectomy:

• PSA levels still detectable (PSA persistence) 
• Previously undetectable PSA is suddenly detected (PSA recurrence)
• Recorded PSA increases in >2 PSA level examinations
• Increasing PSA or positive DRE after radical prostatectomy 

These may be done every 3-6 months for monitoring of patient’s response to treatment.    

A spinal MRI to detect cord compression is recommended in CRPC patients with vertebral metastases and neurological symptoms. For patients without any evidence of metastases, imaging studies such as C-11 choline PET/CT, PET/MRI, F-18 fluciclovine PET/CT, or PET/MRI may be requested for further soft tissue and bone evaluation. For further bone evaluation: F-18 sodium fluoride PET/CT or PET/MRI may be requested in patients without any evidence of metastases.

PET/CT Scan and PET/MRI  

These imaging modalities have comparable sensitivity and specificity with other FDA-approved imaging agents in detecting recurrences at lower PSA levels. The PSA level cut-off of Choline PET/CT is between 1-2 ng/mL and PSMA PET/CT is <1 ng/mL.  

PET/CT Scan or PET/MRI has good sensitivity in prostate cancer restaging. It is useful in identifying CRPC and in predicting response to therapy.  

Salvage Treatments  

Local salvage therapy options include salvage radical prostatectomy, HIFU, cryoablation, and brachytherapy. Salvage therapy is considered in patients with low comorbidity, life expectancy of at least 10 years, a presalvage therapy PSA level <10 ng/mL, an initial ISUP ≤3 initial clinical stage of T1/T2, and no lymph node involvement.  

Salvage radiotherapy is a treatment option for patients with increasing PSA levels after radical prostatectomy and no presence of distant metastasis. It should be given once biochemical recurrence has been confirmed. One may consider hormone therapy if PSA is 0.20 ng/mL postoperatively. The recommended doses for adjuvant or salvage post-prostatectomy radiotherapy are 64-72 Gy. Salvage brachytherapy (permanent low dose-rate or temporary high dose-rate) may be considered in patients with confirmed local recurrence after EBRT or brachytherapy.    

Primary salvage or adjuvant radiotherapy may be considered in patients with PSA recurrence post-radical prostatectomy if without distant metastases. Patients with pathological T3 prostate cancer, positive margin/s or seminal vesicle involvement may be given adjuvant radiotherapy, usually given within 1-year post-radical prostatectomy and after recovery from operative side effects. Patients with previously undetectable PSA that became detectable on two measurements or with persistently detectable PSA post-radical prostatectomy may be given salvage radiotherapy.  

Early salvage IMRT or VMAT with IGRT may be used for patients with 2 consecutive biochemical relapses after radical prostatectomy. Salvage radical prostatectomy, HIFU, or cryosurgical ablation may be used for patients with local recurrence after radiotherapy or cryotherapy. Salvage ADT alone may be considered in patients with proven or high suspicion of metastasis, symptomatic local disease, or biochemical relapse with rapid PSA doubling time. Salvage cryoablation of the prostate may be an alternative to salvage radical prostatectomy. Salvage HIFU may be used as an alternative option for radiation-recurrent prostate cancer.

Referral

Refer the patient and his family to facilities that can provide palliative care services that can assist both the patient and his family while dealing with prostate cancer. Referral to pain clinics or palliative care teams may also help in the symptomatic management of prostate cancer patients.