Workup/Staging

Question 1

What imaging modalities are commonly used for a metastatic workup?

Answer 1

The imaging modalities most commonly used for workup of suspected metastatic prostate cancer include whole body bone scan (technetium-99m bone scintigraphy), CT abdomen/pelvis with contrast, and chest imaging with a CXR or CT. X-ray radiographs or MRI should be used if bone scan findings are equivocal.

Question 2

How sensitive are bone scans and CT scans for the detection of mets following biochemical failure?

Answer 2

Bone scan and CT scan are rarely positive until PSA values exceed 30 ng/mL in the absence of prior ADT. These scans are also more likely to be positive with faster PSA velocities. (Cher ML et al., J Urol 1998; Kane CJ et al., Urology 2003)

Question 3

Is there a role for PET scans in the evaluation of metastatic prostate cancer?

Answer 3

PET imaging is an evolving diagnostic tool, and multiple PET modalities are currently under investigation. Fluciclovine (18F-FACBC) was recently approved by the FDA for the detection of recurrent prostate cancer in men with rising PSA following Sg or RT. Optimal test characteristics are observed at higher PSA values. Multiple prostate specific membrane antigen (PSMA) targeting PET agents (such as 68Ga-PSMA) are also currently under investigation and may enter routine prostate cancer evaluation in the future.

Question 4

Is there a role for prostate Bx after biochemical failure in pts initially treated with RT?

Answer 4

Based on an ASTRO consensus statement, prostate re-Bx should be considered if the pt is considering additional local (salvage) therapy and is >2 yrs after the completion of RT. (Cox JD et al., JCO 1999)