Table 1:

Important biologic differences between patients with biochemically recurrent prostate cancer and metastatic castration–resistant prostate cancer

	Biochemically Recurrent Prostate Cancer	Metastatic Castration-Resistant Prostate Cancer
Testosterone levels	Normal physiologic levels	Castrate levels of testosterone
Predominant Sites of Disease	Lymph nodes (based on early PET imaging)	Bone
Tumor Burden	Minimal—not seen on conventional CT or Tc99 bone scan	Variable—but substantial enough to be seen on conventional imaging