Metastatic Prostate Cancer Patterns and Detection

Primary Metastatic Sites

The liver is a common site for metastasis, with hepatic metastases present in about 10.2% of metastatic cases, according to the American College of Radiology 2
Pulmonary metastases occur in approximately 9.1% of metastatic prostate cancer patients, with a prevalence of about 7% in castration-resistant prostate cancer trials, as reported by the Journal of Clinical Oncology 3
Adrenal metastases are less common but can be detected on imaging studies, as noted by the Journal of Clinical Oncology 4

The Prostate Cancer Clinical Trials Working Group 3 (PCWG3) defines five clinical subtypes based on pattern of spread, including locally recurrent disease, non-metastatic castration-resistant prostate cancer, nodal spread, bone disease, and visceral disease, as outlined by the Journal of Clinical Oncology 5
Non-metastatic castration-resistant prostate cancer is characterized by rising PSA with no detectable disease on imaging, according to the American College of Radiology 2

Bone metastases are best detected using bone scintigraphy, which may include SPECT for improved characterization, as recommended by the Journal of Clinical Oncology 5
Nodal and visceral metastases are typically assessed with contrast-enhanced CT scan of chest, abdomen, and pelvis using ≤5-mm axial slices, as suggested by the Journal of Clinical Oncology 5
Lung metastases can be detected using chest CT imaging, due to the relatively frequent occurrence of pulmonary metastases in castration-resistant prostate cancer, as reported by the Journal of Clinical Oncology 3
Liver metastases can be evaluated using CT, which is very accurate for assessment of hepatic involvement, according to the American College of Radiology 2

The presence of visceral metastases generally indicates more aggressive disease and poorer prognosis than bone-only metastases, as noted by the Journal of Clinical Oncology 4
Patients with castration-resistant prostate cancer and bone metastases have a median survival of <2 years, as reported by the American College of Radiology 2
Understanding the pattern of metastatic spread is prognostic and should guide imaging strategies and treatment decisions, as outlined by the Journal of Clinical Oncology 5

Bone metastases may paradoxically appear worse on imaging despite effective treatment, which can lead to false interpretation of disease progression, as noted by the Journal of Clinical Oncology 4
PSA may not be a reliable marker of disease status in patients on androgen deprivation therapy, making imaging crucial for monitoring, as reported by the American College of Radiology 2
For patients with known metastatic disease, follow-up imaging should include assessment of all previously identified sites of disease, as recommended by the Journal of Clinical Oncology 8