Background
Our objective was to investigate the effect of race and age on the distribution of prostate cancer (PCa) metastases.
Methods
Patients with metastatic PCa were abstracted from the National Inpatient Sample database (2008-2015).
Results
Of 6,963 patients with metastatic PCa, 3,881 (72.2%) were Caucasians and 1,494 (27.8%) were African-Americans (AA). Bone metastases were the commonest site of metastases in Caucasians and AAs (83.9 vs 87.0%), followed by distant lymph node metastases in Caucasians (13.9% of Caucasians vs 13.2% of AAs), liver metastases in AAs (13.8% of AAs vs 13.3% of Caucasians) and lung metastases in both Caucasians and AAs (9.3 vs 13.1%), respectively. No clinically meaningful differences were recorded in age and race analyses, except for lymph node metastases (61.1 to 23.4% in Caucasians vs 39.0 to 25.1% in AAs), which decreased with age. Specific single organ metastatic sites, outside of bone and lymph nodes, were low in both racial groups (≤2.1%). The rate of brain metastases was also rare in both racial groups ≤1.4%, regardless of other metastatic locations. Thoracic metastases, in absence of bone and abdominal metastases were present in 1.9% of Caucasians and AAs.
Conclusion
The most important finding according to age and race resided in rates of lymph node metastases. Conversely, all other racial and age-related differences were subtle. Nonetheless, they are important in the context of planning and/or design of clinical trials. Finally, brain (1.4%) and thoracic (1.9%) metastases affect few patients and routine brain and chest imaging may not be warranted.