Osteolytic or mixed bone metastasis is not uncommon in patients with high-risk prostate cancer

Abstract

PurposeOsteolytic or mixed bone metastases (BMs) are considered rare in prostate cancer (PCa). However, we hypothesized that they are not uncommon in high-risk PCa. This study aimed to compare the clinical and CT imaging characteristics of PCa by focusing on BMs among patients with Gleason score (GS) ≥ 8 (high-risk group) and those with GS ≤ 7 (intermediate-low-risk group). MethodsBetween 2014 and 2021, patients with pathologically proven PCa and no history of other malignancies were included. Clinical findings including age and prostate-specific antigen (PSA) were collected. CT imaging findings, including the types of BM and other metastases, were evaluated by two radiologists. The clinical and CT imaging findings were compared between the high- and intermediate-low-risk groups. ResultsPatients were classified into high-risk (n = 527) and intermediate-low-risk (n = 973) groups. Age at diagnosis (median: 71 [44–91] vs 69 [35–86] years, p < 0.0001), PSA (8.7 [0.01–15314.5] vs 5.8 [0.01–163.2] ng/mL, p < 0.0001), frequencies of BMs (osteoblastic: 47/527 [8.7%] vs 3/973 [0.3%]), osteolytic or mixed BM (19/527 [3.6%] vs 2/973 [0.2%]), lymph node metastases (76/527 [14.4%] vs 3/973 [0.3%]), and lung metastases (13/527 [2.5%] vs 0%) were significantly higher in the high-risk group than in the intermediate-low-risk group (all p < 0.0001). ConclusionsAge, PSA, and the frequencies of osteolytic or mixed BMs were significantly higher in the high-risk group than in the intermediate-low-risk group. This study highlights the importance of high-risk PCa in the differential diagnoses of osteolytic or mixed BMs.