Prognostic comparison between osteoblastic and osteolytic metastases in prostate cancer

Over 80% of patients develop bone metastases in the advanced stages of prostate cancer, resulting in a poor prognosis. To date, no study has explored the relationship between the type of bone metastasis and patient outcomes. The objective of this study was to compare the clinical features and prognoses of patients with osteoblastic and osteolytic bone metastases. Among the 63 patients diagnosed with bone metastases from prostate cancer at our institution between May 2011 and September 2023, 51 were classified as having osteoblastic metastases and 12 as having osteolytic metastases based on imaging findings. Overall survival was analyzed using Kaplan-Meier survival curves, and differences between groups were assessed using the log-rank test. Clinical parameters were compared using the Mann-Whitney U test. Univariate and multivariate Cox proportional hazards analyses were conducted to identify the prognostic factors. No significant differences were observed between the osteoblastic and osteolytic groups in terms of clinical or laboratory parameters, except for a higher platelet count in the osteoblastic group (p = 0.0181). The five-year overall survival rate was significantly higher in the osteoblastic group than in the osteolytic group (49.5% vs. 30.0%, p = 0.0437), with median survival times of 59 months and 38.5 months, respectively. In both univariate and multivariate Cox analyses, the type of bone metastasis was the only factor significantly associated with increased hazard ratios. Patients with osteolytic bone metastases from prostate cancer have a markedly lower five-year overall survival than those with osteoblastic metastases.