Abstract
Background: The objective of this study was to establish simple and reliable predictive system for survival in patients with prostate cancer diagnosed as having bone metastasis on initial bone scintigraphy.
Patients and methods: Ninety-four prostate cancer patients with bone metastasis included in this study were sub-classified into two groups according to the patterns of bone metastasis based on the findings of initial bone scan; that is, 33 patients with ≥5 metastases and with metastases to the appendicular skeleton (group A) and 61 with <5 metastases or with metastases to the axial skeleton alone (group B). Several clinico-pathological factors were analyzed according to this bone metastasis patterns.
Results: There were no significant differences among these two groups in terms of age, Gleason score, serum prostate specific antigen (PSA), serum alkaline phosphatase and clinical stage, while nadir PSA value after androgen withdrawal therapy in group A was significantly higher than that in group B. Furthermore, the overall survival rate in group A was significantly lower than that in group B; however, multivariate analysis using Cox proportional hazards model showed that this classification system could not be an independent predictor of overall survival in prostate cancer patients with bone metastasis.
Conclusion: These findings suggest that, despite the absence of an independent significance, multiple metastases ≥5 lesions including the appendicular bone could be used as a useful indicator for poor prognosis in prostate cancer patients with bone metastasis. Therefore, careful follow-up and if appropriate, intensive treatment should be considered in cases demonstrating such findings on the initial bone scintigraphy.