Can PSA predict bone metastasis amongst newly diagnosed prostate cancer patients?

Abstract

Background: The decision as to when a bone scan is necessary in the staging of prostate cancer is controversial with different studies giving varying recommendations on the same subject. Objective: To determine the utility of total Prostate Specific Antigen in the prediction of bone metastases in newly diagnosed prostate cancer patients. Methods: This was a cross-sectional descriptive study carried out on newly diagnosed treatment naïve, prostate cancer patients over a period of five months. Patients who had an elevated prostate specific antigen of more than 10ng/ml, at least six core biopsies and bone scan examinations within one month of the PSA estimation were recruited. The bone scan results were then correlated with tPSA levels and Gleason scores from the histopathology report. Results: Of the 54 patients recruited, only 20% had positive bone scans. There was statistically significant association between bone scan results and Gleason scores (p value =< 0.001). The highest sensitivity and specificity was obtained at a PSA cut off of 100ng/ml, with area under curve of 0.7019. Conclusion: The results of this study show that PSA may be used in conjunction with Gleason scores as a predictor of the presence of bone metastases.