Single-center study of the abnormal concentration of bone imaging agent and prostate cancer bone metastasis prediction model

Abstract

Objective: To investigate the relationship between total prostate specific antigen (TPSA), free prostate specific antigen/total prostate specific antigen [RAT (F/T)], Gleason score, other factors and the whole-body bone plane imaging which was used to evaluate the bone metastasis of prostate cancer (PCa), and the diagnostic value of the abnormal concentration of bone imaging agent for single lesion. Methods: A retrospective analysis of (99)Tc(m)-methylene diphosphonate ((99)Tc(m)-MDP) whole-body bone imaging data of 93 patients with confirmed PCa in The First Hospital of Shanxi Medical University from Jan 2018 to Jan 2019 was conducted. The bone metastasis was diagnosed by whole-body bone imaging. The factors related to PCa bone metastasis, including age, TPSA, RAT (F/T), Gleason score were analyzed by Chi-square test and logistic two-class regression. The optimal cut-off point of TPSA was defined by receiver operating characteristic (ROC) curve. The region of interest (ROI) technique was used to repeatedly delineate the lesion (T) and the background area (NT) outside the bone and calculate the abnormal concentration value of bone imaging agent (T-NT)/NT, and the ROC curve was used to determine its diagnostic value. Results: The result of Chi-square analysis showed that Gleason score, TPSA and RAT (F/T) were associated with bone metastasis (P<0.05). Logistic regression analysis showed that TPSA and RAT (F/T) were associated with bone metastasis (P<0.01). TPSA >92.82 ng/ml was the best diagnosis for bone metastasis, and the sensitivity and specificity were 77.1% and 81.0%, respectively. There were 320 sites of high concentration of imaging agents in the whole-body bone imaging of PCa patients (194 in the metastatic group and 126 in the non-metastasis group). The (T-NT)/NT in the bone metastasis group was 7.11±0.29, the non-bone metastasis group was 2.69±0.20. (T-NT)/NT >3.52 was the best diagnosis for bone metastasis of single lesion, and the sensitivity and specificity were 86.1% and 80.2%, respectively. Conclusions: Gleason score, RAT (F/T) and TPSA are important risk factors of PCa bone metastasis. TPSA >92.82 ng/ml is the most supportive diagnosis for PCa bone metastasis. The abnormal concentration of bone imaging agent >3.52 owns the best diagnosis effect for the single lesion of PCa.