Predictive value of the pretreatment serum sialic acid/total protein ratio for bone metastases in newly diagnosed prostate cancer patients: development of a nomogram model.

Abstract

Background: Bone is a common site of distant metastasis, and its metastasis is one of the major causes of death in prostate cancer (PCa) patients. Currently, there is a lack of effective predictive methods. This study aimed to evaluate the potential of pretreatment serum sialic acid/total protein (SA/TP) ratio as a biomarker for predicting PCa and its associated bone metastases.

Methods: A retrospective analysis was conducted on 641 patients diagnosed with benign prostatic hyperplasia (BPH) or PCa between November 2014 and July 2021. We conducted a comparative analysis of SA/TP levels across various subgroups and investigated the correlation between SA/TP levels and multiple clinical parameters. Independent risk factors were identified through both univariate and multivariate logistic regression analyses, and a predictive model for assessing the risk of bone metastases was developed.

Results: PCa patients presented significantly higher median pretreatment SA/TP levels than BPH patients (P<0.001). Furthermore, within the cohort of PCa patients, individuals with bone metastases demonstrated markedly elevated pretreatment SA/TP levels in contrast to their counterparts without bone metastases (P<0.001). Additionally, receiver operating characteristic (ROC) curve analysis identified an optimal cut-off value of 0.7973 for distinguishing BPH from PCa, accompanied by an area under the curve (AUC) of 0.606 [95% confidence interval (CI): 0.559-0.653, P<0.001]. In parallel, the optimal cut-off value for differentiating between bone metastases and without bone metastases in PCa patients was identified as 0.8560 with an AUC of 0.770 (95% CI: 0.707-0.833, P<0.001). Multivariate logistic regression analysis revealed that a pretreatment SA/TP ≥0.7973 was independently correlated with PCa [hazard ratio (HR) =1.704, 95% CI: 1.016-2.806, P=0.04], whereas a pretreatment SA/TP ≥0.8560 served as an independent risk factor for PCa with bone metastases (HR =2.567, 95% CI: 1.051-6.271, P=0.04).

Conclusions: The elevated pretreatment SA/TP level is closely associated with the risk of PCa and its subsequent bone metastases.