Association between serum tumor markers and diabetic nephropathy in type 2 diabetes patients: a cross-sectional survey in Western China.

Background: Diabetic nephropathy (DN) is a common and serious microvascular complication of type 2 diabetes mellitus (T2DM). However, there is limited clinical research on the use of tumor markers in DN, and the relationship between serum tumor markers and DN in T2DM patients is not well understood.

Purpose: This study seeks to examine the potential association between serum tumor biomarkers and DN in individuals with T2DM in Western China.

Methods: This cross-sectional study involved 620 T2DM patients, including 253 with DN and 367 without. Differences between the groups were analyzed using Student's t-test, Mann-Whitney U-test, and Pearson's Chi-squared test. Logistic regression assessed the link between serum tumor biomarkers and DN presence, while Spearman's correlation analyzed the relationship between these biomarkers and kidney damage indicators. The diagnostic efficacy of the biomarkers was evaluated through receiver operating characteristic (ROC) curve analysis.

Results: In patients with T2DM and DN, the serum levels of carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), cancer antigen 211 (CA211), cancer antigen 125 (CA125), cancer antigen 199 (CA199), and squamous cell carcinoma antigen (SCC) were significantly elevated compared to those in the non-DN group, while serum levels of pro-gastrin-releasing peptide (ProGRP) were lower than those in the DN group (P < 0.01). After adjusting for potential confounding variables, serum levels of CEA, CA199, and CA125 were found to be independently associated with DN in T2DM patients. The odds ratio (OR) for elevated CEA in relation to DN was 1.41 (95% confidence interval [CI]: 1.17-1.70), for elevated CA125 was 1.02 (95% CI: 1.005-1.036), and for elevated CA199 was 1.021 (95% CI: 1.010-1.032). In this study, the levels of CA125 and CA199 exhibited a negative correlation with estimated glomerular filtration rate (eGFR), with correlation coefficients of -0.16, and -0.089, respectively. Conversely, these biomarkers were positively correlated with albumin-to-creatinine ratio (ACR), with correlation coefficients of 0.56, 0.55, and 0.22, respectively, and with cystatin C levels, with correlation coefficients of 0.17, 0.23, and 0.07, respectively. ROC curve analysis showed that combining CEA, CA125, and CA199 improves the accuracy in distinguishing DN patients, with an AUC of 0.82 (95% CI: 0.79-0.86, P < 0.001).

Conclusions: This study shows that serum tumor markers (CEA, CA125, and CA199) are strongly linked to the presence of DN in type 2 diabetes patients, providing new insights into their role in DN and suggesting potential prevention strategies.

Clinical trial number: Not applicable.