Comparison of dynamic contrast-enhanced-magnetic resonance imaging parameters and serum markers in preoperative rectal cancer evaluation: Combined diagnostic value.

BACKGROUND

Rectal cancer requires accurate preoperative assessment of T stage and differentiation grade for treatment planning. Traditional imaging and serum markers have limitations in diagnostic accuracy.

AIM

To evaluate the predictive value of dynamic contrast-enhanced-magnetic resonance imaging (DCE-MRI) parameters and serum biomarkers [carbohydrate antigen (CA) 19-9, CA125] for determining T stage and differentiation grade in rectal cancer.

METHODS

We conducted a retrospective review of clinical data from 126 patients who were pathologically diagnosed with rectal cancer between January 2021 to June 2024. Each patient underwent DCE-MRI scans and serum tests for CA19-9 and CA125. Receiver operating characteristic curves were utilized to assess the diagnostic value of DCE-MRI parameters, including volume transfer constant (Ktrans), rate constant (Kep), and volume fraction of extravascular extracellular space (Ve), as well as serum biomarkers for staging and grading rectal cancer. The DeLong test algorithm was employed to evaluate differences in diagnostic performance among the various indicators.

RESULTS

There were statistically higher levels of Ktrans, Ve, CA19-9, and CA125 serum concentrations of patients with advanced T stages and on poorly differentiated tumors than that in patients with low stages and moderate to high differentiation ( < 0.05). Combined use of Ktrans and Ve for T stage diagnosis showed an area under the curve (AUC) of 0.892 [95% confidence interval (CI): 0.832-0.952], which increased to 0.923 (95%CI: 0.865-0.981) when combined with serum biomarkers. For grades differentiation, the combined DCE-MRI parameters had an AUC of 0.883 (95%CI: 0.821-0.945), which rose to 0.912 (95%CI: 0.855-0.969) when combined with serum markers. According to the Delong test, the combined diagnostic method performed better than a single diagnostic method ( < 0.05).

CONCLUSION

The combined application of DCE-MRI functional parameters and serum tumor markers can significantly improve the diagnostic accuracy of T staging and differentiation degree of rectal cancer, providing a new approach to improve the preoperative assessment system of rectal cancer. This combined diagnostic model has important clinical application value, but further validation is needed through large-scale multicenter studies.