Diagnostic Value of 18F-FDG PET/CT Parameters Combined with Serum FOXM1 for Lymph Node Metastasis in Colorectal Cancer.

Objective: To evaluate the diagnostic value of maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) in 18F-FDG PET/CT combined with serum forkhead box protein M1 (FOXM1) for detecting lymph node metastasis (LNM) in colorectal cancer (CRC). Methods: A retrospective study was conducted on 107 CRC patients who underwent 18F-FDG PET/CT and serum FOXM1 testing, with postoperative pathology as the reference standard. Patients were divided into LNM-positive (n=52) and LNM-negative (n=55) groups. PET/CT metabolic parameters (SUVmax, TLG, MTV) and serum FOXM1 levels were compared, correlations were analyzed by Spearman's test, and receiver operating characteristic (ROC) curves were plotted to assess diagnostic efficacy. Results: SUVmax was significantly higher in LNM-negative patients, whereas TLG, MTV, and serum FOXM1 were higher in LNM-positive patients (all P<0.05). Serum FOXM1 showed negative correlation with SUVmax (r=-0.356) and positive correlation with TLG and MTV (r=0.564, 0.549). The combined model of SUVmax, TLG, MTV, and FOXM1 yielded the highest diagnostic performance (AUC=0.971, sensitivity=92.2%, specificity=94.3%). Conclusion: SUVmax, TLG, MTV, and FOXM1 are interrelated and, when combined, provide superior diagnostic value for CRC LNM, though validation in larger, multicenter cohorts is needed.