RESUMO
Purpose: We explored the predictive effect of intratumor metabolic heterogeneity indices extracted from 18F-FDG PET/CT on recurrence in stage II/III colorectal cancer after radical surgery. Methods: A total of 140 stage II/III colorectal cancer patients who received preoperative 18F-FDG PET/CT and radical resection were enrolled. 18F-FDG traditional parameters including the maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) under different thresholds; heterogeneity indices including the coefficient of variation with SUV 2.5 as a threshold (CV2.5), CV40%, heterogeneity index-1 (HI-1) calculated by the fixed-threshold method, and HI-2 calculated by the percentage threshold method; and clinicopathological information were collected. We concluded that relationships exist between these data and patients' disease-free survival (DFS). Results: Regional lymph node status (P < 0.001), nerve invasion (P = 0.036), tumor thrombus (P = 0.005), and HI-1 (P = 0.010) exhibited significant differences between the relapse and non-relapse groups, while SUVmax, MTV2.5, MTV40%, TLG2.5, TLG40%, CV2.5, CV40%, HI-2, and other clinicopathological factors had no differences between the relapse and non-relapse groups. Multivariate analysis demonstrated that HI-1 (HR = 1.02, 1.00-1.04, P = 0.038), regional lymph node metastasis (HR = 2.95, 1.37-6.38, P = 0.006), and tumor thrombus status (HR = 2.37, 1.13-4.99, P = 0.022) were independent factors significantly related to DFS. Conclusion: HI-1, tumor thrombus status, and regional lymph node status could predict the recurrence of stage II/III colorectal cancer after radical resection and had an advantage over other 18F-FDG PET/CT conventional parameters and heterogeneity indices.