Texture analysis of (18)F-FDG PET/CT scans has the potential to differentiate between TET tumor grades; regional-scale indices from GLRLM and GLSZM perform better than local-scale indices from the NGTDM. The SUVmax and heterogeneity indices may have complementary value in differentiating TET subgroups.

Synchronous colorectal cancer liver metastasis (SCLM) remains a clinical challenge, largely because of the limited availability of tools that use reliable prognostic indicators to guide treatment. This study assessed the prognostic ability of preoperative 18 F-FDG PET/ CT in patients with SCLM who had undergone curative-intent colorectal and liver surgery. Methods: All included patients had undergone simultaneous colorectal and hepatic surgery to treat SCLM. Cox regression for survival analysis was undertaken using clinicopathologic variables and metabolic parameters (metabolic tumor volume [MTV], total lesion glycolysis [TLG], and peak standardized uptake value [SUV peak ]) as covariates, with tumor recurrence and death used as endpoints. Results: One hundred twenty patients (82 men, 38 women; mean age ± SD, 59.9 ± 10.1 y) met the inclusion and exclusion criteria. Univariate analysis showed that MTV, TLG, and the size of hepatic metastases were significant indicators of both recurrence-free survival and overall survival, whereas those of primary colorectal tumors were not. Multivariate analysis revealed that the SUV peak of primary tumors and hepatic metastases remained significant after adjusting for other clinicopathologic variables, whereas the MTV and TLG of hepatic metastases became insignificant after adjusting for differences in tumor size. The combination of a high SUV peak of hepatic metastases and a low SUV peak of primary tumors was related to poor prognosis under the multivariate model. Conclusion: In patients with SCLM who underwent curative-intent colorectal and liver surgery, metabolic parameters of hepatic metastases possess prognostic significance whereas those of primary colorectal tumors do not. For hepatic metastases, the SUV peak is an independent prognostic factor, whereas MTV and TLG are surrogate measures of tumor size. Reduced recurrencefree survival rates are associated with higher SUV peak for hepatic metastases and lower SUV peak for primary tumors. Further studies are needed to elucidate the underlying mechanisms. Col orectal cancer (CRC) accounts for much of the global morbidity and mortality associated with cancer, especially in developed countries. The liver is the single most common site of distant metastasis; up to 50% of CRC patients develop liver metastasis during the course of the disease, and 20%225% of patients with newly diagnosed CRC present with synchronous liver metastasis at the time of initial diagnosis (1-3).Hepatic metastasectomy is the standard of care to treat liver metastasis when curative surgery is feasible. However, the prognosis after hepatectomy is poor, with the 5-and 10-y survival rates after hepatectomy being approximately 40% and 25%, respectively (4). The prognosis is even poorer for patients with synchronous hepatic metastasis (a hepatic metastasis presented at the same time of its primary colorectal tumor) than for those with metachronous hepatic metastasis (a hepatic metastasis that has developed after the resection of the primary colorectal tumor) ...