Risk factors for tumor recurrence in patients with pT3N0M0 thoracic esophageal squamous cell carcinoma after esophagectomy.

OBJECTIVE: To analyze the factors contributing to recurrence in patients with pT3N0M0 thoracic esophageal squamous cell carcinoma (ESCC). METHODS: Patients with pT3N0M0 thoracic ESCC who underwent esophagectomy from January 2008 to December 2012 were included retrospectively. The last date of follow-up was 1 December 2016. Multivariate proportional hazard Cox models were used to identify factors associated with total (i.e., any) recurrence (TR), locoregional recurrence (LR), and distant metastasis (DM). RESULTS: A total of 692 patients were included. The median follow-up was 53 months (range: 3-107). The 3- and 5-year TR, LR, and DM rates were 35.8% and 41.0%, 28.7% and 32.1%, and 16.8% and 21.1%, respectively. The Cox analyses showed that the tumor location, number of dissected lymph nodes, and postoperative therapies were significantly associated with LR. The subgroup analysis showed that postoperative therapies could significantly decrease LR in the mediastinum but not in the neck and upper abdomen regions. CONCLUSIONS: The recurrence rate of pT3N0M0 thoracic ESCC patients was high, especially for LR in the mediastinum. Postoperative therapies can significantly reduce the incidence of mediastinal recurrence.

[Effect of perfusion CT scan on hepatic hemodynamic changes in rats with liver micrometastases].

BACKGROUND & OBJECTIVE: Hepatic metastases are common for patients with malignant tumors, especially for the gastrointestinal malignancies. Early diagnosis confers better prognosis. This study was designed to investigate the hepatic hemodynamic changes by multi-slice helical perfusion CT in rats with liver micrometastatases of Walker-256 tumor cells. METHODS: Liver micrometastatases were produced in 22 SD rats by injecting 2 x 10(7) Walker-256 cells into the spleens. The ten experimental control rats were injected with normal saline solution. Ten rats were randomized into empty self control group from the experimental group before injecting tumor cells, which were studied by CT perfusion technique before being injected tumor cells. The time-density curves of the aorta, portal vein, and liver were used to calculate liver perfusion parameters by gradient method designed for the dual blood supply. These liver perfusion parameters were hepatic arterial perfusion (HAP), portal vein perfusion (PVP), hepatic perfusion index (HPI) and total hepatic blood flow. All the parameters were compared between the groups. H&E staining method was used to confirm the micrometastases pathologically. RESULTS: In the experimental group, 19 rats were found with micrometastases, of which the diameter was 0.5 mm to 6.6 mm. HAP was (97.67+/-31.42) ml x min(-1) x (100 ml) (-1) in metastasis group, and (43.35+/-17.39)ml x min(-1) x (100 ml) (-1) in control group, and (40.77+/-18.91) ml x min(-1) x (100 ml) (-1) in empty self control group. PVP was (295.49+/-61.85) ml x min(-1) x (100 ml) (-1) in metastasis group, and (385.7+/-71.25) ml x min(-1) x (100 ml) (-1) in control group, and (362.73+/-78.56) ml x min(-1) x (100 ml) (-1) in empty self control group, It was found that the HAP was higher in the rats with micrometastases than in those of the empty control group and also those of control group (F=47.84, P<0.000,1). While the PVP was lower in the rats with micrometastases than in those of the two control groups (F=14.10, P<0.000,1). For the total hepatic blood flow, no significant difference was found among the three groups (F=1.39, P=0.255). CONCLUSION: Higher HAP and lower PVP was noted in the rats with micrometastases. Perfusion CT technique can be used to evaluate the hepatic hemodynamic changes and thus has a potential clinical value for early diagnosis of liver micrometastases.