Sub-satisfactory stenting recanalization of severe vascular stenosis of the posterior circulation can significantly improve cerebral hemodynamic perfusion.

PURPOSE: To investigate the effect of sub-satisfactory stenting recanalization of severe vascular stenosis of the posterior circulation on cerebral hemodynamic perfusion. MATERIALS AND METHODS: Patients with severe vascular stenosis of the posterior circulation who had undergone three-dimensional cerebral angiography before and after stenting were retrospectively enrolled. Computational fluid dynamic (CFD) analysis of hemodynamic parameters at the stenosis, perforating branch, and normal arterial segments proximal and distal to the stenosis were performed. RESULTS: Sixty-two patients with basilar artery stenosis aged 60.9 ±â€¯9.6 years were enrolled, and stent angioplasty resulted in the reduction of stenosis degree from 85.3 ±â€¯7.2% before to 18.6 ±â€¯6.4% after stenting. After stenting, at the proximal normal artery, the total pressures had significantly (P < 0.05) decreased, whereas all the other parameters (WSS, cell Reynolds number, velocity, vorticity, turbulence intensity, turbulence kinetic energy and dissipation rate) had significantly (P < 0.05) increased. At the stenosis, all hemodynamic parameters had significantly decreased. At the stenosis perforating branch, the WSS, cell Reynolds number, velocity, and vorticity were all significantly decreased, and the total pressure, turbulence intensity, kinetic energy, and dissipation rate were all significantly increased. At the distal normal artery, the total flow pressure (perfusion pressure) and velocity were both significantly (P < 0.05) increased, and the total pressure, WSS, cell Reynolds number, vorticity, turbulence intensity, kinetic energy, and dissipation rate were all significantly (P < 0.05) decreased. The hemodynamic parameters after stenting were closer to those after virtual stenosis repair at all measurements. CONCLUSION: Sub-satisfactory recanalization has significantly restored the stenosis and improved the hemodynamic parameters near the stenosis and at the root of the perforating branch, thus significantly improving the cerebral perfusion, similar to the changes of hemodynamic status and cerebral perfusion after virtual removal of the vascular stenosis. This may indicate the good effect of sub-satisfactory stenting recanalization of the vascular stenosis at the posterior circulation.

Safety and efficacy of enterprise stenting for symptomatic atherosclerotic severe posterior circulation stenosis.

PURPOSE: To investigate the safety and efficacy of Enterprise stent angioplasty and risk factors for the prognoses in treating symptomatic severe posterior circulation atherosclerotic stenosis (SSPCAS). MATERIALS AND METHODS: Patients with SSPCAS who were treated with the Enterprise stent angioplasty were retrospectively enrolled. The clinical data, peri-procedural complications, postoperative residual stenosis, in-stent restenosis and recurrent stroke at follow-up were analyzed. RESULTS: 262 patients with 275 stenotic lesions treated with the Enterprise stent angioplasty were enrolled. The stenosis degree was reduced from 86.3 ± 6.2% before to 19.3 ± 5.4% after stenting. Complications occurred in 14 (5.3%) patients. Clinical follow-up was performed in 245 (93.51%) patients for 16.5 ± 7.3 months. During 1 year follow-up, 7 patients (2.9%) had recurrent symptoms, including 4 patients with stenting in the intracranial vertebral artery and 3 in the basilar artery. Imaging follow-up was conducted in 223 (85.11%) patients. In-stent restenosis was present in 35 patients (15.7%), with the restenosis rate of 26.4% (n = 23) in the intracranial vertebral artery, which was significantly (P < 0.001) greater than in the basilar artery (8.8%). Six patients (17.1%) with in-stent restenosis were symptomatic. The stenotic length was the only significant (P = 0.026 and 0.024, respectively) independent risk factor for 1 year stroke or death events and in-stent restenosis. CONCLUSION: The Enterprise stent can be safely and efficaciously applied in the treatment of symptomatic severe posterior circulation atherosclerotic stenosis, with a relatively low rate of in-stent restenosis and recurrent stroke within 1 year. The stenotic length was the only significant independent risk factor for 1 year stroke or death events and in-stent restenosis.

[Analysis of the therapeutic effect of esophagectomy with extended 2-field lymph node dissection for esophageal carcinoma].

OBJECTIVE: To summarize the surgical effect and clinical application value of esophagectomy with extended 2-field lymph node dissection for patients with esophageal carcinoma. METHODS: From June 1987 to December 2008, 1690 patients with esophageal cancer underwent esophagectomy with extended 2-field (thoracic and abdominal) dissection of lymph nodes. Patients with the middle and lower thoracic esophageal cancer underwent Ivor-Lewis esophagectomy, and patients with upper thoracic esophageal cancer underwent Akiyama esophagectomy. 2-field (thoracic and abdominal) lymph node metastases information and the 1, 3, 5, 10-year survival rates were analyzed retrospectively. RESULTS: Lymph node metastases were found in 713 patients. The lymph node metastases rate was 42.2% (713/1690).Thoracic lymph node metastasis rate was 39.3% (665/1690), among which in the right pleural apical para-tracheal triangle was 20.7% (349/1690), in the posterior upper mediastinum was 26.3% (444/1690), in the lower mediastinum was 18.2% (307/1690). Abdominal lymph node metastasis rate was 20.1% (339/1690). THE Postoperative complication rate was 16.4% (278/1690), among which the pulmonary complication rate ranking the first, was 43.6% (136/312). The operative mortality rate was 0.2%. The 1-year, 3-year, 5-year and 10-year survival rates were 88.2% (1388/1574), 63.5% (868/1367), 54.8% (705/1287) and 30.8% (232/754), respectively. The 5-year survival rate in patients without lymph node metastasis was 76.2% (448/588), but that in patients with lymph node metastases was 36.8% (257/669). CONCLUSION: The results of this study demonstrated that Ivor-Lewis and Akiyama esophagectomy with two-field lymph node dissection exposes the operation fields clearly and make radical lymphadenectomy thoroughly, especially the lymph nodes in the posterior upper mediastinum around the recurrent laryngeal nerve and in the right pleural apical para-tracheal triangle. It is essential that patients with esophageal carcinoma with lymph node metastases should undergo esophagectomy with extended 2-field dissection of lymph nodes. This can elevate the postoperative 5-year survival rate remarkably.

[Correlation of aberrant methylation of MGMT gene to MTHFR C677T genetic polymorphisms in esophageal squamous cell carcinoma].

BACKGROUND & OBJECTIVE: As one of the principal causes of gene inactivation, aberrant hypermethylation in the promoter of cancer-related genes has attracted more and more attention. However, such studies on esophageal cancer are still limited. This study was to investigate the association between aberrant hypermethylation of MGMT gene and clinical characteristics as well as MTHFR C677T genetic polymorphisms in esophageal squamous cell carcinoma in a Chinese population. METHODS: A molecular epidemiologic study was conducted at Yangzhong County, Jiangsu Province of China, on histologically confirmed esophageal squamous cell carcinoma patients who were operated in the People's Hospital of Yangzhong County between January 2005 and March 2006. Peripheral blood samples, esophageal cancer tissues and paracancerous normal tissues were collected. Methylation-specific polymerase chain reaction(MSP) was used to detect the CpG island methylation status of MGMT gene. Restrictive fragment length polymorphism (RFLP) technique was used to test polymorphisms of folate metabolism enzyme gene MTHFR. The association between methylation status of MGMT gene and clinical characteristics as well as MTHFR C677T polymorphisms were analyzed. RESULTS: Among 125 esophageal squamous cell carcinoma patients, the aberrant hypermethylation rate of MGMT gene was 27.2% in cancer tissues and 11.2% in paracancerous normal tissues. No hypermethylation was found in normal esophageal tissues from 10 healthy adult subjects. Methylation rate of MGMT gene in cancer tissues was significantly higher in the patients with lymph node metastasis than in those without lymph node metastasis (37.3% vs. 18.2%, P=0.017). No association was found between aberrant DNA methylation and selected factors including sex, age, tobacco smoking, alcohol drinking and green tea drinking. After adjusting by potential confounders, variant allele of MTHFR C677T was found to be associated with hypermethylation of MGMT gene. Compared with wild type CC, the odds ratio was 3.34 (95% CI: 1.07-10.39) for CT and 3.83 (95% CI: 1.13-12.94) for TT. CONCLUSION: Aberrant CpG island hypermethylation of MGMT gene is closely related with the genesis and progression of esophageal squamous cell carcinoma.

[Regulations and lymphadenectomy strategy of mediastinal and upper abdominal lymph node metastasis in thoracic esophageal carcinoma].

BACKGROUND & OBJECTIVE: Regional lymph node metastasis plays an important role in the prognosis of esophageal carcinoma. However, the range of lymph node dissection is still controversial. This study was to investigate the regulations of lymph node metastasis of thoracic esophageal carcinoma in the mediastinum and upper abdomen, and explore the rational lymphadenectomy with Ivor-Lewis procedure. METHODS: A total of 1 412 thoracic esophageal carcinoma patients underwent radical esophagectomy and mediastinal and abdominal lymphadenectomy by Ivor-Lewis procedure from 1990 to 2005 at Yangzhong People's Hospital; 517 of them underwent right para-trachea triangle field lymphadenectomy through the right pleural apical approach. The regulations of regional lymph node metastasis were analyzed. RESULTS: Of the 1,412 patients, 323 (22.88%) had postoperative complications, 2 (0.14%) died during hospitalization, and 547 (38.74%) had lymph node metastasis. The lymph node metastasis rates were 32.30% in the right para-trachea triangle, 18.43% in the upper mediastinum, 5.31% in the lower mediastinum, and 17.28% in the upper abdomen(P<0.001). Of the 13 916 resected lymph nodes, 2 662 (19.13%) were positive; the metastasis degree (positive lymph nodes/resected lymph modes) were 23.83% in the right para-trachea triangle, 18.92% in the upper mediastinum, 21.07% in the lower mediastinum, and 17.20% in the upper abdomen. For those patients with the cancer focuses in the upper, middle and lower segments of the esophagus, the lymph node metastasis rates were 40.59%, 36.97% and 44.35% (P=0.093), respectively, while the lymph node metastasis degree in these 3 fields were 19.60%, 18.35%, and 21.82%, respectively. Both the lymph node metastasis rate and degree were significantly higher in the patients at advanced stage than in the patients at early stage (46.56% vs. 7.75%, 21.82% vs. 4.01%, P<0.001). CONCLUSIONS: Regional lymph node metastasis, especially in the right para-trachea triangle and upper mediastinum, is a key factor for thoracic esophageal carcinoma. Ivor-Lewis esophagectomy with two-field lymph node dissection is a safe operation for thoracic esophageal carcinoma, and may increase the chances of complete resection.

[Right para-tracheal triangle lymphadenectomy for esophageal carcinoma].

OBJECTIVE: To investigate the incidence of lymph node metastasis (LNM) in the right para-tracheal triangle (RPT) of esophageal carcinoma patients and the technique of dissection. METHODS: On the top of double mediastinal and abdominal lymphadenectomy, 333 esophageal carcinoma patients received RPT lymphadenectomy through the right pleural apical approach from 1990 to 2001. RESULTS: In these 333 patients, the lymph node metastasis (LNM) rate in the RPT was 36.40%. A total of 457 nodes among 2 159 nodes removed gave a metastasis degree of 24.96%. The LNM rates in RPT for cervical, upper third, middle third, and lower third segments of esophagus were 66.67%, 45.45%, 34.19% and 15.79% (P < 0.05), while their respective metastasis degrees were 44.44%, 27.04%, 24.32% and 18.92% (P > 0.05). The frequency of positive nodes in the RPT for PTI, PT1, PT2, PT3 and PT4 was 0, 17.24%, 28.7%, 45.16% and 53.57%, while those of metastasis degree were 0, 8.77%, 17.62%, 33% and 41.17% (P < 0.01). The frequency of LNM in the RPT in papillary, erosive, patch-like and covert type of early tumor was 40%, 3.85%, 0 and 0 (P < 0.05), while those of the metastasis degree were 29.41%, 1.82%, 0 and 0 (P < 0.01). Higher rate of LNM in progressive stenotic esophageal carcinoma was observed compared with those of the other gross types (56.52%, P < 0.05), so was the degree (P < 0.01). The frequency of LNM in the RPT for mono-focal and multi-focal tumor was 34.98% and 70% without significant difference (P > 0.05), while the degree was 24.29% and 53.33% (P < 0.05). Postoperative complications were: leak (0.6%), and recurrent laryngeal nerve injury (1.2%). No injury of vein or infra-clavicular artery, tracheal damage or mortality occurred. CONCLUSION: 1. The lymph node metastasis from esophageal carcinoma has a tendency of wide spread and right para-tracheal triangle is an important region to be doomed. 2. With location, depth of tumor invasion and differentiation of tumor as major factors affecting LNM of esophageal carcinoma, dissection of this region should be paid more emphasis. 3. In early lesions, higher frequency of LNM in the RPT is found in papillary and erosive lesions than in the other macroscopic types. 4. Exposing the RPT, lymph node by dissection through a right pleural apical approach is very important and significant.