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51.
Objective: The diagnosis of small-sized (2 cm or less) non-small cell lung cancer (NSCLC) has increased with the development of computed tomography (CT), whereas unexpected extensive multiple-level mediastinal involvement has been occasionally detected in this small-sized lung cancer. To establish the optimal surgical strategy, we retrospectively analyzed the clinicopathologic features, efficacy of preoperative investigations and lobe specific patterns of nodal spread in small-sized NSCLC with mediastinal involvement. Methods: Among 1550 resected lung cancer cases between 1981 and 2000, 267 (17.2%) had peripheral small-sized NSCLC. Of these, 29 patients (10.8%) with mediastinal lymph node involvement who underwent pulmonary resection and systematic nodal dissection were reviewed. Results: Among 29 patients, 27 patients (93.1%) were adenocarcinoma, and 51.7% (15/29) showed no lymph node enlargement on CT (cN0). Surgical pathology revealed multiple-level mediastinal involvement in 65.5% (19/29) of all patients and 60.0% (9/15) of cN0 patients. All of right upper lobe tumors (n=11) showed multiple-level involvement. Thallium-201 single photon emission computed tomography (201Tl-SPECT) was positive for increased focal uptake in the mediastinum in 72.7% (8/11) of patients. Conclusions: The vast majority of cases were adenocarcinoma, and two thirds of them showed multiple-level mediastinal involvement, even in cN0 patients. We thus recommend to perform systematic nodal dissection or meticulous sampling for accurate intrathoracic staging, especially for right upper lobe tumor. 201Tl-SPECT appears to be more sensitive preoperative investigation for mediastinal metastasis compared with CT scan.  相似文献   
52.

Background  

The aim of this study was to compare the prevalence of recurrent nodular goiter in the contralateral thyroid lobe among patients after unilateral thyroid lobectomy for unilateral multinodular goiter (MNG) receiving versus not receiving postoperative prophylactic levothyroxine (LT4) treatment.  相似文献   
53.
Immunosuppressants lead to generation of reactive oxygen species (ROS). Oxidative stress (OxS) can initiate chronic allograft nephropathy (CAN). The most active antioxidant enzymes, superoxide dysmutase (SOD) and catalase (CAT), are present in erythrocytes. Glutathione peroxidase (GPx) is produced in the proximal tubules of nephrons. Malonyldialdehyde (MDA) concentrations are a marker of OxS intensity in plasma. In vitro and animal model studies have shown increased or decreased OxS during treatment with tacrolimus (Tac) or cyclosporine (CyA). Results obtained in humans after solid organ transplantation have been contradictory, because of confounding factors such as ischemia-reperfusion injury, donor and recipient ages, endothelial injury, and comorbidity. The aim of this study was to assess the intensity of OxS among rats under chronic immunosuppression (IS) without a transplantation. We examined 49 male Wistar rats. IS started at 12 weeks of age was continued for 6 months: group I were controls (n = 7); group II, Tac + sirolimus (Rapamycin [Rapa]) + corticosteroids (CS; n = 6); group III, CyA + Rapa + CS (n = 4 of which 2 died); group IV, Rapa + mycophenolate mofetil (MMF) + CS (n = 6); group V, CyA + MMF + CS (n = 6); group VI, CsA + MMF + CS for 3 months followed by conversion to Rapa (n = 6); group VII, Tac + MMF + CS (n = 6 rats); and group VIII, Tac + MMF + CS for 3 months followed by conversion to Rapa (n = 6). The drug doses were as follows: Tac 4 mg/kg/d; MMF 20 mg/kg/d; CyA 5mg/kg/d; Rapa 0.5mg/kg/d; and CS 4 mg/kg/d. Multiple regression analysis revealed that all IS drugs decreased GPx activity (P < .001) except CS, which increased it (P < .0001). Multiple regression analysis showed that CsA and Tac decreased plasma MDA concentrations (P < .01), whereas CS increased them (P < .05). In conclusion, all IS drugs except CS damage proximal tubules of nephrons.  相似文献   
54.
The authors have treated 13 cases of primary obstructive megaureter (POM) in children, presenting without vesicoureteric reflux. The diagnostic possibilities and the surgical approach options are discussed. Both Cohen and Leadbetter--Politano uretero-vesical reimplantation techniques proved to be successful in this series. Ureteric folding was done in 2 cases. Reported final results are good in 10 cases.  相似文献   
55.
OBJECTIVE: We retrospectively reviewed nodal status of the patients with peripheral small-sized lung cancer grouped by cell type and tumor size to evaluate the necessity of systematic nodal dissection in this group of patients. METHODS: From 1973 to 1998, 1713 patients underwent pulmonary resection for primary lung cancer in Kanazawa University. Among them, 225 patients (13.1%) with peripheral small-sized (2 cm or less) lung cancer underwent lobectomy and systematic nodal dissection were retrospectively reviewed. The maximum diameter of the tumor was measured on formalin-fixed surgical specimens. RESULTS: The histological types were adenocarcinoma in 170 (75.6%), squamous cell carcinoma in 20 (8.9%), small cell carcinoma in 19 (8.4%) and others in 16 (7.1%). Among 170 adenocarcinoma patients, 38 (22.4%) showed hilar or mediastinal lymph node metastases. No mediastinal lymph node metastasis was encountered in all squamous cell carcinoma (n = 20), adenocarcinoma < or = 1 cm (n = 16), small cell carcinoma < or = 1 cm (n = 4), and adenocarcinoma of Noguchi's classification type A or B (n = 24). CONCLUSIONS: Mediastinal nodal dissection would be unnecessary in the patients with peripheral small-sized lung cancer fulfilling these criteria: (1) squamous cell carcinoma < or = 2 cm; (2) adenocarcinoma < or = 1 cm; (3) localized bronchioloalveolar carcinoma < or = 2 cm without foci of active fibroblastic proliferation in histology (Noguchi's classification type A or B adenocarcinoma); (4) small cell carcinoma < or = 1 cm. Candidates fulfilling above criteria were 28.4% (64/225) of small-sized lung cancer and 10.9% of stage IA patients. The establishment of a universally accepted therapeutic strategy for small-sized lung cancer is indispensable in the clinical spread of various sort of limited resections.  相似文献   
56.
The purpose of this study was to evaluate the results of carinal resection for bronchogenic carcinoma in our institute. From 1981 to 1999, 24 carinal resection were performed for squamous cell carcinoma (n = 19), adenoid cystic carcinoma (n = 2), small cell carcinoma (n = 1), adenocarcinoma (n = 1), and mucoepidermoid carcinoma (n = 1). Nineteen underwent sleeve pneumonectomy, 2 had carinal resection without lung resection, 2 had carinal resection with right middle and lower lobectomy, and 1 had wedge pneumonectomy. In the patients with sleeve or wedge pneumonectomy, there were 5 operative death and 3 patients had survived for more than 3 years. Two patients with low-grade malignant tumors underwent carinal resection without lung resection and survived more than 10 years. We believe that limited carinal resection for low-grade malignant tumors are safe and valuable procedure. Careful selection of patients with sleeve or wedge pneumonectomy is mandatory.  相似文献   
57.

Background

Organ damage during organ procurement is believed to be an increasing problem among transplant centres. However, only very few published data are available. The purpose of our study was to examine the quality of kidney procurement in Germany.

Methods

We retrospectively analyzed all allograft renal transplants performed at our centre from 1996 to 2005. All kidneys were retrieved in Germany and allocated by Eurotransplant.

Results

From a total of 486 cadaveric kidneys, 103 (21.2%) were not correctly retrieved. Nevertheless, none of the organs had to be rejected. In 18 (3.7%), a technically insufficient organ retrieval was associated with a considerable extension of the surgical procedure or complications.

Conclusions

Technically insufficient kidney procurement rarely results in clinical consequences. However, surgeons performing organ retrieval should be better trained. Whether adequate technical proficiency is achieved with ten supervised cases, as requested by the German Medical Association, remains to be determined. In our opinion, a further interdisciplinary course that trains surgeons in more refined techniques of organ procurement is desirable.  相似文献   
58.

Background

Intragastric surgery is accepted as a minimally invasive procedure for mucosal or submucosal lesions. Robotic surgery promises to extend the capabilities of the minimally invasive surgeon and many surgical specialties are applying this new technology. However, there is no report of robotic intragastric surgery. We describe the use of the da Vinci® Surgical System for intraluminal mucosal resection of the stomach.

Methods

We developed our porcine intragastric surgery model using the Tuebingen MIS Trainer. We set a tentative lesion on the posterior wall near the esophagocardiac junction (ECJ) of the stomach and performed mucosal resection of the lesion using the da Vinci Surgical System. We also performed closure of the defect after mucosal resection and subsequent closure of the intentional gastric perforation.

Results

Using our porcine intragastric surgery model, we successfully performed mucosal resection of the tentative lesion. We also smoothly completed closure of the defect and closure of the perforation without any complications. The mean size of the mucosa was 6 cm and the mean duration of the procedure was only 12 min.

Conclusions

The safety and efficacy of robotic intragastric surgery was preliminarily established in this study. However, further studies are needed to prove its practical feasibility in humans using the da Vinci Surgical System to make it an effective operation.
  相似文献   
59.
OBJECTIVES: The objective of this study was to determine whether carcinoma in situ at the bile duct margin is prognostically different from residual invasive carcinoma in patients with extrahepatic cholangiocarcinoma. Although there are many reports that the ductal margin status at bile duct resection stumps is a prognostic indicator in patients with extrahepatic cholangiocarcinoma, some patients who undergo resection with microscopic tumor involvement of the bile duct margin survive longer than expected. METHODS: A retrospective clinicopathological analysis of 128 patients who had undergone surgical resection for extrahepatic cholangiocarcinoma was conducted. The status of the bile duct resection margin was classified as negative in 105 patients (82.0%), positive for carcinoma in situ in 12 patients (9.4%), and positive for invasive carcinoma in 11 patients (8.6%). RESULTS: Ductal margin status was an independent prognostic indicator by both univariate (p = 0.0022) and multivariate (p = 0.0105) analyses, along with lymph node metastasis. There was no significant difference between patients with a negative ductal margin and those with a positive ductal margin with carcinoma in situ (p = 0.5247). The 5-year survival rate of patients with a positive ductal margin with carcinoma in situ (22.2%) was significantly better (p = 0.0241) than with invasive carcinoma (0%). There was a significant relationship between local recurrence and ductal margin status (p = 0.0401). CONCLUSIONS: Among patients undergoing surgical resection for extrahepatic cholangiocarcinoma, invasive carcinoma at the ductal resection margins appears to have a significant relation to local recurrence and also a significant negative impact on survival, whereas residual carcinoma in situ does not. Discrimination whether carcinoma in situ or invasive carcinoma is present is important in clinical setting in which the resection margin at the ductal stump is positive.  相似文献   
60.

Background

Laparoscopic splenic vessel-preserving distal pancreatectomy (lap-SVPDP) is a popular procedure in pancreatic surgery. However, postoperative complications include false aneurysms of the splenic artery, splenic vein stenosis and thrombosis, pancreatic fistulas, abscess, and perigastric varices.

Methods

Eight patients (three men, five women, average age 66.1 years) with benign tumors underwent lap-SVPDP. Lap-SVPDP was performed in the lithotomy position with the head slightly elevated. The splenic vein was peeled longitudinally toward the pancreatic tail. A vessel-sealing system was used to detach the pancreatic body from the greater omentum, and the pancreas was transected using a surgical stapler.

Results

Mean operation time was 254 min; mean blood loss was 163 ml; and mean post-surgical hospitalization time was 13 days. No postoperative bleeding from the preserved splenic vessels occurred, and there were no splenic infarcts or splenic abscesses.

Conclusions

For safe performance of lap-SVPDP, the posterior surface of the pancreas should be completely exposed. The splenic vein should be ‘peeled away’, starting from its central rear, enabling easy detection of its course to avoid inadvertent sealing. With improved operational techniques, lap-SVPDP can be adopted as a standard procedure in pancreatic surgery.  相似文献   
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