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81.

Purpose

Gastrointestinal stromal tumors (GISTs) should be surgically resected, even those smaller than 5?cm in size, which is the threshold of clinical malignancy for submucosal tumors (SMTs) in the gastrointestinal tract. This study reviewed the use of laparoscopic surgery for gastric partial resection of GISTs or SMTs that were suspected to be GISTs.

Methods

Eighteen patients underwent laparoscopic partial resection of the stomach for GISTs or SMTs. The tumor location was confirmed by intraluminal endoscopy. One-half of the circumference around the tumor was dissected, and the tumor was turned toward the abdominal cavity. The nonresected part of the tumor and the edge of the incision line was lifted up using forceps, and the incision line was closed using laparoscopic stapling devices.

Results

Two cases were diagnosed as GIST by endoscopic biopsy. Six patients underwent endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) examinations, which diagnosed five GISTs. There were 18 tumors smaller than 5?cm, including 10 GISTs, 4 leiomyomas, 3 schwannomas, and one heterotopic pancreas.

Conclusions

Endoscopic ultrasound-guided FNAB is recommended for definite preoperative diagnosis of histopathologically unknown SMTs to determine the indications for surgery. The laparoscopic approach with the assistance of endoscopy is useful for improving the curability, with minimal invasiveness for the partial resection of GISTs.  相似文献   
82.
83.
Abstract Background: Advances in percutaneous coronary intervention (PCI) using drug‐eluting stents (DES) have impacted clinical practice. However, the efficacy of DES for dialysis patients still remains controversial. This study compares the early and long‐term clinical outcomes of coronary artery bypass grafting (CABG) and PCI with DES in dialysis patients. Methods: A retrospective review was performed in 125 dialysis patients treated between 2004 and 2007. Fifty‐eight patients underwent CABG and 67 underwent PCI with DES. The overall death, cardiac death, and cardiac‐related event rates were analyzed using the Kaplan‐Meier method. For the risk‐adjusted comparisons, multivariable logistic and Cox regression analyses were used. Results: The preoperative characteristics of the patients were similar except for the ejection fraction (p = 0.002) and the number of diseased vessels (p < 0.001). The 30‐day mortality was 0 in both groups. The overall survival rates at one, three, and five years were 84.2%, 64.7%, and 56.2% in CABG group and 88.2%, 75.5%, and 61.7% in DES group, respectively (p = 0.202). The rates of freedom from cardiac‐related events at one, three, and five years were 76.6%, 68.1%, and 48.6%, and 63.0%, 31.4%, and 0% in CABG and DES groups (p < 0.001), respectively, including seven (10%) late thromboses in the DES group. Although the risk‐adjusted analysis showed no significant difference for overall and cardiac death rates, the rates of cardiac‐related events and graft/stent failure were significantly higher in the DES group. Conclusions: CABG is superior for revascularization in dialysis patients compared with PCI using DES in terms of freedom from cardiac‐related events. (J Card Surg 2012;27:281‐287)  相似文献   
84.
H+/peptide transporter, PEPT1, is functionally expressed in some human cancer cell lines and might be a candidate molecular target for detection of cancers in vivo using PET. The aim of the present study was to establish a novel tumor-imaging technology using a PET tracer targeted to H+/peptide transporter(s). We also compared the tracer with 18F-FDG, focusing on the specificity of their accumulation between tumor and inflammatory tissues. METHODS: A dipeptide PET tracer, 11C-glycylsarcosine (11C-Gly-Sar), was injected intravenously into athymic mice transplanted with human pancreatic, prostate, and gastric cancer cells. The distribution patterns of 11C-Gly-Sar and 18F-FDG in the tumor-bearing mice, and in mice with inflammatory tissue, were assessed by imaging with a positron planar imaging system (PPIS). Tissue distributions of tracer radioactivity were also measured. The expression levels of PEPT1 and PEPT2 (PEPTs) proteins in tumor xenografts and inflammatory tissue were examined by immunohistochemical analysis. The messenger RNA expression levels of PEPTs in 58 available cancer cell lines were quantified by means of real-time polymerase chain reaction. RESULTS: All 3 tumor xenografts were well visualized with the PPIS after injection of 11C-Gly-Sar. Expression of PEPTs in those xenografts was confirmed by immunohistochemical analysis. Tumor-to-blood concentration ratios of 11C-Gly-Sar increased in a time-dependent manner and were much higher than unity. Most of the radioactivity found in the tumor tissue was recovered as the intact tracer. These results indicated that 11C-Gly-Sar was taken up by the PEPTs in tumor xenografts. It is noteworthy that 11C-Gly-Sar was minimally present in inflammatory tissues that expressed no PEPT1 or PEPT2 protein, whereas 18F-FDG was highly accumulated, with the values of the selectivity index being >25.1 and 0.72 for 11C-Gly-Sar and 18F-FDG, respectively. The mRNAs of PEPT1 and PEPT2 were expressed in 27.6% and 93.1%, respectively, of the cancer cell lines examined in the present study. CONCLUSION: The present study indicates that 11C-Gly-Sar is a promising tumor-imaging agent and is superior to 18F-FDG for distinguishing between tumors and inflammatory tissue. Because PEPTs were ubiquitously expressed in various types of tumor cells examined, 11C-Gly-Sar could be useful for the detection of many types of cancers.  相似文献   
85.
PURPOSE: The volar region of the scapholunate interosseous ligament is one of the key structures that maintains scapholunate alignment. It is, however, difficult to evaluate this ligament using standard diagnostic procedures, including the arthroscopy through a dorsal portal. We have performed arthroscopic evaluation of this ligament through a volar portal. METHODS: Skin incision was made at just radial of the flexor carpi radialis tendon and the portal was opened through the tendon sheath. RESULTS: The volar approach enabled us to directly observe the extent of the tear of the volar region of scapholunate interosseous ligament. A shaver is inserted through the dorsal portal, and debridement can be performed by using the volar portal vein. We have not had any complications using volar portal. CONCLUSION: Volar approach is a feasible and safe procedure to evaluate and treat the volar region of the scapholunate interosseous ligament.  相似文献   
86.
A 65-year-old man was admitted to our hospital for treatment of a squamous cell carcinoma in his right lung. Respiratory function testing showed an extremely reduced forced expiratory volume in 1 second (FEV1) of 1.0 l (29.9% of predicted), and a reduced FEV1/FVC ratio of 24.1%. Arterial blood gases on room air showed a pH of 7.41, a PaCO(2) of 36.7 mmHg, and a PaO(2) of 79.3 mmHg. To assess the predictive postoperative cardiopulmonary function, unilateral pulmonary artery occlusion (UPAO) testing was performed. In the condition of right main PA occlusion, the mean pulmonary artery pressure (mPAP), cardiac index (CI) and total pulmonary vessel resistance index (TPVRI) was 18 mmHg, 3.2 l/min/m(2) and 443.37 dyne.sec.cm(-5)/m(2), respectively. He underwent a middle lobectomy with combined partial resection of both the upper and lower lobes. He also underwent simultaneous resection of a giant bulla arising from the right upper lobe as lung volume reduction surgery. At 80 days after the operation, his FEV1 rose to 1.88 l, and the PaO(2) on room air was improved to 88.9 mmHg. UPAO testing was suggested to be more useful than routine pulmonary function test to determine the accurate predictive postoperative cardiopulmonary function and to decide indication for a radical operation.  相似文献   
87.
Aortoesophageal fistula (AEF) secondary to thoracic aneurysm is rare, and is usually fatal without prompt surgical intervention, with few survivors reported. Here we report a case of a 68-year-old woman late-presenting AEF successfully treated by extra-anatomic bypass grafting. Since she had already a mediastinal infection caused by AEF on admission, we performed extra-anatomic bypass grafting from the ascending aorta to the infrarenal aorta, and primary esophageal repair. The extra-anatomic bypass grafting was performed to avoid the risk to secondary graft infection and to decrease the total ishemic time induced by intraoperative aortic clamping, which is necessary when in-situ graft replacement is chosen. Although only 17 cases (including the present case) have been reported as long-term survivors, most have involved in-situ repair of the thoracic aneurysm. To our knowledge, the present case was only the second treated successfully by extra-anatomic bypass grafting. We recommend extra-anatomic bypass grafting for a case with severe infection and prolonged hypoperfusion insult caused by massive bleeding due to rupture in an aneurysm.  相似文献   
88.
The double stapling technique (DST) is an intestinal reconstruction technique that has been widely adopted in anterior resection (AR) for rectal cancer. However, anastomotic leakage (AL) after the operation remains a major concern for colorectal surgeons. The sharp-angled corner of the remnant rectum that is often created by the ordinary DST can be a risk factor for AL. We have developed a new method of performing intentional oblique transection DST (IOT-DST). Using this technique, the anal side of the rectum is intentionally obliquely transected with linear staplers, and the area of the sharp-angled edge is totally punched out with a circular stapler. Between September 2015 and March 2016, we used the IOT-DST technique in the treatment of 15 consecutive rectal cancer patients and experienced no anastomosis-related complications, including leakage and stenosis. IOT-DST is easy to use and less stressful to perform than other techniques. IOT-DST has the potential to become the standard technique for AR in rectal cancer surgery.  相似文献   
89.

Purpose

The clinical implications of mucinous components in rectal tumors, especially with regard to the efficacy of neoadjuvant chemoradiotherapy, remain unclear.

Methods

One hundred and thirty rectal cancer patients who received curative resection after neoadjuvant chemoradiotherapy were retrospectively reviewed. Patients were classified into 3 groups according to the proportion of extracellular mucin: low (<5 %), moderate (5–25 %), and high (>25 %).

Results

There were 82 (63.1 %), 26 (20.0 %), and 22 (16.9 %) patients in the low, moderate, and high mucin groups, respectively. Patients with a high mucinous tumor component were significantly more likely to have an advanced tumor stage (p = 0.010) and a shorter disease-free (p = 0.002) and distant recurrence-free survivals (p < 0.001), whereas the mucinous tumor component showed no correlation with local recurrence (p = 0.101). A high mucinous component was also an independent predictive factor for a shorter disease-free survival (p = 0.041, hazard ratio = 2.56) and distant recurrence-free survival (p = 0.001, hazard ratio = 5.74) according to a multivariate analysis.

Conclusions

Because the mucinous components showed little correlation with local recurrence, mucinous cancer should not be a determining factor for chemoradiotherapy. However, the frequent occurrence of metachronous distant metastasis among patients with a high mucin component makes this a possible indicator for more robust postoperative adjuvant treatment and close surveillance of recurrence.
  相似文献   
90.
To evaluate the interaction between the MR signal intensity distribution pattern and bleb formation/ deformation of the aneurysmal dome, fifty cases of the unruptured cerebral aneurysms were investigated with the color-coded 3D MR angiography. Patterns were categorized into central-type, neck-type and peripheral-type according to the distribution of MR signals with low-, moderate- and high signal intensity areas. Imaging analysis revealed the significant relationship (P < 0.02) of the peripheral-type aneurysms to the bleb formation and deformation of the dome, compared with those of central- and neck-type. Additionally, peripheral-type signal intensity distribution pattern was shown with aneurysms harboring relatively large dome size and lateral-type growth including internal carotid aneurysms. Prospective analysis of intraaneurysmal flow pattern with the color-coded 3D MR angiography may provide patient-specific analysis of intraaneurysmal flow status in relation to the morphological change of the corresponding aneurysmal dome in the management of unruptured cerebral aneurysms.  相似文献   
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