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Atypical lipomatous tumor or well-differentiated liposarcoma/dedifferentiated liposarcoma (DDLPS) is the most frequent subtype of malignant adipocytic tumor. This tumor typically presents in late adult life, most commonly in the retroperitoneum, extremities, or spermatic cord. It has been reported that the dedifferentiated component consists mainly of high-grade sarcoma, including undifferentiated pleomorphic sarcoma, fibrosarcoma, and myxofibrosarcoma, and it has been recently reported that the dedifferentiated component can be also made up of a low-grade sarcomatous component. Therefore, the dedifferentiated areas exhibit a wide morphological spectrum that commonly includes fibroblastic/myofibroblastic and fibrohistiocytic tumors but very rarely includes vascular tumors. We present here the first reported case of DDLPS with a hemangioendothelioma-like component in the spermatic cord.  相似文献   
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BACKGROUNDSchwannoma of the pancreas is extremely rare. We report a case of pancreatic schwannoma that was difficult to distinguish from pancreatic carcinoma before surgery.CASE SUMMARYA 66-year-old male underwent a right-lobe hepatectomy for hepatocellular carcinoma. Post-surgical computed tomography showed a 10 mm long solid mass with ischemia, with no expansion into the main pancreatic duct. Upon magnetic resonance cholangiopancreatography, the tumor had high signal intensity in diffusion weighted images, consistent with pancreatic carcinoma. Endoscopic ultrasound (EUS) was performed to obtain more information about the tumor, and showed a 14 mm solid and hypoechoic mass in the pancreatic body. Contrast enhanced EUS revealed that the tumor showed a hyperechoic mass in the early phase, and the contrasting effect continuation was very short; findings also consistent with pancreatic carcinoma. Thus, we preoperatively diagnosed his condition as a pancreatic carcinoma and performed distal pancreatectomy with splenectomy. Microscopic examination showed that the tumor was in fact a benign schwannoma. Histology showed a proliferation of spindle-shaped cell in a vague fascicular and haphazard pattern, with palisading arrangement.CONCLUSIONSchwannoma of the pancreas is very rare, however, clinicians should consider schwannoma as the differential diagnosis for pancreatic tumors.  相似文献   
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The double-stapling technique using a circular stapler (CS) to create an end-to-end anastomosis is currently used widely in laparoscopic-assisted rectal surgery. However, a high rate of anastomotic failure has been reported. We report new side-to-side anastomosis creation using a CS, the so-called circular side stapling technique (CST). After excising the rectum at the oral and anal sides of the tumor with a linear stapler, a side-to-side colorectal anastomosis was made on the anterior wall of the rectosigmoid colon and the anterior or posterior wall of the rectum with a CS. Between 2012 and 2013, we recorded 30 serial cases of rectal-sigmoid or rectal cancer that were treated with laparoscopic-assisted surgeries using this method. In the 30 cases, the mean age was 68 ± 12 years, operating time was 288 ± 80 minutes, and blood loss was 66 ± 67 mL. None of the patients suffered from anastomosis leakage or postoperative anastomotic bleeding, and none complained of their stool habits. Three months after the last surgery in this cohort, no anastomosis strictures were reported. Based on these results, we propose an alternative method of side-to-side anastomosis for low anterior resection by using a CS to prevent staple overlap. Our experience indicates that the CST is easy and safe. Therefore, this method is a useful alternative to the current method used in laparoscopic surgery.Key words: Laparoscopy, Circular stapler, Colorectal cancer, Low anterior resectionLaparoscopic surgery for the treatment of colorectal disease has proven to be a safe and effective method compared with an open procedure.13 Laparoscopy has the advantages of reduced blood loss, hospital stay, and use of anesthetics as well as a better cosmetic outcome. Although many clinical studies have demonstrated the advantages and low complication rates of laparoscopic colectomy and low anterior resection,15 a high rate of anastomotic leakage has been reported in laparoscopic rectal surgeries. The reported incidence of leakage after laparoscopic surgery for the treatment of rectum varies from 6% to 17%.13 Additionally, anastomotic leakage might raise concerns about local recurrence and may limit the patients prognosis.68 Therefore, despite great advances in laparoscopic surgery, the risks of anastomotic complications persist to a greater extent than those for other colonic resections.6,7Recent reports have included proposed methods for reducing anastomotic leakage, and recently a transanal drainage tube has been recommended, because the high pressure experienced in the rectum could cause anastomotic failure.9 Another group reported the use of anti-traction sutures supporting the anastomosis to reduce anastomotic leakage.10 Despite these proposals, anastomotic failure has not been completely resolved.In typical laparoscopic rectal surgery, a double-stapling technique (DST) with a circular stapler is used to create the anastomosis. This method is thought to be the only method available to complete an intracorporeal anastomosis of the rectum. However, the DST requires the excision of the stump of the staple line created by the linear stapler. Our previous endoscopic experience with anastomotic leakage shows that leakage occurs frequently at the point where the staples overlap in the DST.11 In this study we demonstrate a new circular side stapling technique (CST), which does not require the excision of the linear staple line in a laparoscopic low anterior resection.  相似文献   
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Many kinds of bone graft materials have been developed and reported to repair various bone defects. The defects are usually created by surgical resection of pre‐existing bone tissue. However, spontaneous healing of bone defects without implantation of materials could be seen, because bone tissue possesses inherent repairing property. The central portion of the lower jaw bone in many animals consists of fibrous tissue and is called the mandibular symphysis. It persists even in old animals and thus can be interpreted as a physiological bone gap or a non‐healing bone defect. We implanted calcium phosphate porous ceramics alone or composites of the ceramics and bone marrow stromal cells (BMSCs) into the bone defect (mandibular symphysis) to examine whether it could be filled with new bone tissue, resulting in bone union. Eight weeks after implantation, micro‐computed tomography (micro‐CT) and histological and biomechanical analyses demonstrated that bone union of the mandibles occurred in all rats with composites but in none of those with ceramics alone. These results showed that the rat mandibular symphysis is a unique bone defect site for the evaluation of bone graft materials. These analyses demonstrated that ceramics alone could not contribute to bone healing in the defect; however, supplementation with BMSCs drastically changed the properties of the ceramics (turning them into osteogenic ceramics), which completely healed the defect. As BMSCs can be culture‐expanded using small amounts of bone marrow, the use of the composites might have clinical significance for the reconstruction of various bone tissues, including facial bone. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Y Adachi  M Mori  Y Maehara  K Sugimachi 《Gut》1994,35(10):1368-1371
Dukes''s classification for colorectal cancer is simple, and correlates well with survival. This study assessed whether the principles of Dukes''s classification applied to gastric cancer resulted in the separation of prognostically useful groups. The cumulative survival curves determined by Dukes''s, Astler-Coller''s (another classification for colorectal cancer), and the Japanese classification for gastric cancer were evaluated using 476 curatively treated patients with gastric cancer. Of the three staging systems, both Dukes''s and the Japanese classifications showed a step-wise relationship between the stage of the tumour and the survival of patients. The prognostic value of Dukes''s classification was reinforced when Dukes''s C cases were subdivided according to the number of positive nodes (1-6 v > or = 7) or the level of positive nodes (n1 v n2,n3) but not when the subdivision was made according to the depth of wall invasion. A modified Dukes''s classification in which Dukes''s cases are subdivided according to the number of metastatic nodes (Dukes''s Ca = 1-6 nodes, Dukes''s Cb > 6 nodes) could be both simply and accurately applied to gastric cancer.  相似文献   
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