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51.

Background

Treatment of esophageal adenocarcinoma often involves surgical resection. Newer technologies in interventional endoscopy have led to a substantial paradigm shift in the management of early-stage neoplasia in Barrett’s esophagus comprising high-grade dysplasia (HGD), intramucosal carcinoma, and, in some cases, submucosal carcinoma. However, there has been no consensus regarding the indications for esophageal preservation in these cases. In this work, consensus guidelines were established for the management of early-stage esophageal neoplasia considering clinically relevant aspects (age, comorbidities, and social environment) in each scenario.

Methods

Seventeen experts were invited to participate based on their background and clinical expertise at high-volume centers. A questionnaire was created that included four clinical scenarios covering a wide range of situations within HGD and/or early esophageal neoplasia, particularly where controversies are likely to exist. Each of the clinical scenarios was open to discussion subdivided by patient age (20, 50, and 80 s). For each clinical scenario an expert was chosen to defend that position. Each defense triggered a subsequent discussion during a consensus meeting. Conclusions of that discussion together with an accompanying literature analysis allowed experts to confirm or change their original choices and served as the basis for the recommendations stated in this article.

Results

There was 100 % consensus supporting esophageal preservation in patients with HGD, independent of patient age or Barrett’s length. In patients with T1a adenocarcinoma, consensus for preservation was not reached (65 %) for young and middle-aged individuals but was supported for elderly patients (100 %). For T1b adenocarcinoma, consensus was reached for surgical resection (90 %), leaving organ preservation for patients with very low risk of nodal invasion or poor surgical candidates.

Conclusion

Advances in endoscopic imaging and therapy allow for organ preservation in most settings of early-stage neoplasia of the esophagus, provided that the patient understands the implications of this decision.  相似文献   
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Estrogen deficiency causes reduction of bone mass and abnormal bone microarchitecture, consequently reducing bone strength. Human parathyroid hormone (hPTH) (1-34) increases bone mass and strength. To clarify the factors that determine the recovery of bone strength in the lumbar vertebrae of ovariectomized rats by intermittent hPTH administration, we analyzed the relationship between skeletal measurements and bone strength. Human PTH (1-34) administration resulted in recovery of cortical bone mineral content (BMC) and cortical bone area to sham the levels, but in resulted in a less pronounced recovery of trabecular BMC and no increase in the total cross-sectional area of the vertebral body. Of the three-dimensional (3D) trabecular bone parameters, hPTH (1-34) increased trabecular thickness (Tb.Th). The cortical shell area of L4, determined by histomorphometry, was also increased. In hPTH-treated rats, the only determinant of the compressive load of L5 was the cortical shell BMC, in the early recovery period (days 42–84). Our data suggest that increased cortical bone mass contributes more than trabecular bone mass and structure to the recovery of bone strength in response to hPTH therapy in the rat lumbar vertebral body after ovariectomy.  相似文献   
55.
Lymph node metastasis in T1 adenocarcinoma of the colon and rectum   总被引:11,自引:0,他引:11  
The biology of colorectal cancer differs according to location within the large intestine. To evaluate the clinical significance of tumor location as a risk factor for lymph node metastasis (LNM), we performed a detailed pathological review of T1 adenocarcinomas of the colon and rectum. T1 adenocarcinomas of the colon and rectum treated by radical resection (n = 428) were identified from prospective clinical databases at two institutions. Tumor location was assigned as right colon (cecum to transverse), left colon (splenic flexure to sigmoid), or rectum (0–18 cm from AV). Pathology slides were reviewed, extent of submucosal invasion (sm width, sm depth) was quantified using an optical micrometer, and morphologic features of the cancer and its infiltrating margin were recorded. The overall rate of LNM was 10%. On univariate analysis, LNM was significantly more common in the rectum (27/176, 15%) compared to the left colon (13/160, 8%, p = .04) or right colon (3/92, 3%, p = .003). However, on multivariate analysis, deep submucosal invasion and lymphovascular invasion were independent and significant risk factors, whereas tumor location was not. T1 colorectal cancers have a progressively higher risk of LNM as their location becomes more distal. However, the increasing rate of LNM observed in cancers of the left colon and rectum is explained by a higher prevalence of high-risk pathologic features. In early colorectal cancers, tumor morphology is the strongest clinical predictor of metastatic behavior. Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004 Presented at the Forty-Fifth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, Louisiana, May 15–19, 2004  相似文献   
56.
We report two cases of osteoblastoma, one of them an unusual case in a 32-year-old woman in whom a maxillary tumor was confidently diagnosed as an osteoblastoma at the time of primary excision and subsequently transformed into an osteosarcoma 7 years after the onset of clinical symptoms. The other patient developed osteosarcoma arising in the maxilla, which was diagnosed 3 years after the primary excision and is very suggestive of malignant transformation in osteoblastoma. We present the radiological features, including computed tomographic and magnetic resonance imaging studies, of this unusual event of transformed tumor and compare imaging features of benign and dedifferentiated counterparts of this rare tumor complex.Members of the Group for the Image Diagnosis of Craniofacial Disorders  相似文献   
57.
Influence of luminal Ca2+ on the integrity of normal mucosa and recovery of damaged mucosa in anesthetized rat stomachs was studied using a perfusion system. Changes in the mucosal integrity were monitored by measuring transmucosal potential difference (PD) and luminal pH. EDTA, a Ca2+ chelator, dose-dependently reduced PD and increased luminal pH. Five mM Ca2+ (CaCl2) alone produced no changes in either PD and luminal pH, but the PD which was reduced by 250 mM EDTA was significantly recovered. Ethanol or NaCl concentration-dependently reduced PD, but gradually reverted to baseline levels. While 5 mM Ca2+ or 5 mM EDTA did not influence the reduction in PD with 50% ethanol or 1 M NaCl, these agents either enhanced or delayed the recovery processes in reduced PD, respectively. Five mM Ca2+ enhanced the recovery of PD which was reduced by 50% ethanol plus 5 mM EDTA. Gastric damage induced by 50% ethanol plus 5 mM EDTA was much more severe than that induced by 50% ethanol alone or 50% ethanol plus 5 mM Ca2+. Both 50% ethanol and 1 M NaCl significantly increased Ca2+ contents in the gastric lumen. Luminal Ca2+ appears to play an important role in maintaining mucosal integrity, under normal physiological conditions, and in accelerating the recovery process of damaged mucosa in rat stomachs.  相似文献   
58.
Situs inversus totalis is a rare congenital anomaly in which the major abdominal organs are located as a mirror image of their normal positions. This poses much difficulty for surgeons. We describe how we performed the liver-hanging maneuver (LHM) for hepatocellular carcinoma (HCC) in a 59-year-old man with situs inversus totalis, to resolve the difficulty of the mirror-image location of his liver. The HCC was located in the right lateral sector. Although segmentectomy of segment 7 would normally be considered minimal for a curative treatment of HCC, this was relatively complicated in this patient. Thus, we performed an extended right lateral sectionectomy using the LHM to achieve a simple transection. The hepatic hilum was dissected using the Glissonean pedicle transection method. The operation time and intraoperative blood loss were 6 h 45 min and 471 ml, respectively. No blood product transfusion was required. The LHM and the hilar Glissonean pedicle approach proved effective for resolving the difficulties of performing surgery in a mirror image for HCC in a patient with situs inversus totalis.  相似文献   
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Thoracic disc herniation is less common rather than cervical or lumbar herniation. Cases of sudden onset without trauma are especially rare. Generally, the neurological onset of disc herniation is caused by mechanical cord compression due to a protruded disc, and its onset is usually gradual. Ischemia is also considered as a factor of neurological onset. We report a case of a 78-year-old male with sudden paraplegia while straining at the toilet. T2 weighted MR image on admission showed mild disc protrusion at the level of Th8-9 and intramedullary high signal intensity below the Th8-9 level. We speculate that Valsalva-like maneuver had led to the congestion of vertebral venous plexus or compression of the anterior spinal artery, and spinal ischemia occurred.  相似文献   
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