Current opinion in general surgery最新文献

This paper reviews studies on fecal occult blood testing and sigmoidoscopy screening for colorectal cancer. Recently published data from a randomized controlled trial provides the first concrete evidence that annual screening for fecal occult blood can reduce colorectal cancer mortality by at least 33%. These results are corroborated by a nonrandomized but controlled study that showed a 43% colorectal cancer mortality reduction with early detection through fecal occult blood testing and sigmoidoscopy, and by a case-control study that showed a 31% colorectal cancer mortality reduction associated with fecal occult blood testing. Persuasive data to support screening recommendations for sigmoidoscopy are not yet available; however, results from observational studies are suggestive and should stimulate further research to assess the benefit of sigmoidoscopy screening.

Over the past 30 years, numerous major centers have published analyses of potential factors influencing survival following resection of gastric cancer. The independent significance of depth of tumor penetration and lymph node status has been consistently documented. With proper staging, we know which patients are most likely to die of their disease. Unfortunately, adjuvant treatment in surgical resection has not altered patient outcome. Emphasis should now be on selecting the patients who should receive radical surgery for cure, adjuvant therapy with a hope for cure, or palliation. This brief review concentrates on recent developments in our ability to stage patients preoperatively, developments that may change the way we approach the patient with stomach cancer in the future.

Duodenal gastrinomas are now more frequently recognized as the source of hypergastrinemia in patients with Zollinger-Ellison syndrome. The cell lineage of duodenal gastrinomas may differ from that of pancreatic gastrinomas, which accounts for variations in their clinical behavior. Attempts to localize the submucosal tumors are difficult and are limited by their small size. Intraoperative endoscopic transillumination, selective intra-arterial secretin injection, and duodenotomy with mucosal eversion are currently the most sensitive and reliable methods of localization. Endoscopic ultrasonography and somatostatin scintigraphy further enhance the accuracy of preoperative localization of these tumors. Current information based on cure rates and survival data mandates a primary surgical approach in patients with either the sporadic or the multiple endocrine neoplasia type 1-associated form of the disease. Thus, wide local resection of duodenal gastrinomas with removal of all tumor-bearing lymphatic tissue and acid inhibitory pharmacotherapy (proton pump inhibition) may yield 5-year survival rates of 80% to 90%. Similarly, in patients with pancreatic and duodenal gastrinomas as a manifestation of multiple endocrine neoplasia type 1, the additional enucleation of pancreatic lesions with or without distal pancreatectomy has resulted in cure rates of 67% to 100%.

The utility of renal revascularization to control hypertension secondary to renal artery occlusive disease is widely recognized. However, revascularization for purposes of renal salvage, although performed successfully in many instances, is a more difficult issue, owing to the higher morbidity and mortality rates associated with operative intervention in an older patient population with significant comorbid conditions. It is therefore imperative to appropriately select patients who may benefit from revascularization, and the aim of our discussion is to aid in this selection process.

The goals of pancreatic transplantation are to improve the quality of life for the diabetic patient, reverse the metabolic abnormalities of diabetes, and prevent the dreaded secondary complications. Although transplantation of the whole pancreas is the only therapy that reliably achieves euglycemia, the complications associated with this procedure and the need for immunosuppression make it undesirable except to a select subpopulation of type I diabetic patients. Islet cell transplantation is the exciting alternative; however, insulin independence has been achieved in only 10% to 20% of patients. Although advances in technology could make islet transplantation the treatment of choice for type I diabetic patients, islet transplantation currently remains an experimental procedure. Diabetes is not commonly considered a surgical disease, but surgeons have made major contributions to its treatment and must remain active in the development of new treatment modalities for this debilitating disease.

The survival rate of patients with carcinoma of the esophagus is dismal. Improvement could be achieved only by earlier diagnosis and radical resection techniques to remove the esophagus and its draining lymphatic bed. En bloc esophagectomy and esophagectomy with three-field lymph node dissection are practiced in some centers in North America, Europe, and Japan. Survival rates with these techniques are better than those obtained with standard resection techniques.

Pancreatic endocrine tumors are rare, yet can cause significant morbidity due to excessive secretion of hormones. Octreotide is effective in reducing the plasma concentrations of many of these hormones. The availability of potent H2-receptor antagonists and omeprazole has altered the emphasis in patients with Zollinger-Ellison syndrome away from total gastrectomy and towards resection of the gastrinoma for potential cure. Fifty percent of insulinomas and gastrinomas are not evident on preoperative imaging studies, despite their sophistication. Calcium angiography, endoscopic ultrasonography, isotope-labeled octreotide scanning, and injection of methylene blue during secretin angiography are recent imaging modalities that have shown promise in the localization of these tumors. Intraoperative ultrasound has emerged as the best method for operative detection of insulinomas. Duodenotomy and intraoperative endoscopic transillumination are especially important in the surgical management of Zollinger-Ellison syndrome because 30% to 40% of gastrinomas are located in the duodenum. The management of patients with multiple endocrine neoplasia type 1 and Zollinger-Ellison syndrome continues to be controversial. Some advocate an aggressive surgical approach, whereas others have had little success in rendering patients eugastrinemic.

Modern advances in equipment and techniques have made it possible to treat many esophageal diseases with minimally invasive techniques. This chapter describes the impact of thoracoscopy and laparoscopy on esophageal surgery, with particular emphasis on the technique and results of esophageal myotomy, antireflux operations, and esophageal resection.