Current opinion in general surgery最新文献

Effective therapy for soft tissue sarcoma of the extremities continues in its lengthy evolution from mandatory amputation or radical compartment resection to multimodality limb salvage procedures. This current approach typically includes preoperative neoadjuvant systemic chemotherapy, followed by negative margin surgical resection in conjunction with radiotherapy. The scope and functional outcome of these resections has been markedly enhanced by the application of microvascular-dependent free tissue transfer techniques. Because of the rarity of this tumor system, problems in soft tissue sarcoma receive proportionally less attention. Nonetheless, the past year has witnessed several important advances in this field, as is discussed.

Recent developments in the understanding of antigen processing and presentation and T-cell receptor recognition of antigens have immediate applications to the cellular immunotherapy of cancer. The specific antigens and processed peptide sequences responsible for T-cell recognition of some human melanomas have recently been identified. T cells with antitumor activity are undergoing genetic modification to improve their function and clinical efficacy. In addition, novel T-cell constructs are being created with chimeric T-cell receptors that confer new tumor reactivities to these lymphocytes. Current understanding of the basic processes involved in the immune recognition and destruction of tumors is allowing the manipulation of these processes to enhance experimental clinical therapies.

The incidence of colorectal cancer is increasing. Approximately 20% of patients present with untreatable, disseminated disease. The remaining 80% are generally treated by intended curative resection. Unfortunately, about 40% of the Dukes B2 and C patients will develop recurrent disease. Of these patients, about one third will develop hepatic metastases, one fifth pulmonary metastases, one fifth intra-abdominal metastases, one tenth retroperitoneal metastases, and one twentieth anastomotic recurrences. Rectal cancer patients may have pelvic recurrence rates as high as one third. Unfortunately, only about one fifth of the Dukes B2 and C patients will initially develop recurrences at only one site and are, thus, potentially curable. Indeed, when considering all colorectal cancer patients, resectable recurrences will be detected in the liver in only 2%, regional recurrences in about 10%, in the lungs in 2%, anastomotic recurrences in less than 1%, and in the ovaries in 1%. In general, long-term survival can be achieved in about 30% of these patients with salvage surgery. The goal of intensive follow-up programs has been to identify these sole site recurrences at an earlier, asymptomatic stage and thereby improve survival. Unfortunately this laudable goal has not been achieved. Intensive (and expensive) follow-up programs consistently achieve long-term survival in 0% to 4% of patients. Reliance on symptoms, however, achieves remarkably similar end results.(ABSTRACT TRUNCATED AT 250 WORDS)

The extent of surgical resection required in the optimal management of differentiated (papillary and follicular) thyroid carcinoma remains controversial. Arguments in favor of total thyroidectomy include the adequate treatment of tumor multifocality, reduction in local recurrence rates and anaplastic transformation, and creating a suitable environment for radioactive iodine scanning and treatment of metastases. The benefits of this procedure have to be weighed against the potential but minimal morbidity.

Nine articles published since January 1992 on new methods of evaluating hepatic function are reviewed. These articles described the clinical significance of blood levels of cytokines, fibrin- or fibrinogen-related antigens, vitronectin, and endothelin, and of magnetic resonance spectroscopy, methionine metabolism, vasopressin clearance, vascular compliance, and radioreceptor imaging in gastroenterology. None of the methods have yet been applied to surgery. In addition, the redox theory, the evaluation of hepatic mitochondrial redox potential by arterial ketone body ratio and its clinical application, is introduced, and recent publications on the assessment of graft viability in liver transplantation and preoperative hepatic functional reserve in liver surgery based on the theory are reviewed.

The ability to assign causative roles to Helicobacter pylori and nonsteroidal anti-inflammatory drug use in peptic ulcer disease, and proof that eradication of H. pylori infection results in cure of peptic ulcer disease, are resulting in a reassessment of the indications for surgery and the type of surgery to be performed. With only a few exceptions, surgery is rapidly becoming an outdated approach to the management of peptic ulcer disease. We will soon see the day when surgeons with great technical skill in peptic ulcer disease will be rare, just as it happened when chest surgeons were no longer needed for the management of chronic pulmonary infections.

Experimental studies demonstrate that angiotensin II and somatostatin analogues have some ability to redirect hepatic arterial blood flow toward liver metastases. Albumin microspheres and liposomes are both effective to animal models in enhancing intra-arterial drug delivery to tumor tissue. Clinical studies show that such strategies can also improve drug targeting in humans. Clinical trials of intrahepatic arterial chemotherapy demonstrate definite response and survival benefits, but toxicity can be considerable, and progression of extrahepatic disease remains an unsolved problem. Selective means of delivering radiation, biologic therapy, and thermal energy to liver metastases are possible alternative nonsurgical treatments that merit further investigation.

Recent publications dealing with pancreatic pseudocysts, pancreatic ascites, and pancreatic fistulas are reviewed. Terminology relevant to pancreatic pseudocysts and other complications of acute pancreatitis is clarified. The natural history of pseudocysts is examined. Newer management strategies for these complications of pancreatic inflammatory disease are discussed, including percutaneous drainage of pseudocysts and the use of octreotide in the management of pancreatic ascites and pancreatic fistulas.

New insights into the genetic changes associated with cancer, the genetic control of programmed cell death, and the availability of new tools to study biologic problems including targeted gene disruption and quantitative polymerase chain reaction have defined new questions and allowed more sophisticated answers in studies of fundamental cellular processes. The development of new approaches in the clinic, including nascent gene therapies, is rapidly evolving.