New aspects in the etiopathogenesis of colorectal cancer

The paper analyzes the examination of 240 patients with alleviating pulmonary tuberculosis (follow-up group 2) and provides clinical and social characteristics of this group of patients who had poor social factors, such as a social behaviour, alcoholism, unemployment, etc. Ninety one patients had various concomitant visceral diseases. During treatment of pulmonary tuberculosis, most patients developed profound residual changes. This all requires more thorough follow-up while performing seasonal drug regimens and other prophylactic measures in Group 2 patients.     

Endoscopic therapy of esophageal cancer

In the management of esophageal cancer, endoscopy has evolved from a tool used to provide biopsy confirmation of suspected tumor to an integral part of the staging and ongoing treatment of patients. Endoscopic ultrasound is currently the most accurate means for T and N staging. Improved endoscopic techniques like dye staining and aggressive biopsy protocols can identify very early stage tumors in high-risk groups and allow curative surgery. Patients with early-stage tumors who are not surgical candidates can also be treated with endoscopic mucosectomy, photodynamic therapy, or Nd:YAG laser and still have a chance of long-term cure. Palliation of advanced tumors remains the major role of endoscopy in patients with esophageal cancer. A variety of techniques have proven effective over the years, including dilatation, laser, and rigid prostheses. Newer developments like bipolar probes, injection therapy, photodynamic therapy, and brachytherapy offer potential applications. The development and continuing improvements in both coated and uncoated expandable metal stents have been perhaps the greatest recent advance in endoscopic palliation of malignant dysphagia and esophagorespiratory fistulas. With the increasing array of endoscopic treatments and palliative techniques, emphasis must be placed on considering functional status; tumor characteristics like stage, location, and shape; patient wishes; and local expertise in tailoring treatment plans for each situation.     

The role of neoadjuvant therapy in surgically resectable esophageal cancer

OBJECTIVE: To determine the effect of neoadjuvant therapy (NT) (preoperative chemotherapy, radiation therapy, or both) in surgically resectable esophageal cancer. DESIGN: A retrospective review over a 20-year period. SETTING: A tertiary academic medical center. PARTICIPANTS: All patients undergoing surgical resection for esophageal cancer (N = 316) over this time period. MAIN OUTCOME MEASURES: Perioperative morbidity and mortality, local and distant recurrences, and overall survival. RESULTS: Patients undergoing NT (n = 106) had prognostic factors similar to those treated with surgery alone (n = 210). No increase was noted in surgical morbidity with NT (anastomotic leaks, reoperation rates, complications, or extended hospital stays). Overall survival was not improved by NT (median survival, 14 months) except in the subset of patients (11/83) who responded completely (100% histological necrosis) to preoperative chemotherapy (median survival, 79.2 months; P < .02). Complete response to radiation therapy alone was not associated with improved survival. Partial necrosis of the primary tumor was seen in 13 (15%) of 83 patients but conferred no survival advantage. Complete response to preoperative chemotherapy was associated with squamous cell pathological features and excellent performance status as measured by preanesthesia evaluation. CONCLUSIONS: The addition of NT did not increase perioperative morbidity or mortality. Only the subset of patients who had a complete response to preoperative chemotherapy showed a survival advantage. Excellent performance status and squamous cell pathological features were associated with an increased chance of complete pathological response following preoperative chemotherapy.     

Prognostic factors in esophageal cancer

Clinical and pathologic factors relevant to the prognosis of esophageal cancer are reviewed in this article. Clinical factors discussed include endoscopic, radiologic, and surgical findings. The importance of Barrett's esophagus and the role of endoscopic screening in the diagnosis of dysplasia and the prevention of adenocarcinoma are evaluated. Pathologic factors include the traditional ones of tumor type, stage, and grade as well as newer tumor markers related to DNA content, rate of cell proliferation, oncogenes, and tumor suppressor genes.     

Glutathione S-transferases in esophageal cancer

Glutathione content and glutathione S-transferase enzyme activity as well as isoenzyme composition were studied in normal gastric cardia, normal squamous esophageal epithelium and corresponding malignant tumor of 10 patients with esophageal cancer. Mean values of glutathione (38 +/- 6 versus 36 +/- 12 nmol/mg protein) and glutathione S-transferase activity (532 +/- 44 versus 532 +/- 108 nmol/min mg protein) did not differ significantly between normal esophageal and tumor tissue. However, great individual differences exist. In two patients, glutathione S-transferase activity was much higher in the tumor (1081 and 1381 nmol/min mg protein) due to overexpression of class alpha, mu and pig glutathione S-transferases in one case, and of class mu and pi in the other case. In the other patients, glutathione S-transferase activity was equal (one case) or lower (seven cases) in the tumor. In normal gastric cardia glutathione content as well as glutathione S-transferase activity was significantly lower as compared to normal esophageal epithelium. In conclusion, in contrast to other gastrointestinal tumors, glutathione S-transferases are overexpressed in esophageal tumors in only a limited number of patients.     

Prognostic factors of esophageal cancer]

A number of molecules involved in the process of invasion and metastasis of cancer cells have been demonstrated as a biological prognostic parameter. In esophageal cancer, overexpression of the oncogenes (c-erbB, int-2/hst-1/cyclin D1, MDM2), altered expression of suppressor genes (p 16, DCC), and abnormal expression of adhesion molecules (E-cadherin, alpha-catenin) has been reported as markers of high malignant potential. Proliferation markers (Ki-67, AgNORs, PCNA) and angiogenetic factors (intratumoral microvessel density, VEGF) are also related to the prognosis of the patients with various cancers including esophageal cancer. Prognostic significance of p53 is still controversial. In addition to the clinicopathological parameters, combination of these biological markers would be important to predict the clinical outcome of the cases and to establish an individualized strategy of the treatment of each case according to the biological behavior of the cancer cells.     

The management of cervical esophageal cancer by head and neck surgeons

Aspergillosis became an important opportunistic mycosis during the last years, with a great variety of clinical manifestations. To contribute to the replenishing of this mycosis serodiagnosis, biologic reactives (antigens and antisera) were prepared from strains of the species Aspergillus niger, Aspergillus flavus and Aspergillus terreus for their use in immunoprecipitation assays. The reactives were assessed by double immunospreading versus a reference commercial system; satisfactory results were obtained, and this guarantees the widening of the aspergillosis serodiagnosis in the Mycology Laboratory of the "Pedro Kourí" the Tropical Medicine Institute (IPK) with important imports savings.     

Intra-aortic ultrasonography in advanced esophageal cancer

Bisphosphonates are a group of chemical substances which have been used in medicine for thirty years in the treatment of skeletal diseases and disorders of calcium metabolism. Bisphosphonates are derived from pyrophosphate by substitution of an O atom for a C atom. This structure makes possible a number of variants by changing the side-chains of the C atom. The basic P-C-P bond is very thermostabile and completely resistant to enzymatic hydrolysis. The basic biological property of bisphosphonates is inhibition of bone resorption but has not been completely elucidated so far. The prerequisite is the inhibitory action of bisphosphonates on osteoclast activity. The latter are inhibited only when they are in contact with bone surfaces which contain bisphosphonates. Another possible mechanism of action of bisphosphonates is their action on osteoblasts: osteoblasts produce local growth factors which inhibit osteoclasts and thus osteoresorption is inhibited. So far it is not exactly known whether the direct effect on osteoclasts, the indirect effect via osteoblasts or a combination of both are the most important effect of bisphosphonates on the resorption of bone.     

Total thoracic esophagectomy for esophageal cancer

BACKGROUND: Many current methods of esophageal resection have drawbacks that result in inadequate proximal resection, inadequate lymphadenectomy, and difficult gastric and splenic access. We describe a technique that allows reliable and safe access to the chest, abdomen, and neck. STUDY DESIGN: From 1988 to 1995, 113 patients (82 men; mean age 65.3 +/- 4.5 years) with carcinoma of the esophagus or esophagogastric junction (middle third in 34, lower third in 41, and cardia in 38) underwent total thoracic esophagectomy. The histology was adenocarcinoma in 71 (62.8%), squamous cell carcinoma in 32 (28.3%), and undifferentiated carcinoma in 10 (8.9%) of the patients; 57 tumors (50.5%) were stage III. The esophagus and stomach were mobilized through a left thoracoabdominal incision. After completion of the esophageal resection, the fundus of the stomach was sutured to the esophageal stump to allow later delivery of the stomach into the neck. The esophagogastric anastomosis was performed with continuous single-layer absorbable suture through a left oblique cervical incision. RESULTS: The mean duration of the operation was 309.2 +/- 47.9 minutes. Hospital stay ranged from 5 to 49 days (median, 12 days). The perioperative mortality rate was 4.4%. Anastomotic leak occurred in six patients (5.3%), one of whom died. The proximal resection margin was microscopically free of tumor in all cases, and with a minimum followup period of 18 months, there has been no anastomotic recurrence in any patient. Actuarial survival at 1 year was 63.4% +/- 4.9%, at 3 years 41.4% +/- 5.9%, and at 5 years 22.7% +/- 6.3%. CONCLUSIONS: Total thoracic esophagectomy through the left chest with a separate left cervical incision allows clear access to the esophagus and stomach and good tumor clearance. This procedure may be performed with a low rate of anastomotic leakage, a very low mortality rate, and no anastomotic tumor recurrence.     

Role thrombocytes in etiopathogenesis of ischemic stroke

This paper presents the most essential problems concerning the role of platelets in the genesis of ischaemic brain disease and their role in spreading of ischaemic focus. The role of platelets in atherogenesis and development of vascular abnormalities in arterial hypertension and diabetes mellitus was considered, and attention was paid to conditions concerned with the pathogenesis of ischaemic stroke such as presence of antiphospholipid antibodies and presence of large volume platelets, in which platelet activation plays essential role. Then it was shown that platelet hyperactivation occurs in acute phase of ischaemic stroke and mechanisms of destructive action of activated platelets on recent ischaemic focus in brain such as secretion of neurotoxins and blocking of microcirculation by platelet aggregates were discussed.     

Modern views on etiopathogenesis of Alzheimer's disease

The aetiology of Alzheimer's disease (AD) remains, despite vast progress, not fully understood. Four genes involved in the development of the disease have been identified. Three fully penetrant ones (the amyloid beta-protein precursor on chromosome 21, presenilin 1 on chromosome 14, and presenilin 2 on chromosome 1) lead to the development of relatively rare familial form of AD. Together, they account for about half of this early-onset form of the disease. One genetic risk factor--polipoprotein E-4--is associated with late-onset Alzheimer's disease while at least two others are proposed. None of these genes can be by now adopted for use as a diagnostic or predictive test for Alzheimer's disease. Apart from the above, some environmental factors are also implicated in pathogenesis of the disease with the amyloid cascade hypothesis being the most commonly accepted as central. In the presented paper we have critically reviewed a literature on etiopatogenesis of Alzheimer's disease and discussed some practical consequences of the progress in understanding the mechanism of the disease.     

Injuries in the etiopathogenesis of multiple sclerosis

An injury might derange the protective function of the blood-brain barrier, and thus it represents one of the possible pathogenetic factors in the demyelination of the neural axis. However, the effect of injury on the occurrence or deterioration of multiple sclerosis is still controversial. According to most authors, the importance of injury in individual cases of multiple sclerosis is undeniable, as well as the fact that injuries are factors of progression and deterioration of the disease, but never its cause. Consequently, injuries can cause only temporary disability, and not permanent. Nevertheless, the incidence of multiple sclerosis increases proportionally to the severity of injury. The length of the period from the occurrence of injury to possible demyelination is still not established. Studies and clinical reports point to the fact that in the evaluation of injury as a precipitating factor for the vulnerability of the blood-brain barrier, the severity of the injury is of greater importance than its site.     

Telomerase assay for diagnosis of esophageal cancer

Esophageal squamous cell carcinoma is one of the aggressive diseases that has poor outcome. Therefore it is appeared that early diagnosis is very important for improving its outcome. Iodine staining method is useful for detecting the abnormal squamous epithelium and unstaining lesions by iodine contain the early esophageal cancers. Recently, telomerase activity that provides an immortal capacity for the cells has been measured in many tissues. We measured the telomerase activity in the samples of unstaining lesion by iodine using a polymerase chain reaction-based assay and described the relation between telomerase activity and histopathological findings.     

Multiple chemical sensitivity: theories of etiopathogenesis

Preferences often fluctuate as a result of transient changes in hunger and other visceral states. When current decisions have delayed consequences, the preferences that should be relevant are those that will prevail when the consequences occur. However, consistent with the notion of an intrapersonal empathy gap (Loewenstein, 1996) we find that an individual's current state of appetite has a significant effect on choices that apply to the future. Participants in our study made advance choices between healthy and unhealthy snacks (i.e., fruit and junk food) that they would receive in 1 week when they were either hungry (late in the afternoon) or satisfied (immediately after lunch). In 1 week, at the appointed time, they made an immediate choice, an opportunity to change their advance choice. Our main predictions were strongly confirmed. First, advance choices were influenced by current hunger as well as future hunger: hungry participants chose more unhealthy snacks than did satisfied ones. Second, participants were dynamically inconsistent: they chose far more unhealthy snacks for immediate choice than for advance choice. An additional hypothesis related to gender differences was also confirmed. Copyright 1998 Academic Press.     

The roles of multimodality treatment and lymphadenectomy in the management of esophageal cancer

PURPOSE: To review the current status of multimodality treatment and lymphadenectomy in the management of esophageal cancer. DATA SOURCES: Literature review. STUDY SELECTION: Multimodality treatment and lymphadenectomy in esophageal cancer. DATA EXTRACTION: Results in research papers published selected by literature search. RESULTS: Numerous studies have been carried out attempting to define the roles of various neoadjuvant or adjuvant regimens in the treatment of esophageal cancer. These included the use of radiotherapy or chemotherapy alone or in different combinations, with or without surgical resection. Randomized trials have failed to show significant improvement compared with surgical resection alone, although downstaging of disease and benefits on subgroups of patients could be demonstrated. Whether the extent of resection can influence outcome was tested by varying the surgical approach, and by increasing the extent of lymphadenectomy. Although indirect evidence exists suggesting more extensive resection may improve long term prognosis, definitive proof is lacking. CONCLUSIONS: More well organized randomized controlled trials are needed to further elucidate the roles of these approaches in the treatment of esophageal cancer.