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N Ectors

Publications and source records attributed to N Ectors.

At least 19 recordsLinked to original sources
PubMed2006

The effect of polyethylene glycol and butyrate on anastomotic healing in the rat colon.

BACKGROUND: The use of mechanical bowel preparation is much debated. METHODS: We evaluated the effects of polyethylene glycol (PEG), with or without a single dose of 3.0 mmol butyrate (BUT), on the bursting pressure (BP) of an intact colon segment and a colon anastomosis in rats. Also, histopathologic damage was studied. RESULTS: In rats without colectomy, the mean BP was 159.2 mmHg (SD=18.9) after PEG treatment and 116.7 mmHg (SD=27.5) in controls (p=0.001). In rats with colectomy, the mean BP was 90.4 mmHg (SD=45.9) in the PEG group, 108.0 mmHg (SD=31.9) in the BUT group, and 102.7 mmHg (SD=44.7) in controls (p=0.44). No significant differences in histopathologic scores were observed between rats treated with PEG and controls. CONCLUSIONS: PEG does not interfere with anastomotic healing in rats as measured by BP. No benefit of a single dose of butyrate was observed.

Administration, Oral↗
PubMed2006

A new approach to the validation of tissue microarrays.

Although tissue microarrays (TMA) have been widely used for a number of years, it is still not clear how many core biopsies should be taken to determine a reliable value for percentage positivity or how much heterogeneity in marker expression influences this number. The first aim of this study was to validate the human visual semi-quantitative scoring system for positive staining of tumour tissue with the exact values determined from computer-generated images. The second aim was to determine the minimum number of core biopsies needed to estimate percentage positivity reliably when the immunohistochemical staining pattern is heterogeneous and scored in a non-binary way. Tissue sections from ten colorectal cancer specimens were stained for carbonic anhydrase IX (CA IX). The staining patterns were digitized and 400 artificial computer-generated images were generated to test the accuracy of the human scoring system. To determine the minimal number of core biopsies needed to account for tumour heterogeneity, 50 (artificial) core biopsies per section were taken from the tumoural region of the ten digitally recorded full tissue sections. Based on the semi-quantitative scores from the 50 core biopsies per section, 2500 x n (n = 1-10 core biopsies) experimental core biopsies were then generated and scores recorded. After comparison with field-by-field analysis from the tumoural region of the whole tissue section, the number of core biopsies that need to be taken to minimize the influence of heterogeneity could be determined. In conclusion, visual scoring accurately estimated the percentage positivity and the percentage tumour present in a section, as judged by comparison with the artificial images. The exact number of core biopsies that has to be examined to determine tumour marker positivity using TMAs is affected by the degree of heterogeneity in the expression pattern of the protein, but for most purposes at least four is recommended.

Adenocarcinoma↗
PubMed2006

Validation of 16S rDNA sequencing in microdissected bowel biopsies from Crohn's disease patients to assess bacterial flora diversity.

The bowel flora is implicated in Crohn's disease (CD) pathogenesis but its precise role is still unclear. Several non-mutually exclusive hypotheses have been proposed: an unidentified persistent pathogen; excessive bacterial translocation; an immune system abnormality in response to normal bacteria; or a breakdown in the balance between protective and harmful bacteria. These hypotheses can be tested by identifying bacteria in specific microscopic bowel structures or lesions. The present paper describes a novel technique to assess bacterial flora diversity in bowel biopsies, by combining laser capture microdissection with broad-range 16S rDNA sequencing. Fifty-four samples comprising histologically normal and pathological mucosa, MALT, ulcers, submucosal lymphangiectasias, epithelioid granulomas, and lymph nodes were microdissected out of 30 bowel biopsies from five CD patients. Bacterial 16S rDNA was successfully amplified by PCR in all samples, and PCR products from 15 samples were selected for cloning and sequence analysis. A total of 729 bacterial DNA sequences were analysed, which could be attributed to six different phyla (Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Fusobacteria, and Planctomycetes). DNA from typical bowel bacteria (Enterobacteriaceae, Clostridiales, Bacteroidetes, Fusobacteria) was detected in all microdissected areas. It was thus convincingly demonstrated that 16S rDNA sequencing can be combined with microdissection to study the bowel flora. However, no specific persistent pathogen causal for CD was identified. The results suggest that Enterobacteriaceae may initiate or colonize ulcers in CD. Translocation of bacteria through established mucosal lesions or as a result of increased permeability may be involved in the evolution towards chronic inflammation and in the establishment of persistent lesions. Further study is needed to confirm these preliminary findings.

Adolescent↗
PubMed2006

Review article: the nature of oesophageal injury in gastro-oesophageal reflux disease.

The purpose of this review was to explore issues relating to the nature of oesophageal injury in gastro-oesophageal reflux disease. Several structural and functional elements of the oesophageal epithelium provide for an inherent resistance against refluxed material. It is only when this defence is overcome that reflux-induced damage ensues. The light microscopic changes in reflux oesophagitis are manifold. Early changes are confined to the epithelium and consist of reactive changes and inflammatory cell infiltration. When the epithelial integrity can no longer be maintained, erosions and ulcers develop. Recently, dilatation of the intercellular spaces was described as a sensitive early marker for gastro-oesophageal reflux disease. This parameter was first identified by electron microscopy but can also be assessed by light microscopy in routinely stained tissue sections. Some of the changes occurring in early gastro-oesophageal reflux disease can be reproduced by incubating oesophageal mucosal biopsies in gastrointestinal fluids or their components. Activated pepsin, trypsin and conjugated bile acids at an acidic pH have been identified as probable causes of reflux-induced damage.

Bile↗
PubMed2005

Chemo-radiotherapy versus radiotherapy alone in the pre-operative treatment of resectable rectal cancer.

AIM: To determine the differences in downstaging, local control (LC), disease free survival (DFS) and overall survival (OS) between combined pre-operative chemoradiation and pre-operative radiotherapy alone in the treatment of resectable rectal cancer. METHODS: One hundred and ten patients who underwent pre-operative radiotherapy or chemo-radiotherapy were reviewed. Fifty-seven patients were treated with radiotherapy (30 Gy/3 Gy) alone and 53 patients with chemo-radiotherapy (bolus 5FU+45 Gy/1.8 Gy). The median interval between the end of neo-adjuvant treatment and surgery was 28 and 46 days for the patients treated with radiotherapy alone and chemo-radiotherapy. RESULTS: The groups were homogeneously distributed for all characteristics except for cN-stage with more clinically node positive patients in the combined modality treatment group (47 vs 73%). A significant downstaging for tumour and/or lymph node status was observed in both groups. More ypT0-x-is were observed after chemoradiation than after radiotherapy alone (26 vs 7%; p=0.02). The local control rate at 3 years was 94% for both groups. DFS after radiation and chemoradiation was comparable with a 3-year DFS of 83 and 88%, respectively. CONCLUSION: Both pre-operative schemes have similar outcomes concerning DFS, OS and LC. Tumour downstaging is associated with improved survival.

Adenocarcinoma↗
PubMed2004

Identical cytokeratin expression pattern CK7+/CK20- in esophageal and cardiac cancer: etiopathological and clinical implications.

Surgical treatment and prognosis is different in esophageal, cardiac and distal gastric adenocarcinomas. Determination of the origin, in particular of adenocarcinomas situated at the gastroesophageal junction, may be difficult. It has been suggested that esophageal adenocarcinomas are characterized by a specific cytokeratin pattern, namely the CK7+/CK20- pattern. According to the same authors, this cytokeratin pattern is absent in gastric adenocarcinomas. The aim of our study is to evaluate if this cytokeratin pattern CK7+/CK20- is absent in cardiac and distal gastric adenocarcinomas. Therefore, we evaluated the combined immunohistochemical expression of CK7 and CK20 on paraffin-embedded material of 214 resection specimens for adenocarcinoma, comprising 66 esophageal, 73 cardiac and 75 distal gastric adenocarcinomas (UICC-classification). The adenocarcinomas were subtyped into intestinal- and diffuse-type according to the Lauren classification. The immunohistochemical staining was considered as positive if 50% or more of the tumor cells were stained. Statistical analysis has been performed applying the chi2-test. The tumors situated at the gastroesophageal junction, esophageal as well as cardiac adenocarcinomas, showed predominantly a CK7+/CK20- expression pattern (67 vs 68%), whereas this cytokeratin pattern is rather uncommon in distal gastric adenocarcinomas (31%, P<4 x 10(-5)). Independent of their localization, intestinal- as well as diffuse-type adenocarcinomas have a similar cytokeratin pattern. Our data show that the combined expression of CK7 and CK20 is different for the adenocarcinomas situated on both sides of the gastroesophageal junction compared to the distal gastric adenocarcinomas. However, in contrast to data in the literature, the combined expression of CK7 and CK20 has a low specificity in the distinction between esophageal and cardiac adenocarcinomas. This may suggest a similar origin (cell lineage) and thus may have an impact on therapeutic strategies.

Adenocarcinoma↗
PubMed2004

Gastro-intestinal stromal tumour of the duodenum: extreme presentation in two cases.

Gastro-intestinal stromal tumours (GIST) are primary mesenchymal tumours arising from the gastro-intestinal tract. They are uncommon visceral tumours, preferentially located in the stomach and small intestine. The present paper will discuss the clinical presentation of GIST in a 32-year-old female (Case 1) and in a 72-year-old female (Case 2). In both cases the tumour is located in the duodenum which appears to be a rather unusual location (4%) for GIST. This work will illustrate that duodenal GIST can occur in extreme presentations, diverging from vague complaints to directly life threatening symptoms.

Adult↗
PubMed2004

Three-field lymphadenectomy for carcinoma of the esophagus and gastroesophageal junction in 174 R0 resections: impact on staging, disease-free survival, and outcome: a plea for adaptation of TNM classification in upper-half esophageal carcinoma.

OBJECTIVE: To determine the impact of esophagectomy with 3-field lymphadenectomy on staging, disease-free survival, and 5-year survival in patients with carcinoma of the esophagus and gastroesophageal junction (GEJ). BACKGROUND: Esophagectomy with 3-field lymphadenectomy is mainly performed in Japan. Data from Western experience with 3-field lymphadenectomy are scarce and dealing with relatively small numbers. As a result, its role in the surgical practice of cancer of the esophagus and GEJ remains controversial. METHODS: Between 1991 and 1999, primary surgery with 3-field lymphadenectomy was performed in 192 patients, of whom a cohort of 174 R0 resections was used for further analysis. RESULTS: Hospital mortality of the whole series was 1.2%. Overall morbidity was 58%. Pulmonary complications occurred in 32.8%, cardiac dysrhythmias in 10.9%, and persistent recurrent nerve problems in 2.6%. pTNM staging was as follows: stage 0, 0.6%; stage I, 9.2%; stage II, 27.6%; stage III, 28.7%; and stage IV, 33.9%. Overall 3- and 5-year survival was 51% and 41.9%, respectively. The 3- and 5-year disease-free survival was 51.4% and 46.3%, respectively. Locoregional lymph node recurrence was 5.2%; no patient developed an isolated cervical lymph node recurrence. Five-year survival for node-negative patients was 80.2% versus 24.5% for node-positive patients. Five-year survival by stage was 100% in stages 0 and I, 59.1% in stage II, 36.8% in stage III, and 13.3% in stage IV. Twenty-three percent of the patients with adenocarcinoma (25.8% distal third and 17.6% GEJ) and 25% of the patients with squamous cell carcinoma (26.2% middle third) had positive cervical nodes resulting in a change of pTNM staging specifically related to the unforeseen cervical lymph node involvement in 12%. Cervical lymph node involvement was unforeseen in 75.6% of patients with cervical nodes at pathologic examinations. Five-year survival for patients with positive cervical nodes was 27.7% for middle third squamous cell carcinoma. For distal third adenocarcinomas, 4-year survival was 35.7% and 5-year survival 11.9%. No GEJ adenocarcinoma with positive cervical nodes survived for 5 years. CONCLUSIONS: Esophagectomy with 3-field lymph node dissection can be performed with low mortality and acceptable morbidity. The prevalence of involved cervical nodes is high, regardless of the type and location of tumor resulting in a change of final staging specifically related to the cervical field in 12% of this series. Overall 5-year and disease-free survival after R0 resection of 41.9% and 46.3%, respectively, may indicate a real survival benefit. A 5-year survival of 27.2% in patients with positive cervical nodes in middle third carcinomas indicates that these nodes should be considered as regional (N1) rather than distant metastasis (M1b) in middle third carcinomas. These patients seem to benefit from a 3-field lymphadenectomy. The role of 3-field lymphadenectomy in distal third adenocarcinoma remains investigational.

Adenocarcinoma↗
PubMed2003

[Weight loss, joint pain and abdominal lymphadenopathy as signs of sarcoidosis, but also of Whipple's disease].

Two patients, a woman aged 66 and a man aged 56 years, with an inflammatory syndrome, weight loss, joint pain and abdominal lymphadenopathy received long-term treatment with corticosteroids for alleged sarcoidosis. No long-term remission was induced and the patients were referred for a second opinion. Eventually the diagnosis of Whipple's disease was established 5 years after the appearance of the first symptoms in the case of the female patient and 4 years after in the case of the male patient. Both patients showed a marked clinical improvement after treatment with trimethoprim-sulfamethoxazole. An atypical presentation of alleged sarcoidosis should suggest the possibility of Whipple's disease, especially in the case of gastrointestinal symptoms and the failure to respond to corticosteroids, and warrants duodenal biopsy. The presence of granulomas with an elevated angiotensin-converting enzyme level is not pathognomonic for sarcoidosis. It is vitally important to distinguish the two disorders, as Whipple's disease is an infectious disorder that requires antibiotic therapy to prevent a fatal outcome.

Abdomen↗
PubMed2003

Extracapsular lymph node involvement is a negative prognostic factor in T3 adenocarcinoma of the distal esophagus and gastroesophageal junction.

OBJECTIVE: To assess prognosis according to whether lymph node involvement is intracapsular or with extracapsular breakthrough in adenocarcinoma of the distal esophagus and gastroesophageal junction. Materials and methods One hundred ninety-five consecutive patients with T3 adenocarcinoma of the distal esophagus and gastroesophageal junction between 1990 and 1999 were studied. All patients underwent primary R0 esophagectomy. The mean number of resected nodes per patient was 36.9. Survival was analyzed according to intracapsular and extracapsular involvement. RESULTS: In N0 patients 5-year survival was 57% and 9-year survival was 38.7%. In patients with positive nodes these figures were 26.2% and 18.1%, respectively (P =.0069). Intracapsular and extracapsular node involvement showed 5- and 10-year survival of 40.9% and 21.7% versus 18% and 15.7%, respectively. There was no significant difference in 5- and 10-year survival between N0 and intracapsular node involvement (P =.43). However, there was a significant difference in survival between N0 and extracapsular node involvement (P =.002) and between intracapsular and extracapsular node involvement (P =.0001). CONCLUSIONS: This study shows a significant difference in survival according to whether lymph node involvement was intracapsular or extracapsular. Patients with intracapsular lymph node involvement have similar survival rates as N0 patients. Extracapsular lymph node involvement is a bad prognostic factor, independent of the number of involved lymph nodes. The number of involved lymph nodes has an additive negative effect. These data may have an impact on treatment strategies.

Adenocarcinoma↗
PubMed2003

Are carcinomas of the cardia oesophageal or gastric adenocarcinomas?

There is a clear relationship between Barrett's oesophagus and oesophageal adenocarcinoma, and between Helicobacter pylori and gastric cancer, but the histogenesis of cardiac adenocarcinomas is unknown. Some clues as to possible disease associations may be provided by the pattern of gastritis. In our study, we analysed gastritis associated with oesophageal, cardiac and gastric adenocarcinomas according to the Sydney classification. Chronic gastritis was more common in gastric (88%) than in cardiac (56%) and oesophageal adenocarcinomas (38%). H. pylori was significantly more prevalent in gastric (73%) than in cardiac (34%) or oesophageal (21%) adenocarcinomas. Our results show that factors other than H. pylori must be involved in the histogenesis of cardiac adenocarcinomas. As the pattern of gastritis and the clinical features of cardiac adenocarcinomas are more comparable to oesophageal carcinomas than gastric carcinomas, we speculate that most of these tumours share similar aetiological factors with oesophageal carcinomas.

Adenocarcinoma↗
PubMed2003

On the existence and location of cardiac mucosa: an autopsy study in embryos, fetuses, and infants.

BACKGROUND: The incidence of gastric cardiac adenocarcinoma has increased in the last decades. Gaining insight into the pathogenesis of this lesion is hampered by the limited knowledge of the origin and histology of cardiac mucosa (CM). Currently, the location, extent, and even the existence of CM are controversial. AIMS: We studied the development of the gastro-oesophageal junction (GOJ) in embryos, fetuses, and infants to clarify if CM is a normal structure at birth and where it is located. SUBJECTS: Twenty one autopsy cases were evaluated ranging in age from 13 weeks' gestational age (GA) to seven months. METHODS: The distal oesophagus and proximal part of the stomach were embedded entirely. Serial sections were stained with haematoxylin-eosin and alcian blue/periodic acid-Schiff. The following parameters were measured: length of abdominal oesophagus; length of columnar lined oesophagus; length of CM; and distance from CM to angle of His. RESULTS: CM was present in all evaluated sections. Its mean length varied throughout gestation. A maximum value was reached at a GA of 16 weeks (1.2 mm). After term delivery it was very short (0.3-0.6 mm). CM was proximal to, or straddled, the angle of His in all cases. During gestation, the mucin staining pattern of the CM was to a high degree similar to that of the developing pyloric mucosa. CONCLUSIONS: CM develops during pregnancy and is present at birth as a normal structure. If the angle of His is taken as a landmark for the GOJ, CM is located in the distal oesophagus.

Aging↗
PubMed2002

Rectal washout with cytotoxic solution can be extended to the whole colon.

BACKGROUND: Rectal irrigation with a cytotoxic agent does not kill viable intraluminal cancer cells proximal to the primary tumour. To prevent implantation of these cells at the time of restorative proctectomy, the feasibility of retrograde whole-colon irrigation just before surgery was explored. METHODS: The cytotoxic efficacy of different combinations of povidone-iodine (PVPI) and Gastrografin was tested with the trypan blue exclusion test on a human colon carcinoma cell line (SW620) in vitro. Subsequently, a retrograde whole-colon lavage with PVPI 5 per cent and Gastrografin 12 per cent was performed in 14 euthyroid, non-allergic patients with colorectal cancer using a colostomy irrigation set. Thyroid function and mucosal damage were assessed. RESULTS: It took 2 min and approximately 1 litre of infused solution to reach the caecum in all patients. The solution was 100 per cent tumoricidal in vitro and remained so after colonic irrigation. Total serum tri-iodothyronine (T3) levels decreased and those of reverse T3 increased, but normalized after 1 week. Superficial epithelial desquamation was observed shortly after irrigation; however, complete restoration occurred within 7 days. CONCLUSION: A rectal washout can easily be extended to a retrograde irrigation of the whole colon in elective colorectal cancer surgery. This may help to prevent anastomotic and local recurrence due to implantation of viable exfoliated tumour cells.

Adult↗
PubMed2002

Microscopic colitis with giant cells.

AIMS: Collagenous colitis and lymphocytic colitis are the two types of microscopic colitis with specific morphological features. In this report we describe a new histopathological subtype of microscopic colitis. METHODS AND RESULTS: Colonoscopy in four patients with chronic watery diarrhoea showed no macroscopic abnormalities. The random biopsies from the colon showed subepithelial multinucleated giant cells in combination with the features of collagenous colitis in three patients and lymphocytic colitis in one patient. These multinucleated giant cells were positive for CD68. The density of macrophages was highest in the most superficial part of the lamina propria. In one patient, a previous biopsy showed features consistent with collagenous colitis without multinucleated giant cells. Treatment with budesonide led to the disappearance of diarrhoea in all four patients. CONCLUSIONS: The clinical and histopathological features of the four presented patients indicate that there exists a histopathological subtype of microscopic colitis characterized by the presence of subepithelial multinucleated giant cells, which probably arise from fusion of subepithelial macrophages. Analysis of more patients with this histopathological subtype of microscopic colitis is necessary to determine whether they also form a clinically distinct group.

Aged↗
PubMed2002

Positron emission tomography for assessment of the response to induction radiochemotherapy in locally advanced oesophageal cancer.

AIMS: This prospective study was designed to determine the utility of 18F-labelled deoxyglucose (FDG) in positron emission tomography (PET) (FDG-PET) for assessing the response to neoadjuvant chemoradiation therapy (CRT) in locally advanced oesophageal tumours. PATIENTS AND METHODS: Thirty-six patients with locally advanced oesophageal cancer (clinical T4 stage) without organ metastases, underwent FDG-PET before and 1 month after CRT. Patients were classified as major responders by serial FDG-PET when the post-CRT PET demonstrated a strong reduction of FDG uptake at the primary tumour site (>80% reduction of tumour-to-liver uptake ratio) without any abnormal FDG uptake elsewhere in the body. PET response was compared with histology obtained during post-induction transthoracic oesophagectomy. RESULTS: A strong correlation was found between the extent of lymph node (LN) involvement as shown by the pre-CRT PET and the major response rate (P = 0.001): such response occurred in nine of 11 N0M0 patients (82%), in three of nine N(1-2)M0 patients (33%) and in two of 16 patients (13%) with distant lymphatic spread. Such a correlation was not found for computed tomography or endoscopic ultrasonography. The sensitivity of serial FDG-PET for a major CRT response was 10 of 14 (71%), its specificity 18 of 22 (82%). The concordance between the response assessment by PET and histopathology was 78%. The median survival time after CRT of PET major responders compared with PET non-major responders was 16.3 months and 6.4 months, respectively. The metabolic response as measured by serial FDG-PET is a stronger prognostic factor for overall survival (P = 0.002) than the extent of LN involvement seen on the pretreatment FDG-PET (P = 0.087). CONCLUSIONS: These data indicate that CRT response as assessed by serial FDG-PET is strongly correlated with pathological response and survival.

Adenocarcinoma↗
PubMed2000

Utility of positron emission tomography for the staging of patients with potentially operable esophageal carcinoma.

PURPOSE: A prospective study of preoperative tumor-node-metastasis staging of patients with esophageal cancer (EC) was designed to compare the accuracy of 18-F-fluoro-deoxy-D-glucose (FDG) positron emission tomography (PET) with conventional noninvasive modalities. PATIENTS AND METHODS: Seventy-four patients with carcinomas of the esophagus (n = 43) or gastroesophageal junction (n = 31) were studied. All patients underwent attenuation-corrected FDG-PET imaging, a spiral computed tomography (CT) scan, and an endoscopic ultrasound (EUS). RESULTS: FDG-PET demonstrated increased activity in the primary tumor in 70 of 74 patients (sensitivity: 95%). False-negative PET images were found in four patients with T1 lesions. Thirty-four patients (46%) had stage IV disease. FDG-PET had a higher accuracy for diagnosing stage IV disease compared with the combination of CT and EUS (82% v 64%, respectively; P: =.004). FDG-PET had additional diagnostic value in 16 (22%) of 74 patients by upstaging 11 (15%) and downstaging five (7%) patients. Thirty-nine (53%) of the 74 patients underwent a 2- or 3-field lymphadenectomy in conjunction with primary curative esophagectomy. In these patients, tumoral involvement was found in 21 local and 35 regional or distant lymph nodes (LN). For local LN, the sensitivity of FDG-PET was lower than EUS (33% v 81%, respectively; P: =.027), but the specificity may have been higher (89% v 67%, respectively; P: = not significant [NS]). For the assessment of regional and distant LN involvement, compared with the combined use of CT and EUS, FDG-PET had a higher specificity (90% v 98%, respectively; P: =. 025) and a similar sensitivity (46% v 43%, respectively; P: = NS). CONCLUSION: PET significantly improves the detection of stage IV disease in EC compared with the conventional staging modalities. PET improves diagnostic specificity for LN staging.

Adenocarcinoma↗