Prognostic value of KIT/PDGFRA mutations in gastrointestinal stromal tumours (GIST): Polish Clinical GIST Registry experience.

BACKGROUND: Majority of gastrointestinal stromal tumours (GISTs) are characterised by KIT-immunopositivity and the presence of KIT/platelet-derived growth factor receptor alpha (PDGFRA) activating mutations. PATIENTS AND METHODS: Spectrum and frequency of KIT and PDGFRA mutations were investigated in 427 GISTs. Univariate and multivariate analysis of relapse-free survival (RFS) was conducted in relation to tumours' clinicopathologic features and genotype. RESULTS: Mutations were found in 351 (82.2%) cases, including 296 (69.3%) KIT and 55 (12.9%) PDGFRA isoforms. Univariate analysis revealed higher 5-year RFS rate in women (37.9%; P = 0.028) and in patients with gastric tumours (46.3%; P < 0.001). In addition a better 5-year RFS correlated with smaller tumour size ≤ 5 cm (62.7%; P < 0.001), tumours with mitotic index ≤ 5/50 high-power fields (60%; P < 0.001), and characterised by (very) low/moderate risk (70.2%; P = 0.006). Patients with GISTs bearing deletions encompassing KIT codons 557/558 had worse 5-year RFS rate (23.8%) than those with any other KIT exon 11 mutations (41.8%; P < 0.001) or deletions not involving codons 557/558 (33.3%; P = 0.007). Better 5-year RFS characterised patients with KIT exon 11 point mutations (50.7%) or duplications (40%). By multivariate analysis, tumours with PDGFRA mutations and KIT exon 11 point mutations/other than 557/558 deletions had lower risk of progression than with KIT exon 11 557/558 deletions (both Ps = 0.001). CONCLUSIONS: KIT/PDGFRA mutational status has prognostic significance for patients' outcome and may help in management of patients with GISTs.

Antibiotic treatment with ampicillin accelerates the healing of colonic damage impaired by aspirin and coxib in the experimental colitis. Importance of intestinal bacteria, colonic microcirculation and proinflammatory cytokines.

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for their anti-inflammatory, analgesic and antipyretic effects, however their use is associated with the broad spectrum of side effects observed in human as well as the experimental animals. Despite damaging activity of NSAIDs in upper gastrointestinal (GI) tract, these drugs exert deleterious influence in lower GI tract, including colon. The role of GI microflora in the pathogenesis of NSAIDs-induced experimental colonic damage is not completely understood. The aim of this study was 1) to evaluate the relative importance of the GI microflora on the experimental colonic damage in the presence of caused by NSAID, and 2) to assess the efficacy of antibiotic treatment with ampicillin on the process of healing of colitis. We compared the effect of vehicle, ASA applied 40 mg/kg intragastrically (i.g.) or the selective cyclooxygenase (COX)-2 inhibitor, celecoxib (25 mg/kg i.g.) without or with ampicillin treatment (800 mg/kg i.g.) administered throughout the period of 10 days, on the intensity of TNBS-induced colitis in rats. The severity of colonic damage, the alterations in the colonic blood flow (CBF) and myeloperoxidase (MPO) activity, the mucosal expression of TNF-α, IL-1ß, COX-2, VEGF and iNOS and the plasma concentration of TNF-α and IL-1ß were assessed. In all rats, the faeces samples as well as those from the colonic mucosa, blood, liver and spleen underwent microbiological evaluation for intestinal bacterial species including Escherichia coli and Enterococcus spp. The administration of TNBS resulted in macroscopic and microscopic lesions accompanied by the significant fall in the CBF, an increase in tissue weight and 4-5-fold rise in the MPO activity and a significant increase in the plasma IL-1ß and TNF-α levels. ASA or celecoxib significantly increased the area of colonic lesions, enhanced MPO activity and caused the marked increase in colonic tissue weight and plasma IL-1ß and TNF-α levels, as well as an overexpression of mRNA for IL-1ß and TNF-α, COX-2, VEGF and iNOS in the colonic tissue. ASA and coxib also resulted also in a significant increase of E. coli counts in the stool at day 3 and day 10 day of the observation compared with the intact rats. Moreover, E. coli translocation from the colon to the blood and extraintestinal organs such as liver and spleen in the group of rats treated without or with ASA and coxib. E. coli was the most common bacteria isolated from these organs. Treatment with ampicillin significantly attenuated the ASA- or celecoxib-induced increase in plasma levels of IL-1ß and TNF-α and suppressed the mucosal mRNA expression for IL-1ß and TNF-ß, COX-2, iNOS and VEGF in the colonic mucosa. Ampicillin administration caused a significant fall in the number of E. coli in the faeces at day 3 and day 10 of observation in ASA- and coxib-treated rats with colitis. Antibiotic therapy markedly reduced bacterial translocation to the colonic tissue and the extraintestinal organs such as the liver and spleen. We conclude that administration of ASA and to lesser extent of celecoxib, delays the healing of experimental colitis and enhances the alterations in colonic blood flow, proinflammatory markers such as IL-1ß, TNF-α, COX-2, iNOS and VEGF and increased intestinal mucosal permeability resulting in the intestinal bacterial translocation to the blood, spleen and liver. Antibiotic treatment with ampicillin is effective in the diminishing of the severity of colonic damage, counteracts both the NSAID-induced fall in colonic microcirculation and bacterial E.coli translocation to the extraintestinal organs.

Cyclooxygenase-2 (COX-2) is the key event in pathophysiology of Barrett's esophagus. Lesson from experimental animal model and human subjects.

Mixed reflux of the gastroduodenal contents induces the esophageal mucosal damage and inflammation progressing chronic esophagitis and premalignant Barrett's esophagus (BE). The role of cyclooxygenase-2 (COX-2) and chronic inflammation in the progression of BE toward adenocarcinoma of the esophagus has not been extensively studied in experimental models of BE in animals and in human subjects. We evaluated the expression of COX-2 in rat model of BE and examined the usefulness of COX-2 expression in determining the risk of malignant transformation in patients with BE treated with argon plasma coagulation (APC) that allows for effective ablation of metaplastic mucosa (group A) without or with proton pump inhibitors (PPI). In addition, the group B of patients was subjected to laparoscopic Nissen's fundoplication and group K that served as control, received PPI treatment only. Expression of COX-2 was evaluated in fresh-frozen biopsy specimens obtained from the distal esophagus in all 60 patients before and 12 months after treatment. In experimental studies, eighty rats were surgically prepared with esophagogastroduodenal anastomosis (EGDA) resulting in chronic esophagitis. At 4 months, the esophageal damage in EGDA rats was evaluated by macroscopic and histological index score, the plasma IL-1beta and TNF-alpha levels was determined by ELISA and the mucosal expression of COX-2 mRNA and COX-2 protein were assessed by RT-PCR and Western Blot, respectively. Chronic esophagitis was developed in all EGDA animals followed by the rise in the plasma TNF-alpha and IL-1beta levels. Histology revealed extensive esophageal ulcerations with development of columnar epithelium, formation of mucus glands in squamous epithelium, intestinal metaplasia distant to anastomosis consisting of goblet cells, infiltration of inflammatory cells including plasma cells and lymphocytes. COX-2 mRNA was absent in the esophageal mucosa of sham-control animals but strongly upregulated in metaplastic Barrett's epithelium. In BE patients, the overexpression of COX-2 was documented in patients with dysplasia. After APC (group A) or Nissen's fundoplication (group B), the expression of COX-2 mRNA was markedly reduced and these effects were positively correlated with histopathological findings. Controls failed to show significant alterations in COX-2 expression. We conclude that 1) EGDA rats serve as the suitable model of the chronic esophagitis by the gastrointestinal refluxate resembling many features of those observed in human Barrett's esophagus, as confirmed by severe morphology changes, excessive release of proinflammatory cytokines TNF-alpha and IL-1beta and overexpression of COX-2, and 2) the significant correlation of the degree of COX-2 overexpression with histopathological findings indicates the usefulness of this inducible biomarker as a valuable indicator of the risk of malignant transformation in patients with BE.

[Reduction of the radiation exposure of patients caused by selected interventional and angiographic procedures]. / Reduzierung der Strahlenexposition von Patienten bei ausgewählten interventionellen und angiographischen Massnahmen.

PURPOSE: To reduce patient doses caused by selected interventional and angiographic procedures using the digital C-arm unit "Multiskop". MATERIALS AND METHODS: After a patient study done previously, physical measurements with test phantoms were carried out, and physical-technical parameters such as distance between focus and image intensifier, additional filtration, and radiation dose per image were optimised. Then, the dose-area product (DAP) and the fluoroscopic time were measured for 130 percutaneous transluminal angioplasties (PTA), 40 PTA with stent implantation, 61 embolisations, and 302 digital subtraction angiographies (DSA). In the case of 16 PTA, 9 embolisations, and 38 DSA the number of radiographs was determined, and the DAP was divided into two parts, fluoroscopy and radiography. The measuring values were compared with data of the patient study done previously. RESULTS: The median values of the DAP and the fluoroscopic time amounted to 25 Gy cm2 and 9.7 min for PTA, 97 Gy cm2 and 8.5 min for PTA with stent implantation, 88 Gy cm2 and 17.2 min for embolisation as well as 54 Gy cm2 and 2.8 min for DSA. For the relation between DAP caused by fluoroscopy and radiography, and the number of radiographs, median values of 0.76 and 63 for PTA, 0.81 and 123 for embolisation as well as 1.85 and 134 for DSA were determined. In comparison to the patient study done previously the median values of the DAP were reduced by 31% for PTA, 26% for PTA with stent implantation, 55% for embolisation, and 38% for DSA. CONCLUSIONS: The comparison between the patient studies done previously and recently indicates the great potential of dose reduction for interventional and angiographic procedures. Although the X-ray equipment is ten years old the patient dose can be reduced by organizational and physical-technical modifications to such an extent that preliminary national reference dose values will not be exceeded. For further significant dose reductions while maintaining adequate image quality it will be necessary to purchase a modern X-ray equipment with pulsed fluoroscopy and automatic filter selection.

[Comparison of radiation exposure of patients caused by selected interventional and angiography procedures--initial results]. / Vergleich der Strahlenexposition von Patienten bei ausgewählten interventionellen und angiographischen Massnahmen--erste Ergebnisse.

PURPOSE: To determine and judge patient doses caused by selected interventional and angiographic procedures using the "Multiskip" digital C-arm unit. MATERIALS AND METHODS: The dose-area product and the fluoroscopic time were measured for 71 percutaneous transluminal angioplasties (PTA), 33 PTA with stent implantation, and 37 embolizations; in addition, they were also measured for 285 digital subtraction angiographies (DSA). In the case of 13 PTA, 10 embolizations, and 33 DSA the number of radiographs was determined, and the dose-area product was divided into two parts, fluoroscopy and radiography, applying a computer programme. RESULTS: The median values of the dose-area product and the fluoroscopic time amounted to 36 Gy cm2 and 11.5 min for PTA, 131 Gy cm2 and 14.4 min for PTA with stent implantation, 197 Gy cm2 and 24.5 min for embolisation as well as 87 Gy cm2 and 3.7 min for DSA. For the relation between dose-area products caused by fluoroscopy and radiography and the number of radiographs, median values of 0.67 and 70 for PTA, 0.58 and 153 for embolisation as well as 1.35 and 135 for DSA were determined. CONCLUSIONS: To reduce the relatively high patient doses the modification of the C-arm unit is aspired to realize pulsed fluoroscopy and automatic filter selection. Also experimental investigations will be done related to additional filtration and reduction of the image intensifier input dose rate and dose per frame, respectively. Then, the effect of dose reduction caused by these measures will be confirmed in a comparable patient study.

Preferential overexpression of CD44v5 in advanced gastric carcinoma Goseki grades I and III.

Tumor progression is associated with the clonal expansion of surviving cell variants. These results in cancer cell heterogeneity and selection of cells with a high malignant potential reflected also by the ability to metastasize. In seeding and implantation of cancer cells at the distant site cell adhesion molecules play a crucial role. Of particular interest is CD44 adhesion molecule, which possibly is involved in tumor metastasis development. Forty cases of an advanced gastric cancer were studied. Paraffin block were collected from the files. In addition to routine tumor typing, grading (Lauren and Goseki classifications) and staging, CD44 (standard, v5 and v6) was studied by immunohistochemistry and RT-PCR. CD44 immunoreactivity was found in 36 of the 40 studied cases. A significant overexpression of CD44v5 was noticed in gastric cancer. This was especially seen in Goseki's grades I and III (72.7% of cases) and was less common in Goseki's grades II and IV (44.4% of cases). CD44v6 was less commonly expressed. In some cases CD44 heterogeneity of neoplastic intravascular emboli was noticed and in some other cases stronger expression of CD44 was present in deeper parts of cancer infiltrate. Immunohistochemical expression was mostly in concert with CD44 gene expression as shown by RT-PCR results. Some discrepancies are discussed. These findings are interesting in view of better prognosis and different route of dissemination of Goseki's grades I + III compared with Goseki's grades II + IV of the gastric cancer. We have shown an overexpression of CD44v5 in an advanced gastric cancer, especially in Goseki's grades I and III. This could reflect a different malignant potential and a different route of dissemination of gastric well differentiated adenocarcinomas.

Adenocarcinoma developes in the "cirrhotic" not just atrophic gastric mucosa.

Helicobacter pylori has been postulated as a group 1 carcinogen, but the mechanism of gastric carcinogenesis remains to be elucidated. It is believed that gastric cancer morphogenesis follows Correa's paradigm of a gastritis-->atrophy-->metaplasia-->dysplasia-->cancer sequence. The aim of the present study was to investigate by histology non-cancerous gastric mucosa in early gastric cancer. Forty cases of early gastric cancer were collected from the files. In all cases of well differentiated adenocarcinoma mucosal atrophy and intestinal metaplasia were present in non-cancerous gastric mucosa. In addition, focal glandular hyperplasia was present in 83.3% of cases and hyperplastic surface epithelium was present in 50% of cases. Mucosal atrophy and intestinal metaplasia were seen in 90.5% of poorly differentiated adenocarcinomas. This was accompanied by surface epithelium hyperplasia in 66.7% and glandular hyperplasia in 47.6% of cases. In a diffuse early gastric cancer atrophy was present in 71.4%, intestinal metaplasia in 57.1%, while hyperplasia (either surface epithelium or glandular) was present in 42.8%. With the introduction of Genta's "strict definition" of gastric mucosal atrophy it became clear that atrophic gastric mucosa is not just a case of simple atrophy but can be in some respect compared to a cirrhotic organ.

Lauren's and Goseki's grade distribution does not change along with the progression from an early to advanced gastric carcinoma.

It is generally believed that tumor progression is associated with increased cancer cell heterogeneity, poorer differentiation and increased malignant potential. We tested this hypothesis by comparing a group of early and advanced gastric carcinomas. We retrieved from our files 40 cases of early gastric carcinoma and another 40 cases of advanced gastric carcinoma. Routine tumor typing, grading (Lauren and Goseki classifications) and staging was applied. We have shown that the proportion of histological grades in early and advanced gastric carcinoma does not change significantly. In addition, more poorly differentiated carcinomas were present both in early and advanced gastric carcinoma groups. This is in contrast with several other studies. This fact together with overexpression of CD44V5 isoform and fewer cancer cells circulating in the blood of patients suffering from this type of gastric carcinoma might influence the adjuvant therapy strategy. In summary, in the present study we noticed a similar distribution of Lauren's and Goseki's histological grades both in early and advanced gastric carcinoma.

Endoscopic and histological appearance of pancreatic metaplasia in the human gastric mucosa: a preliminary report on a recently recognized new type of gastric mucosal metaplasia.

Recently a new type of gastric mucosal metaplasia referred to as pancreatic metaplasia (pancreatic acinar metaplasia) has been recognized. The difference is characterized by the presence of epithelial cells with the cytoplasm strongly basophilic in the basal compartment, whereas in the middle and apical portions it is acidophilic and finely granular. In contrast to intramuscular heterotopic pancreas, foci of pancreatic metaplasia are located in the lamina propria of the gastric mucosa. They form lobules, small clusters, or may be single. The present series included 13 cases of pancreatic metaplasia found in gastroscopic specimens obtained from seven women and six men. We investigated the histological pattern and endoscopic changes. Based upon clinical data it was found that in five patients the gastric mucosa was defined as 'dichromatic'. It is possible that studies involving greater numbers of patients will permit closer correlation between the histological pattern of pancreatic metaplasia and the corresponding endoscopic changes.

Pregnancy associated diffuse malignant fibrous mesothelioma of peritoneum. Immunohistochemical studies of ectopic decidual reaction and concomitant myofibroblastic and mesothelial proliferations.

A case of diffuse proliferations in the peritoneum in a 24-year-old woman several months post partum has been reported. Multinodular growth of myofibroblastic cells without atypia was observed, which predominated and revealed a positive immunohistochemical reaction to muscle-specific actin and vimentin, and dispersed clusters of mesothelial cells showing a positive reaction to cytokeratin and vimentin, with moderate atypia and scarce mitotic figures. On cesarean section the greater omentum contained an ectopic decidua in the form of a nodule. Decidual cells, in part transforming into spindle-shaped cells, showed the presence of desmin. Multifocal proliferation of myofibroblasts, most probably of metaplastic type, concomitant with pregnancy-induced peritoneal deciduosis and diffuse progressive mesothelial proliferations has been identified.

Pancreatic metaplasia of the human gastric mucosa is associated with high expression of transforming growth factor alpha but not of epidermal growth factor.

Pancreatic acinar metaplasia of the gastric mucosa is a newly recognized entity. Its physiological relevance and association with other pathological conditions in the stomach remain to be elucidated. We studied by immunohistochemistry the expression of growth markers in the gastric mucosa in biopsies from 15 patients with recognized pancreatic metaplasia. Pancreatic metaplasia (both acinar and dispersed forms) was found in routine paraffin sections and confirmed by strong lipase immunoreactivity. In parallel paraffin sections we performed immunostaining for epidermal growth factor (EGF), transforming growth factor-alpha (TGF alpha) and epidermal growth factor receptor (EGFr) using a biotin streptavidin method. Strong expression of TGF alpha but only weak expression of EGF was noted within metaplastic mucosa. EGFr was strongly expressed, not only in areas of pancreatic metaplasia but also in the surrounding gastric mucosa.

Dispersed and acinar forms of pancreatic metaplasia in human gastric mucosa.

Pancreatic acinar cell metaplasia of the gastric mucosa is a newly recognized entity. Its physiological relevance and association with other gastric pathological conditions remains to be elucidated. We studied morphology of pancreatic metaplasia of the gastric mucosa in 15 cases. Two morphological forms of pancreatic metaplasia were noticed: an acinar form and a diffuse form. The diffuse form is characterized by small foci of pancreatic metaplasia dispersed in the gastric mucosa without any separation from the surrounding gastric glands. The acinar form is characterized by acini of pancreatic metaplasia separated from the surrounding gastric mucosa by strands of connective tissue and single smooth muscle cells. Acinar form of pancreatic metaplasia seems to be spared by the chronic atrophic gastritis involving the neighboring gastric mucosa.

Cytological pattern of multihormonal carcinoid of the appendix with metastasis to the liver corresponding a clinical insulinoma.

The paper describes a cytological pattern of carcinoid of the appendix metastasizing to the liver and lymph nodes, clinically manifested by increased insulin level, in whose cells immunohistochemical studies revealed also the presence of gastrin and somatostatin. The case was confirmed by autopsy examination.

Selected immunohistochemical markers in stromal neoplasms of the gastrointestinal tract.

We studied immunohistochemical reactions to vimentin, desmin and protein S-100 in 43 cases of stromal tumors of the gastrointestinal tract. The material studied included: 1 esophageal tumor, 18 gastric tumors, 19 small intestinal tumors and 5 colonic tumors, classified in 13 cases as benign and in 30 cases as malignant neoplasms of various degree of malignancy. Mean age of the patients was 58.9 years. A positive reaction to vimentin was found in 37 cases, a negative reaction concerned an esophageal tumor, two benign tumors (gastric and small intestinal) and three malignant tumors (gastric and two small intestinal). A positive reaction to desmin was detected in an esophageal tumor and in nine gastric tumors. Only one benign small intestinal tumor and three benign colonic tumors showed a positive reaction to desmin. Protein S-100 was found in an esophageal tumor and in 7 out of 18 gastric tumors and in 12 out of 24 intestinal tumors. Coexpression of vimentin and desmin was found in 8 gastric tumors, only in one small intestinal tumor and in three colonic tumors. Three gastric tumors showing both these reactions were all benign. Coexpression of desmin and protein S-100 was found in 7 out of 43 tumors of the alimentary tract. In six cases these tumors were benign. Basing on the results we may say that the presence of these antigens reflects the degree of differentiation of gastrointestinal stromal tumors of the gastrointestinal tract, though it does not allow to choose unequivocally conclusions as to their histogenesis.

Gastric antral vascular ectasia. A case report.

A case of vascular lesion of angiodysplastic type in the pyloric part of the stomach has been reported in a patient with chronic viral hepatitis. The diagnosis was made from clinical symptoms, endoscopic and histopathologic findings in the specimens obtained during gastroscopy. Many authors emphasize a correlation between the incidence of "gastric antral vascular ectasia" and liver diseases, especially cirrhosis with portal hypertension. A review of bibliography with particular consideration of its etiology has been presented.

[Alveolar soft part sarcoma--case report]. / Alveolar soft part sarcoma--opis przypadku.

A case of alveolar soft part sarcoma has been described in a 12-year from old girl. Immunohistochemical reactions on paraffin sections from the tumour were directed towards the presence of desmin , vimentin and neurospecific enolase. Positive reaction to desmin and neurospecific enolase was found in neoplastic cells.

[Immunoreactivity directed towards human papillomavirus (HPV) structural antigen in perianal epithelial proliferation in humans]. / Immunoreaktywnosc w kierunku antygenu strukturalnego wirusa Papilloma (HPV) w perianalnych proliferacjach nablonkowych u ludzi.

Immunoreactivity directed towards the presence of a structural antigen of Papilloma virus (HPV) was studied in patients with benign epithelial proliferations in the perianal area, squamous cell and cloacogenic carcinomas of the rectum and anus, using Dako serum kits. Positive reaction was found in five of eleven pointed condylomas and in one squamous cell papilloma, which is in accordance with other reports. Negative reaction in patients with squamous cell carcinomas may result from methodologic limitations of immunohistochemical studies. In patients with cloacogenic carcinomas it may also indicate a lack of relationship between this type of a neoplasm and HPV infection. The latter probably requires the presence of mature keratocytes to proliferate.

Coexpression of vimentin and desmin in gastric leiomyomas. An immunohistochemical study in paraffin sections.

The aim of the study was to evaluate the incidence of the reactions for vimentin and desmin in gastric leiomyomas routinely processed in formalin and embedded i paraffin. The material studied included four benign leiomyomas, seven malignant leiomyomas and three malignant epithelioid leiomyomas. A positive reaction to vimentin was found in 13 out 14 leiomyomas under study. The number of neoplastic cells showing vimentin expression was larger in malignant, especially epithelioid leiomyomas than in non-malignant leiomyomas. A positive reaction for desmin in neoplastic cells was found in 9 leiomyomas 64%. One non-malignant leiomyoma showed a moderate reaction. In the remaining eight cases the reaction was weak and occurred in single neoplastic cells. Coexpression of vimentin and desmin in neoplastic cells occurred in 8 out of 9 leiomyomas with a positive reaction for desmin. Coexpression of vimentin and desmin occurred also in the smooth muscle cells of blood vessels in all 14 cases. A weak reaction for desmin or its lack in the tumour cells of leiomyomas with its marked expression in the smooth muscle cells of the blood vessels and gastric wall outside the tumor points rather to a small number of desmin filaments in the neoplastic cells than to their destruction by fixation in formalin. The occurrence of the reaction to desmin only in a limited number of neoplastic cells questions the reliability of its use in the oligopiopsy material.