Vaccine-induced SARS-CoV-2 antibody response: the comparability of S1-specific binding assays depends on epitope and isotype discrimination.

Background: Quantification of the SARS-CoV-2-specific immune response by serological immunoassays is critical for the management of the COVID-19 pandemic. In particular, neutralizing antibody titers to the viral spike (S) protein have been proposed as a correlate of protection (CoP). The WHO established the First International Standard (WHO IS) for anti-SARS-CoV-2 immunoglobulin (Ig) (NIBSC 20/136) to harmonize binding assays with the same antigen specificity by assigning the same unitage in binding antibody units (BAU)/ml. Method: In this study, we analyzed the S1-specific antibody response in a cohort of healthcare workers in Germany (n = 76) during a three-dose vaccination course over 8.5 months. Subjects received either heterologous or homologous prime-boost vaccination with ChAdOx1 nCoV-19 (AstraZeneca) and BNT162b2 (Pfizer-BioNTech) or three doses of BNT162b2. Antibodies were quantified using three anti-S1 binding assays (ELISA, ECLIA, and PETIA) harmonized to the WHO IS. Serum levels of neutralizing antibodies were determined using a surrogate virus neutralization test (sVNT). Binding assays were compared using Spearman's rank correlation and Passing-Bablok regression. Findings: All assays showed good correlation and similar antibody kinetics correlating with neutralizing potential. However, the assays show large proportional differences in BAU/ml. ECLIA and PETIA, which detect total antibodies against the receptor- binding domain (RBD) within the S1 subunit, interact similarly with the convalescent plasma-derived WHO IS but differently with vaccine serum, indicating a high sensitivity to the IgG/IgM/IgA ratio. Conclusion: All three binding assays allow monitoring of the antibody response in COVID-19-vaccinated individuals. However, the assay-specific differences hinder the definition of a common protective threshold in BAU/ml. Our results highlight the need for the thoughtful use of conversion factors and consideration of method-specific differences. To improve the management of future pandemics and harmonize total antibody assays, we should strive for reference material with a well-characterized Ig isotype composition.

Genomic Complexity as a Biomarker to De-Escalate Adjuvant Imatinib Treatment in High-Risk Gastrointestinal Stromal Tumor.

PURPOSE: Adjuvant imatinib treatment is recommended for patients with localized gastrointestinal stromal tumor (GIST) at high risk of recurrence. Almost half of high-risk patients are cured by surgery alone, indicating a need for improved selection of patients for adjuvant therapy. The aim of this study was to investigate if genomic tumor complexity could be used as a prognostic biomarker. METHODS: The discovery cohort consisted of patients who underwent resection of primary GIST at Oslo University Hospital between 1998 and 2020. Karyotypes were categorized as simple if they had ≤ 5 chromosomal changes and complex if there were > 5 chromosomal aberrations. Validation was performed in an independent patient cohort where chromosomal imbalances were mapped using comparative genomic hybridization. RESULTS: Chromosomal aberrations were detected in 206 tumors, of which 76 had a complex karyotype. The most frequently observed changes were losses at 14q, 22q, 1p, and 15q. The 5-year recurrence-free survival (RFS) in patients classified as very low, low, or intermediate risk was 99%. High-risk patients with a simple tumor karyotype had an estimated 5-year RFS of 94%, and patients with a complex karyotype had an estimated 5-year RFS of 51%. A complex karyotype was associated with poor RFS in patients with and without adjuvant imatinib treatment and in multivariable analysis adjusted for tumor site, size, mitotic count, and rupture. The prognostic impact of genomic complexity was confirmed in the validation cohort. In both cohorts, the 5-year disease-specific survival was > 90% for high-risk patients with genomically simple tumors. CONCLUSION: Genomic tumor complexity is an independent prognostic biomarker in localized, high-risk GIST. Recurrences were infrequent for tumors with simple karyotypes. De-escalation of adjuvant imatinib treatment should be explored in patients with cytogenetically simple GISTs.

The utilization of multidisciplinary tumor boards (MDT) in clinical routine: results of a health care research study focusing on patients with metastasized colorectal cancer.

PURPOSE: Multidisciplinary tumor boards (MDT) have been advocated as standard of care in modern oncology. German guidelines for metastasized colorectal cancer (mCRC) recommend MDT discussion of colon cancer patients after completion of primary tumor therapy but stage IV colon cancer as well as rectal cancer patients prior to any therapy. In this health care research study, we evaluated application and decisional consequences of this approach in clinical routine. METHODS: All major institutions providing oncological care in southern Lower Saxony and Northern Hesse (N = 11) were invited. Patients with mCRC diagnosed between 01/2011 and 12/2013 were eligible. Data were collected using a standardized patient report form and stored in a GCP-conform EDC-system (secuTrial®). RESULTS: A university medical center, four teaching hospitals, one communal hospital, and three oncological focus practices participated in the study. In total, 470 patients with a median age of 70 years were enrolled. Guideline conform MDT discussion was performed in 63% of operated colon cancer patients, 38% of stage IV colon cancer patients and 47% of rectal cancer patients, respectively. Resection of metastases was performed in 41% of cases. Patients ≥70 years (n = 250) received significantly more often treatment following MDT discussion (86 versus 64%, p = 0.0002). Not the resection rate (48 versus 57%, p = 0.1574) but indication for preoperative chemotherapy (57 versus 33%, p = 0.0056) significantly differed when patients with single organ metastases experienced MDT discussion. CONCLUSIONS: MDT discussion is not as established as advocated by national guidelines. Treatment decisions differ especially in older patients and those with single organ metastases.

Testing for apolipoprotein(a) phenotype using isoelectric focusing and immunoblotting technique.

Increased levels of lipoprotein(a) are known as an independent risk factor for atherosclerosis, heart disease, and stroke in man. Even in children it could show that elevated levels of Lp(a) are an independent thromboembolic risk factor. Levels of Lp(a) are influenced by several factors like nutrition, kidney or liver function, or acute-phase reaction. But the most important factors are genetically determined. About 45% of genetic variation depends on polymorphisms and mutations in the promotor region. About 50% are dependent on the size polymorphism of Lp(a). The number of Kringle 4 domains varies between 12 and over 40. The number of Kringle 4 repeats correlates negatively with the level of Lp(a) in plasma. The determination of apo(a) phenotype is able to estimate thromboembolic risk due to this risk factor.

Ultrasonic scalpel causes greater depth of soft tissue necrosis compared to monopolar electrocautery at standard power level settings in a pig model.

BACKGROUND: Ultrasonic scalpel (UC) and monopolar electrocautery (ME) are common tools for soft tissue dissection. However, morphological data on the related tissue alteration are discordant. We developed an automatic device for standardized sample excision and compared quality and depth of morphological changes caused by UC and ME in a pig model. METHODS: 100 tissue samples (5 × 3 cm) of the abdominal wall were excised in 16 pigs. Excisions were randomly performed manually or by using the self-constructed automatic device at standard power levels (60 W cutting in ME, level 5 in UC) for abdominal surgery. Quality of tissue alteration and depth of coagulation necrosis were examined histopathologically. Device (UC vs. ME) and mode (manually vs. automatic) effects were studied by two-way analysis of variance at a significance level of 5%. RESULTS: At the investigated power level settings UC and ME induced qualitatively similar coagulation necroses. Mean depth of necrosis was 450.4 ± 457.8 µm for manual UC and 553.5 ± 326.9 µm for automatic UC versus 149.0 ± 74.3 µm for manual ME and 257.6 ± 119.4 µm for automatic ME. Coagulation necrosis was significantly deeper (p < 0.01) when UC was used compared to ME. The mode of excision (manual versus automatic) did not influence the depth of necrosis (p = 0.85). There was no significant interaction between dissection tool and mode of excision (p = 0.93). CONCLUSIONS: Thermal injury caused by UC and ME results in qualitatively similar coagulation necrosis. The depth of necrosis is significantly greater in UC compared to ME at investigated standard power levels.

Testing for lipoprotein(a) concentration and apolipoprotein(a) phenotypes: method standardization and pediatric reference values.

Increased levels of lipoprotein(a) (Lp[a])are known independent risk factor for atherosclerosis, heart disease, and stroke in adults. Even in children it could be shown that elevated levels of Lp(a) are an independent risk factor for symptomatic thromboembolism. The aim of this work was to describe the methods used for evaluating Lp(a) phenotypes, to link them to Lp(a) plasma concentrations, and to establish age-dependent reference values in children. Lp(a) plasma concentrations were measured with enzyme-linked immunosorbent assay technique in parallel to agarose gel electrophoresis and subsequent anti-apolipoprotein(a) immunoblotting. We included 184 pediatric patients with stroke or venous thromboembolism, and 150 healthy age-matched controls in this study. In the control children we could find a mean Lp(a) concentration of 3 mg/dL for children 1 to 12 months of age, and in subjects 1.2 to 18 years of age, the mean Lp(a) concentration was 10 mg/dL. Using percentile classification the upper percentile cut-offs were as follows: age 3 to 6 months: 14 mg/dL; 6.1 to 12 months: 15 mg/dL; 1.1 to 9 years: 22 mg/dL; and 9.1 to 18 years: 30 mg/dL, respectively. In the present study we have established age-dependent reference values of plasma Lp(a) concentrations. The latter will help to harmonize international pediatric studies and to further evaluate the role of elevated Lp(a) in childhood vascular disease.

Expression of p16INK4A in gastrointestinal stromal tumours (GISTs): two different forms exist that independently correlate with poor prognosis.

AIMS: To determine the prognostic impact of p16INK4A expression in gastrointestinal stromal tumours (GISTs), which is currently being questioned, with both loss and overexpression said to be correlated with poor prognosis. METHODS AND RESULTS: Two different forms of p16INK4A were identified, presenting with predominantly nuclear and cytoplasmic expression pattern, respectively. The immunohistochemical expression of the two forms and their correlation with E2F1 and prognosis were analysed in a series of 120 GISTs with clinical follow-up. Low nuclear p16INK4A expression correlated with E2F1 up-regulation, higher mitotic counts, and tumour progression. The prognostic value of nuclear p16INK4A expression was only marginally significant (P=0.05). Strong expression of the cytoplasmic p16INK4A form was significantly associated with shorter disease-free survival (P=2x10(-5)). The prognostic impact of strong expression of the cytoplasmic p16INK4A form was independent of anatomical localization, tumour size and mitotic counts, and significant even among the cohort of tumours with high malignant potential. CONCLUSIONS: Low expression of the nuclear p16INK4A form and strong expression of the cytoplasmic p16INK4A form both represent two independent parameters each associated with tumour progression in GISTs. Low nuclear p16INK4A expression enables E2F1 up-regulation and consecutive accelerated cell proliferation. In contrast, strong cytoplasmic p16INK4A expression probably reflects a negative feedback loop as a result of (as yet unknown) oncogenic events.

Localization- and mutation-dependent microRNA (miRNA) expression signatures in gastrointestinal stromal tumours (GISTs), with a cluster of co-expressed miRNAs located at 14q32.31.

The molecular biology and clinical behaviour of gastrointestinal stromal tumours (GISTs) are associated with their anatomical localization (stomach or intestine), and also with the mutation status of the receptor tyrosine kinases KIT and PDGFRA. Twelve GISTs were evaluated for differential miRNA expression signatures by use of microarrays representing 734 human miRNAs. Thirty-two miRNAs were found to be differentially expressed according to localization and mutation status. Differential expression was further analysed and confirmed for four miRNAs (miR-132, miR-221, miR-222, and miR-504) by qRT-PCR in 49 additional GISTs. Differentially expressed miRNAs were functionally mapped to KIT/PDGFRA signalling and G1/S-phase transition of the cell cycle, revealing 22 predicted miRNA/mRNA interactions for ten gene targets from KIT/PDGFRA signalling, and 12 interactions for 12 gene targets of G1/S-phase transition. Moreover, the expression of 44 miRNAs clustered in a genetically imprinted region at 14q32.31 was found to be strongly correlated in the microarray analysis. This was confirmed for two selected miRNAs (miR-134 and miR-370) from the 14q32.31 cluster by qRT-PCR in 49 additional GISTs, and the expression of these two miRNAs was significantly lower in GISTs with 14q loss, and also in GISTs with tumour progress. miRNA profiling may prove to be a key determinant of the biology and clinical features of GISTs.

Role of endogenous testosterone concentration in pediatric stroke.

Previous studies have indicated a male predominance in pediatric stroke. To elucidate this gender disparity, total testosterone concentration was measured in children with arterial ischemic stroke (AIS; n = 72), children with cerebral sinovenous thrombosis (CSVT; n = 52), and 109 healthy controls. Testosterone levels above the 90th percentile for age and gender were documented in 10 children with AIS (13.9%) and 10 with CSVT (19.2%), totaling 16.7% of patients with cerebral thromboembolism overall, as compared with only 2 of 109 controls (1.8%; p = 0.002). In multivariate analysis with adjustment for total cholesterol level, hematocrit, and pubertal status, elevated testosterone was independently associated with increased disease risk (odds ratio [95% confidence interval]: overall = 3.98 [1.38-11.45]; AIS = 3.88 [1.13-13.35]; CSVT = 5.50 [1.65-18.32]). Further adjusted analyses revealed that, for each 1nmol/l increase in testosterone in boys, the odds of cerebral thromboembolism were increased 1.3-fold.

Preoperative chemoradiotherapy in locally advanced rectal cancer: correlation of a gene expression-based response signature with recurrence.

Preoperative chemoradiotherapy is recommended for locally advanced rectal cancer (UICC stage II/III). We recently demonstrated that responsive and nonresponsive tumors showed differential expression levels of 54 genes. In this follow-up study, we investigated the relationship between this gene set and disease-free (DFS) and overall survival (OS). Pretherapeutic biopsies from 30 participants in the CAO/ARO/AIO-94 trial of the German Rectal Cancer Study Group were analyzed using gene expression microarrays. Statistical analysis was performed to identify differentially expressed genes between recurrent and nonrecurrent tumors and to correlate these changes with disease recurrence and outcome. After a median follow-up of 59 months, seven of eight patients with recurrent disease was a nonresponder, and one responsive tumor recurred. Response to chemoradiotherapy was significantly correlated with an improved DFS (log rank P=0.028), whereas OS did not differ significantly (P=0.11). Applying a class comparison analysis, we identified 20 genes that were differentially expressed between recurrent and nonrecurrent tumors (P<0.001). Analyzing the first two principal components of the 54 genes previously identified to predict response, we observed that this response signature correlated with an increased risk of cancer recurrence. These data suggest that the genetic basis of local response also affects the genetic basis of tumor recurrence. Genes that are indicative of nonresponse to preoperative chemoradiotherapy might also be linked to an increased risk of tumor recurrence.

Does imatinib turn recurrent and/or metastasized gastrointestinal stromal tumors into a chronic disease? - single center experience.

BACKGROUND: Gastrointestinal stromal tumors (GIST) are mesenchymal tumors of the gastrointestinal tract supposed to arise from the cells of Cajal because of gain-of-function mutations of the tyrosine receptor kinases c-kit or platelet-derived growth factor receptor A. Imatinib selectively inhibits the kinase activity of both receptors. Despite this breakthrough in the treatment of GIST, resistance against imatinib has been reported to be as high as 50% after the first 2 years of treatment. AIM: Outcome of 13 consecutive patients with relapsed or metastasized GIST who were treated with imatinib was analyzed. RESULTS: Mean duration of treatment was 53.5 months. Four patients developed progressive disease and died after a mean treatment time of 31 months in spite of increase of imatinib dosages to 800 mg daily. Two patients (23%) developed a progressive disease after 46 months or 52 months of treatment. Two patients had a stable disease and five had a partial response. The overall progression rate was 46%, the mean survival time since primary diagnosis was 85.8 months. CONCLUSION: From our experience, frequency of resistance development to imatinib may be below that given in the literature (50% after 2 years). Individual treatment in specialized centers may improve compliance.

Bites and stings by exotic pets in Europe: an 11 year analysis of 404 cases from Northeastern Germany and Southeastern France.

INTRODUCTION: The presence of exotic, and sometimes venomous, pets in European homes is becoming more common. This phenomenon is the basis of a French-German cooperative evaluation of the species causing the injuries and the circumstances, severity, and treatment of the envenomations METHODS: A retrospective, descriptive, cross-sectional, case series of data from 1996 to 2006. The study sample consists of all cases of bites and stings by exotic pets that were registered at four poisons European poisons centers. The inclusion criteria were bites and stings of human beings. RESULTS: From 1996 to 2006 four poisons centers in Europe were consulted on 404 bites and stings by exotic pets. The average age of the patients was 36 (2 to 75) years and 73% of the patients were male. The severity of the envenomations, according to the Poisoning Severity Score, was as follows: 29 severe (7.1%), 55 moderate (14.2%) and 320 minor (78.7%). There were no fatalities in this case series. Exotic snakebites from rattlesnakes, cobras, mambas, and other venomous snakes caused 39% of envenomations, aquatic animals (mostly lionfish of the Pterois genus and stingrays) caused 30% of envenomations and arthropods (tarantulas and scorpions) caused 27% of envenomations. All severe envenomations were caused by venomous snakes. CONCLUSIONS: European healthcare professionals may encounter patients bitten or stung by exotic pets. Poisons center consultation can help manage these unusual presentations and help obtain rarely used antivenoms.

Genetics of hemostasis: differential effects of heritability and household components influencing lipid concentrations and clotting factor levels in 282 pediatric stroke families.

BACKGROUND: The identification of heritable and environmental factors possibly influencing a condition at risk should be a prerequisite for the search for the proportion of variance attributable for shared environmental effects (c(2)) modulating the risk of disease. Such epidemiologic approaches in families with a first acute ischemic stroke during early childhood are lacking. OBJECTIVES: Our goal was to estimate the phenotypic variation within lipid concentrations and coagulation factor levels and to estimate the proportions attributable to heritability (h(2)r) and c(2) in pediatric stroke families. METHODS: Blood samples were collected from 1,002 individuals from 282 white stroke pedigrees. We estimated h(2)r and c(2) for lipoprotein (a) [Lp(a)], cholesterol, high-density lipoprotein, low-density lipoprotein (LDL), fibrinogen, factor (F) II, FV, FVIIIC, von Willebrand factor (vWF), antithrombin, protein C, protein S, plasminogen, protein Z, total tissue factor pathway inhibitor (TFPI), prothrombin fragment F1.2, and D-dimer, using the variance component method in sequential oligogenetic linkage analysis routines. RESULTS: When incorporating h(2)r and c(2) in one model adjusted for age, blood group, sex, smoking, and hormonal contraceptives, significant h(2)r estimates were found for Lp(a), LDL, fibrinogen, protein C, and protein Z. In addition to the significant h(2)r estimates, c(2) showed a significant effect on phenotypic variation for fibrinogen, protein C, and protein Z. A significant c(2) effect was found for cholesterol, and plasma levels of FII, FV, vWF, antithrombin, protein S, plasminogen, and TFPI, ranging from 9.3% to 33.2%. CONCLUSIONS: Our research stresses the importance of research on the genetic variability and lifestyle modifications of risk factors associated with pediatric stroke.

Fibrillin-1 in incisional hernias: an immunohistochemical study in scar and non-scar regions of human skin and muscle fasciae.

Incisional hernias represent one of the most common complications after laparotomy. Specific pre-operative risk factors have not yet been identified. Recent studies indicate that changes in extracellular matrix components such as collagen I and collagen III may be involved in hernia development. In the present study we have evaluated the significance of fibrillin-1 in hernia development as one of the main components of the extracellular matrix. Tissue samples from non-scar skin and muscle fascia of 12 patients with incisional hernias as well as from the respective scar tissues were obtained. Corresponding tissue samples of 10 patients with normal postoperative wound healing served as controls. Distribution of fibrillin-1 was evaluated immunohistochemically. Differences in fibrillin-1 distribution in the non-scar tissues of muscle fascia have been found in patients with incisional hernia, compared to those without hernia. In scar regions of both patient groups, slight differences in the pattern of fibrillin-1 were observed. A tendency to a differential deposition of fibrillin-1 in skin samples, although hardly quantifiable, was observed as well. Our results suggest that fibrillin-1 is a relevant factor contributing to tissue stability. Disturbances in its deposition, even before scar formation, may be an important factor to the development of incisional hernias.

Immune cells in primary gastrointestinal stromal tumors.

INTRODUCTION: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. They are regarded as having relatively uniform histology, although their potential for malignant behavior varies. Despite a strong promoting role of tumor-infiltrating innate immune cells in neoplastic progression, the presence of immune cells in GISTs has not yet been studied. METHODS: A total of 47 untreated, c-kit-positive primary GISTs were immunohistochemically analyzed to distinguish histiocytic and dendritic cells (DCs) (KIM-1P, fascin, and CD68) from cells of lymphoplasmacellular origin (CD3, CD20, and CD56). Furthermore, the gene expression of proinflammatory cytokines was characterized by real-time, reverse transcription-PCR analysis of total RNA extracted from frozen tissue samples. RESULTS: KIM-1P+ cells were the dominant immune cells (851+/-295 cells/mm2) and were scattered among the tumor cells. Most of the KIM-1P+ cells showed cellular projections characteristic of DCs. Fascin positivity identified a subgroup of DCs. In comparison to KIM-1P+ cells, there were significantly fewer CD68+ macrophages (196+/-217 cells/mm2). CD3+ T cells were the dominant lymphocytes (201+/-331 cells/mm2), whereas B cells (60+/-126 cells/mm2) were few. On transcriptional level, a concomitant gene expression of cytokines for the classical acute phase cytokines TNF-alpha and IL-6 was missing, thus supporting the rather innate status of immune cells. CONCLUSION: GISTs contain, beside T lymphocytes, a high number of monocyte-derived cells, which we suggest are, at least in part, immature DCs. Together with the lack of gene expression of inflammatory cytokines in tumor tissue our results point to a possible 'symbiotic relationship' between the tumor and the local immune cells.

C-reactive protein and fibrinogen in acute stroke patients with and without sleep apnea.

BACKGROUND AND PURPOSE: Although sleep apnea (SA) is a risk factor for ischemic stroke and an important prognosticator in affected patients, the exact pathophysiological link between SA and stroke remains to be established. We investigated whether levels of C-reactive protein (CRP) and fibrinogen are increased in patients with acute stroke and SA compared with stroke patients without SA. PATIENTS AND METHODS: 117 consecutive patients with ischemic stroke admitted to our stroke unit within 12 h after stroke onset were included in this study. On admission, CRP and fibrinogen levels were determined. All patients received cardiorespiratory polygraphy during the first 72 h of their hospital stay. In all patients, demographic data, National Institutes of Health Stroke Scale score and cerebrovascular risk factors were assessed. RESULTS: SA defined by an apnea-hypopnea index (AHI) of > or =10/h was found in 64 (55%) patients. Elevated CRP and fibrinogen levels were seen twice as often in patients with SA than in patients without (CRP: 52 vs. 26%; fibrinogen: 72 vs. 37%). After multivariate logistic regression analysis, an AHI of > or =10/h was independently correlated with raised levels of both of these parameters. CONCLUSION: SA is independently associated with raised levels of CRP and fibrinogen in patients with acute ischemic stroke. We assume that both proteins are part of the pathophysiological pathway linking SA to stroke.

Site-dependent differential KIT and PDGFRA expression in gastric and intestinal gastrointestinal stromal tumors.

In gastrointestinal stromal tumors (GISTs), mutually exclusive gain-of-function mutations of KIT and PDGFRA are associated with different mutation-dependent clinical behavior. Taking into account the well-known different clinical behavior of GISTs from the stomach or the intestine, the aim of the current study is to evaluate the mutation- and site-dependent effects on mRNA and protein expression of KIT and PDGFRA in a large series of primary GISTs. Fresh-frozen tissue of 53 primary GISTs from gastric (75%) or intestinal (25%) sites were analyzed for mutation of KIT or PDGFRA using direct sequencing. Furthermore, KIT and PDGFRA mRNA and protein expression were determined using quantitative RT-PCR and quantitative densitometric evaluation of Western blot data. Each tumor either had a mutation of KIT (79%) or PDGFRA (21%). All GISTs with PDGFRA mutation were from gastric sites. Mutation-dependently, GISTs with KIT mutation had a significantly higher expression of KIT and at the same time a significantly lower expression of PDGFRA compared to GISTs with PDGFRA mutation. Site-dependently, gastric GISTs had a significantly higher expression of PDGFRA and a significantly lower expression of KIT compared to intestinal GISTs. Additionally, even if the KIT-mutated GISTs alone were considered, a significantly higher expression of PDGFRA could be observed in gastric than in intestinal tumors. We also found a significant correlation between a higher protein expression of PDGFRA and longer disease-free survival. The correlation of gastric site and PDGFRA mutation with higher PDGFRA expression and longer disease-free survival suggests different regulatory roles of KIT and PDGFRA gene expression on the control of cell proliferation, and, thereby on clinical behavior. The higher PDGFRA expression in gastric GISTs possibly contributes to the well-known site-dependent clinical behavior.

Multicentric sporadic gastrointestinal stromal tumors (GISTs) of the stomach with distinct clonal origin: differential diagnosis to familial and syndromal GIST variants and peritoneal metastasis.

Most sporadic gastrointestinal stromal tumors (GISTs) occur solitary, whereas a multicentric appearance is suspicious for a familial or syndromal setting such as with germline mutations of proto-oncogene tyrosine protein kinase Kit (KIT) or platelet derived growth factor receptor alpha (PDGFRA), or even for metastases. The aim of this study was to evaluate whether multicentric sporadic GISTs are of clonal origin. Four patients with 1 clinically apparent tumor (mean size 5.6 cm) and 1 to 3 further small incidental tumors (mean size 0.7 cm) were analysed by mutation analysis and comparative genomic hybridization for mutations of KIT and PDGFRA and chromosomal imbalances in their tumors. No clinicopathologic features have been found being indicative of one of the established familial or syndromal GIST variants. Each of the small GISTs were localized in the muscularis propria, and were visible from the serosal but not from the mucosal side. Different mutations of KIT and PDGFRA were present among individual tumors of each patient, and germline mutation of KIT and PDGFRA could be excluded. Comparative genomic hybridization revealed a mean count of 7 chromosomal imbalances in the clinically apparent tumors compared with a mean count of 0.3 in the small incidental counterparts. Sporadic GISTs can appear multicentric by coincidence. They are an important differential diagnosis to familial and syndromal GIST variants, or even to peritoneal metastases. Different mutations of KIT and PDGFRA among individual tumors in 1 patient refer to different clonal origin of multicentric sporadic GISTs. The type of mutation of KIT and PDGFRA was independent of tumor size, whereas small GISTs <1 cm rarely had genomic imbalances.

Surgical treatment in cocaine body packers and body pushers.

OBJECTIVE: Body packers smuggle cocaine by swallowing containers filled with the drugs, whilst body pushers conceal the containers in the rectum or vagina. In a collaborative effort between the Department of General Surgery, two major airports and Poisons Centre, we performed a retrospective study to develop an algorithm for the treatment of ruptured cocaine-filled containers. MATERIALS AND METHODS: The data of all cocaine body packers and body pushers who were identified at the airports of Frankfurt and Paris from 1985 to 2002 were evaluated concerning incidence, demographics and surgical aspects. RESULTS: From 1985 to 2002, 312 body pushers and 4,660 body packers were identified. The sex ratio was 1:1. Sixty-four "mules" (1.4%) developed life-threatening symptoms of cocaine overdose after the rupture of a container. In 20 patients, an emergency laparotomy was performed and the containers were removed; all of these patients survived. Forty-four body packers died before surgical treatment could be performed. Only one body pusher required medical attention. CONCLUSION: Cocaine overdose can be life-threatening. If the cause is the rupture of a container in a body packer, the only possible treatment is immediate laparotomy for the removal of the container.