Volatilomic profiles of gastric juice in gastric cancer patients.

Volatilomics is a powerful tool capable of providing novel biomarkers for the diagnosis of gastric cancer. The main objective of this study was to characterize the volatilomic signatures of gastric juice in order to identify potential alterations induced by gastric cancer. Gas chromatography with mass spectrometric detection, coupled with headspace solid phase microextraction as the pre-concentration technique, was used to identify volatile organic compounds (VOCs) released by gastric juice samples collected from 78 gastric cancer patients and two cohorts of controls (80 and 96 subjects) from four different locations (Latvia, Ukraine, Brazil, and Colombia). 1440 distinct compounds were identified in samples obtained from patients and 1422 in samples provided by controls. However, only 6% of the VOCs exhibited an incidence higher than 20%. Amongst the volatiles emitted, 18 showed differences in their headspace concentrations above gastric juice of cancer patients and controls. Ten of these (1-propanol, 2,3-butanedione, 2-pentanone, benzeneacetaldehyde, 3-methylbutanal, butylated hydroxytoluene, 2-pentyl-furan, 2-ethylhexanal, 2-methylpropanal and phenol) appeared at significantly higher levels in the headspace of the gastric juice samples obtained from patients; whereas, eight species showed lower abundance in patients than found in controls. Given that the difference in the volatilomic signatures can be explained by cancer-related changes in the activity of certain enzymes or pathways, the former set can be considered potential biomarkers for gastric cancer, which may assist in developing non-invasive breath tests for the diagnosis of this disease. Further studies are required to elucidate further the mechanisms that underlie the changes in the volatilomic profile as a result of gastric cancer.

Consumption of processed and ultra-processed foods by patients with stomach adenocarcinoma: a multicentric case-control study in the Amazon and southeast regions of Brazil.

PURPOSE: There is limited information about the dietary habits associated with stomach adenocarcinoma in the Brazilian population, so our purpose is to analyze the consumption of processed and ultra-processed foods by patients with stomach adenocarcinoma in Brazil. METHODS: A multicentric hospital-based case-control study was conducted in São Paulo (southeastern region) and Belém (Amazon region) of Brazil with 1,045 individuals, both sexes, between 18 and 75 years old. In São Paulo, there were 214 cases with stomach adenocarcinoma and 150 controls patients submitted to stomach endoscopy named as Group I (without any pre-malignant gastric disease) and the Healthy Controls (Group 2) comprised 401 individuals matched by age and sex from the prevention unit at A.C .Camargo Cancer Center. In Belém, it has two groups one are cases 140 and second 140 hospital controls, recruited in outpatient clinics. Lifestyle and food frequency questionnaires (FFQ) were administered in cases and controls in both places. Univariate and multivariable binomial logistic regression analyses were performed. RESULTS: In São Paulo, cases reported two times greater consumption of processed meat (adjusted OR 2.56, 95% CI 1.32-4.96) and of sweets (≥ 80 g/day) than Group 1 (endoscopic controls) (adjusted OR 2.25, 95% CI 1.21-4.18). Compared with Group 2, processed food consumption (≥ 44 g/day) as well as ≥ 44 g/day of salted bread increased the odds of having stomach adenocarcinoma (adjusted OR 2.96, 95% CI 1.82-4.81 and adjusted OR 2.03, 95% CI 1.30-3.18), respectively. In Belém, individuals who reported consuming ≥ 166 g/day of fried and roasted meat and fish were more likely to have stomach adenocarcinoma (adjusted OR 2.21, 95% CI 1.13-4.30). CONCLUSIONS: In both cities, consumption of processed and ultra-processed foods, especially salted bread, yellow cheese, fried and roasted meats, fish fried, processed meat, and sweets, was independently associated with the chance of having stomach adenocarcinoma.

Evaluation of Bacteria and Fungi DNA Abundance in Human Tissues.

Whereas targeted and shotgun sequencing approaches are both powerful in allowing the study of tissue-associated microbiota, the human: microorganism abundance ratios in tissues of interest will ultimately determine the most suitable sequencing approach. In addition, it is possible that the knowledge of the relative abundance of bacteria and fungi during a treatment course or in pathological conditions can be relevant in many medical conditions. Here, we present a qPCR-targeted approach to determine the absolute and relative amounts of bacteria and fungi and demonstrate their relative DNA abundance in nine different human tissue types for a total of 87 samples. In these tissues, fungi genomes are more abundant in stool and skin samples but have much lower levels in other tissues. Bacteria genomes prevail in stool, skin, oral swabs, saliva, and gastric fluids. These findings were confirmed by shotgun sequencing for stool and gastric fluids. This approach may contribute to a more comprehensive view of the human microbiota in targeted studies for assessing the abundance levels of microorganisms during disease treatment/progression and to indicate the most informative methods for studying microbial composition (shotgun versus targeted sequencing) for various samples types.

ENDOSCOPIC CHARACTERISTICS OF PATIENTS WITH COMPLETE PATHOLOGICAL RESPONSE AFTER NEOADJUVANT CHEMOTHERAPY FOR GASTRIC AND ESOPHAGOGASTRIC JUNCTION ADENOCARCINOMAS.

BACKGROUND: Gastric and esophagogastric junction adenocarcinoma are responsible for approximately 13.5% of cancer-related deaths. Given the fact that these tumors are not typically detected until they are already in the advanced stages, neoadjuvancy plays a fundamental role in improving long-term survival. Identification of those with complete pathological response (pCR) after neoadjuvant chemotherapy (NAC) is a major challenge, with effects on organ preservation, extent of resection, and additional surgery. There is little or no information in the literature about which endoscopic signs should be evaluated after NAC, or even when such re-evaluation should occur. AIM: To describe the endoscopic aspects of patients with gastric and esophagogastric junction adenocarcinomas who underwent NAC and achieved pCR, and to determine the accuracy of esophagogastroduodenoscopy (EGD) in predicting the pCR. METHODS: A survey was conducted of the medical records of patients with these tumors who were submitted to gastrectomy after NAC, with anatomopathological result of pCR. RESULTS: Twenty-nine patients were identified who achieved pCR after NAC within the study period. Endoscopic responses were used to classify patients into two groups: G1-endoscopic findings consistent with pCR and G2-endoscopic findings not consistent with pCR. Endoscopic evaluation in G1 was present in an equal percentage (47.4%; p=0.28) in Borrmann classification II and III. In this group, the predominance was in the gastric body (57.9%; p=0.14), intestinal subtype with 42.1% (p=0.75), undifferentiated degree, 62.5% (p=0.78), Herb+ in 73.3% (p=0.68). The most significant finding, however, was that the time interval between NAC and EGD was longer for G1 than G2 (24.4 vs. 10.2 days, p=0.008). CONCLUSION: EGD after NAC seems to be a useful tool for predicting pCR, and it may be possible to use it to create a reliable response classification. In addition, the time interval between NAC and EGD appears to significantly influence the predictive power of endoscopy for pCR.

Endoscopic characteristics of patients with complete pathological response after neoadjuvant chemotherapy for gastric and esophagogastric junction adenocarcinomas / Características endoscópicas de pacientes com resposta patológica completa após quimioterapia neoadjuvante para adenocarcinomas gástricos e de junção esofagogástrica

ABSTRACT Background: Gastric and esophagogastric junction adenocarcinoma are responsible for approximately 13.5% of cancer-related deaths. Given the fact that these tumors are not typically detected until they are already in the advanced stages, neoadjuvancy plays a fundamental role in improving long-term survival. Identification of those with complete pathological response (pCR) after neoadjuvant chemotherapy (NAC) is a major challenge, with effects on organ preservation, extent of resection, and additional surgery. There is little or no information in the literature about which endoscopic signs should be evaluated after NAC, or even when such re-evaluation should occur. Aim: To describe the endoscopic aspects of patients with gastric and esophagogastric junction adenocarcinomas who underwent NAC and achieved pCR, and to determine the accuracy of esophagogastroduodenoscopy (EGD) in predicting the pCR. Methods: A survey was conducted of the medical records of patients with these tumors who were submitted to gastrectomy after NAC, with anatomopathological result of pCR. Results: Twenty-nine patients were identified who achieved pCR after NAC within the study period. Endoscopic responses were used to classify patients into two groups: G1-endoscopic findings consistent with pCR and G2-endoscopic findings not consistent with pCR. Endoscopic evaluation in G1 was present in an equal percentage (47.4%; p=0.28) in Borrmann classification II and III. In this group, the predominance was in the gastric body (57.9%; p=0.14), intestinal subtype with 42.1% (p=0.75), undifferentiated degree, 62.5% (p=0.78), Herb+ in 73.3% (p=0.68). The most significant finding, however, was that the time interval between NAC and EGD was longer for G1 than G2 (24.4 vs. 10.2 days, p=0.008). Conclusion: EGD after NAC seems to be a useful tool for predicting pCR, and it may be possible to use it to create a reliable response classification. In addition, the time interval between NAC and EGD appears to significantly influence the predictive power of endoscopy for pCR.

RESUMO Racional: O adenocarcinoma gástrico e da junção esofagogástrica é responsável por aproximadamente 13,5% das mortes relacionadas ao câncer. Dado que esses tumores não são normalmente detectados até que já estejam em estágios avançados, a neoadjuvância desempenha um papel fundamental na melhoria da sobrevida em longo prazo. A identificação daqueles com resposta patológica completa (pCR) após a quimioterapia neoadjuvante (NAC) é um grande desafio, com efeitos na preservação do órgão, extensão da ressecção e cirurgia adicional. Há pouca ou nenhuma informação na literatura sobre quais sinais endoscópicos devem ser avaliados após a NAC, ou mesmo quando essa reavaliação deve ocorrer. Objetivo: Descrever os aspectos endoscópicos de pacientes com adenocarcinoma gástrico e da junção esofagogástrica que foram submetidos à quimioterapia neoadjuvante e alcançaram pCR, e determinar a acurácia da esofagogastroduodenoscopia (EGD) em predizer a pCR. Métodos: Foram revisados os prontuários de pacientes submetidos à gastrectomia subtotal e total após NAC, com resultado anatomopatológico de pCR. Resultados: Vinte e nove pacientes que alcançaram pCR após NAC foram identificados no período estudado. As respostas endoscópicas foram usadas para classificar os pacientes em dois grupos: G1- achados endoscópicos consistentes com pCR, G2 - achados endoscópicos não consistentes com pCR. A avaliação endoscópica no G1 esteve presente em igual percentual (47,4%; p=0,28) na classificação de Borrmann II e III. Nesse grupo, a predominância foi no corpo gástrico (57,9%; p=0,14), subtipo intestinal com 42,1% (p=0,75), grau indiferenciado, 62,5% (p=0,78), Herb+ em 73,3% (p=0,68). O achado mais significativo, no entanto, foi que o intervalo de tempo entre NAC e EGD foi maior para G1 do que G2 (24,4 vs. 10,2 dias, p=0,008). Conclusão: A EGD após NAC, nessa pesquisa, sugeriu ser método útil para prever pCR, mediante uma classificação de resposta confiável. Além disso, o intervalo de tempo entre NAC e EGD parece influenciar significativamente a sua capacidade preditiva de diagnosticar a pCR.

Identification of DNA mutations in gastric washes from gastric adenocarcinoma patients: Possible implications for liquid biopsies and patient follow-up.

Whereas cancer patients have benefited from liquid biopsies, the scenario for gastric adenocarcinoma (GAC) is still dismal. We used next-generation deep sequencing of TP53-a highly mutated and informative gene in GAC-to assess mutations in tumor biopsies, plasma (PL) and stomach fluids (gastric wash-GW). We evaluated their potential to reveal tumor-derived mutations, useful for monitoring mutational dynamics at diagnosis, progression and treatment. Exon-capture libraries were constructed from 46 patients including tumor biopsies, GW and PL pre and post-treatment (196 samples), with high vertical coverage >8,000×. At diagnosis, we detected TP53 mutations in 15/46 biopsies (32.6%), 7/46 GW- (15.2%) and 6/46 PL-samples (13%). Biopsies and GW were concordant in 38/46 cases (82.6%) for the presence/absence of mutations and, furthermore, four GW-exclusive mutations were identified, suggesting tumor heterogeneity. Considering the combined analysis of GW and PL, TP53 mutations found in biopsies were also identified in 9/15 (60%) of cases, the highest detection level reported for GAC. Our study indicates that GW could be useful to track DNA alterations, especially if anchored to a comprehensive gene-panel designed for this malignancy.

Genomics and epidemiology for gastric adenocarcinomas (GE4GAC): a Brazilian initiative to study gastric cancer

Gastric cancer (GC) is the fifth most common type of cancer worldwide with high incidences in Asia, Central, and South American countries. This patchy distribution means that GC studies are neglected by large research centers from developed countries. The need for further understanding of this complex disease, including the local importance of epidemiological factors and the rich ancestral admixture found in Brazil, stimulated the implementation of the GE4GAC project. GE4GAC aims to embrace epidemiological, clinical, molecular and microbiological data from Brazilian controls and patients with malignant and pre-malignant gastric disease. In this letter, we summarize the main goals of the project, including subject and sample accrual and current findings

Comparative Study between Plastic and Metallic Stents for Biliary Decompression in Patients with Distal Biliary Obstruction.

This paper presents a retrospective comparison of plastic versus metallic stents in the drainage of malignant distal biliary obstructions. We compared single plastic stents (SPS), multiple plastic stents (MPS), and metallic stents (SEMS) regarding clinical decrease of TB < 2.0 mg/dL, long-term patency, and adverse event. 58 patients (38 women) with MDBO were included. Diagnoses were 44 pancreatic adenocarcinoma (74.6%), 9 metastasis (15.5%), 3 pancreatic neuroendocrine tumors (5.1%), and 2 adenocarcinoma in the major papilla (3.4%). The number of patients included in the SPS, MPS, and SEMS was 17, 6, and 35, respectively. Comparing the survival curves with respect to obstruction, we observed a lower mean permeability of the SPS compared to that of the MPS with p < 0.003 and of the SEMS group (p < 0.01). There was no statistical difference between the use of MPS, despite the small number of patients compared to the use of SEMS (p < 0.13) to reach the satisfactory levels of bilirubin.

Alternative technique in secondary tracheoesophageal puncture using flexible endoscope and overtube in patients with difficult post-laryngectomy abnormalities

Background: Functional speech rehabilitation after total laryngectomy remains one of the most challenging issues in head and neck multidisciplinary care. Tracheoesophageal puncture for voice prosthesis insertion performed as a secondary procedure with a rigid esophagoscope and trocar can be technically difficult in certain patients due to post-treatment cervical abnormalities, such as reduced hyperextension, stenosis, and trismus. Methods: This study presents an improved method of secondary tracheoesophageal prosthesis insertion using a flexible endoscope in association with a plastic pliable overtube to keep the virtual esophageal lumen open. By this method, the puncture can be performed easily and safely with the avoidance of unexpected lesions. Results: From 2005 to 2015, 12 (16,9%) out of 71 patients who underwent secondary voice prosthesis placement at our institution required this alternative technique due to anatomical alterations that hindered the execution of the procedure following the standard technique. Conclusion: The procedure was successfully performed in all patients with no related complications (AU)

Cadherin-catenin adhesion system and mucin expression: a comparison between young and older patients with gastric carcinoma.

BACKGROUND: Young patients are thought to develop gastric carcinomas with a molecular genetic profile that is distinct from that of gastric carcinomas occurring at a later age. The aim of this study was to compare the clinicopathological features and expression patterns of the markers E-cadherin and beta-catenin, and mucins (MUC1, MUC2, MUC5AC, and MUC6) in young and older patients. METHODS: The clinicopathological features and overall survival data of 62 young patients (age 40 years). A tissue microarray method and immunohistochemistry were used in order to analyze marker expression in paraffin-embedded tissue blocks obtained from both groups. RESULTS: The young group presented a higher percentage of diffuse-type tumors in comparison to the older group (P<0.01). The rates of positivity for E-cadherin and beta-catenin membranous expression patterns and mucin (MUC2, MUC5AC and MUC6) positivity were higher in the young group (P<0.01). Although young patients showed a lower frequency of alterations in marker expression and had significantly better survival rates than the older patients, neither age nor the marker expression pattern were found to be independent prognostic factors of survival. Only stage, tumor size, and tumor location persisted as prognostic factors for patients with gastric cancer. CONCLUSION: Biological markers of cellular adhesion and gastric differentiation were differently expressed in young and older patients. Our findings support the hypothesis that young patients develop carcinomas with a different genetic pathway compared to the pathway of tumors occurring at a later age, and we suggest further investigations to assess the prognostic relevance of the markers to specific subgroups.

Expression profile of malignant and nonmalignant lesions of esophagus and stomach: differential activity of functional modules related to inflammation and lipid metabolism.

Adenocarcinomas of stomach and esophagus are frequently associated with preceding inflammatory alterations of the normal mucosa. Whereas intestinal metaplasia of the gastric mucosa is associated with higher risk of malignization, Barrett's disease is a risk factor for adenocarcinoma of the esophagus. Barrett's disease is characterized by the substitution of the squamous mucosa of the esophagus by a columnar tissue classified histopathologically as intestinal metaplasia. Using cDNA microarrays, we determined the expression profile of normal gastric and esophageal mucosa as well as intestinal metaplasia and adenocarcinomas from both organs. Data were explored to define functional alterations related to the transformation from squamous to columnar epithelium and the malignant transformation from intestinal metaplasia to adenocarcinomas. Based on their expression profile, adenocarcinomas of the esophagus showed stronger correlation with intestinal metaplasia of the stomach than with Barrett's mucosa. Second, we identified two functional modules, lipid metabolism and cytokine, as being altered with higher statistical significance. Whereas the lipid metabolism module is active in samples representing intestinal metaplasia and inactive in adenocarcinomas, the cytokine module is inactive in samples representing normal esophagus and esophagitis. Using the concept of relevance networks, we determined the changes in linear correlation of genes pertaining to these two functional modules. Exploitation of the data presented herein will help in the precise molecular characterization of adenocarcinoma from the distal esophagus, avoiding the topographical and descriptive classification that is currently adopted, and help with the proper management of patients with Barrett's disease.

Molecular classifiers for gastric cancer and nonmalignant diseases of the gastric mucosa.

High incidence of gastric cancer-related death is mainly due to diagnosis at an advanced stage in addition to the lack of adequate neoadjuvant therapy. Hence, new tools aimed at early diagnosis would have a positive impact in the outcome of the disease. Using cDNA arrays having 376 genes either identified previously as altered in gastric tumors or known to be altered in human cancer, we determined expression signature of 99 tissue fragments representing normal gastric mucosa, gastritis, intestinal metaplasia, and adenocarcinomas. We first validated the array by identifying molecular markers that are associated with intestinal metaplasia, considered as a transition stage of gastric adenocarcinomas of the intestinal type as well as markers that are associated with diffuse type of gastric adenocarcinomas. Next, we applied Fisher's linear discriminant analysis in an exhaustive search of trios of genes that could be used to build classifiers for class distinction. Many classifiers could distinguish between normal and tumor samples, whereas, for the distinction of gastritis from tumor and for metaplasia from tumor, fewer classifiers were identified. Statistical validations showed that trios that discriminate between normal and tumor samples are powerful classifiers to distinguish between tumor and nontumor samples. More relevant, it was possible to identify samples of intestinal metaplasia that have expression signature resembling that of an adenocarcinoma and can now be used for follow-up of patients to determine their potential as a prognostic test for malignant transformation.