Absence of the Nonextension Sign as a Marker for Endoscopic Submucosal Dissection Suitability.

Early gastric cancer is defined as gastric cancer confined to the mucosa or submucosa, irrespective of lymph node metastasis. Endoscopic submucosal dissection is a standard treatment of early gastric cancer. The nonextension sign consists of a protrusion of the surrounding mucosa into the lumen, resembling a trapezoidal shape. This phenomenon occurs when massive submucosal invasion by a cancer increases the thickness and rigidity of the gastric wall and may be useful to differentiate between mucosal or microinvasive submucosal and invasive submucosal cancers. Our case demonstrates the usefulness of the absence of the conventional endoscopic nonextension sign as a marker to decide the adequate approach for mucosal lesions.

Predictive factors of lymphatic metastasis and evaluation of the Japanese treatment guidelines for endoscopic resection of early gastric cancer in a high-volume center in Perú.

Purpose: This study aimed to identify the predictive factors of lymph node metastasis (LNM) in patients with early gastric cancer (EGC) and to evaluate the applicability of the Japanese treatment guidelines for endoscopic resection in the western population. Methods: Five hundred-one patients with pathological diagnoses of EGC were included. Univariate and multivariate analyses were conducted to identify the predictive factors of LNM. EGC patients were distributed according to the indications for endoscopic resection of the Eastern guidelines. The incidence of LNM was evaluated in each group. Results: From 501 patients with EGC, 96 (19.2%) presented LNM. In 279 patients with tumors with submucosal infiltration (T1b), 83 (30%) patients had LNM. Among 219 patients who presented tumors > 3 cm, 63 (29%) patients had LNM. Thirty-one percent of patients with ulcerated tumors presented LMN (33 out of 105). In 76 patients and 24 patients with lymphovascular and perineural invasion, the percentage of LMN was 84% and 87%, respectively. In the multivariate analysis, a tumor diameter >3 cm, submucosal invasion, lymphovascular, and perineural invasion were independent predictors of LMN in EGC. No patient with differentiated, non-ulcerated mucosal tumors presented LNM regardless of tumor size. Three of 17 patients (18%) with differentiated, ulcerated mucosal tumors and ≤ 3 cm presented LNM. No LNM was evidenced in patients with undifferentiated mucosal tumors and ≤ 2 cm. Conclusions: The presence of LNM in Western EGC patients was independently related to larger tumors (>3 cm), submucosal invasion, lymphovascular and perineural invasion. The Japanese absolute indications for EMR are safe in the Western population. Likewise, Western patients with differentiated, non-ulcerated mucosal tumors, and larger than 2 cm are susceptible to endoscopic resection. Patients with undifferentiated mucosal tumors smaller than 2 cm presented encouraging results and ESD could be recommended only for selected cases.

Endoscopic Resection Versus Surgery in the Treatment of Early Gastric Cancer: A Systematic Review and Meta-Analysis.

Background and Aim: Endoscopic resection (ER) is the preferred approach to treat early gastric cancer (EGC) in patients without suspected lymph node involvement and that meet the criteria for ER. Surgery is a more aggressive treatment, but it may be associated with less recurrence and the need for reintervention. Previous meta-analyses comparing ER with surgery for EGC did not incorporate the most recent studies, making accurate conclusions not possible. Methods: This systematic review and meta-analysis aimed to examine complete resection, length of hospital stay (LOHS), adverse events (AEs), serious AEs, recurrence, 5-year overall survival (OS), and 5-year cancer-specific survival (CSS) in patients with EGC. Results: A total of 29 cohorts studies involving 20559 patients were included. The ER (n = 7709) group was associated with a lower incidence of AEs (RD = -0.07, 95%CI = -0.1, -0.04, p < 0.0001) and shorter LOHS (95% CI -5.89, -5.32; p < 0,00001) compared to surgery (n = 12850). However, ER was associated with lower complete resection rates (RD = -0.1, 95%CI = -0.15, -0.06; p < 0.00001) and higher rates of recurrence (RD = 0.07, 95%CI = 0.06; p < 0.00001). There were no significant differences between surgery and ER in 5-year OS (RD = -0.01, 95%CI = -0.04, 0.02; p = 0.38), 5-year CSS (RD = 0.01, 95%CI = 0.00, 0.02; p < 0.17), and incidence of serious AEs (RD = -0.03, 95%CI = -0.08, 0.01; p = 0.13). Conclusions: ER and surgery are safe and effective treatments for EGC. ER provides lower rates of AEs and shorter LOHS compared to surgery. Although ER is associated with lower complete resection rates and a higher risk of recurrence, the OS and CSS were similar between both approaches. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42021255328.

Risk of lymph node metastasis in early gastric cancer and indications for endoscopic resection: is it worth applying the east rules to the west?

BACKGROUND: Early gastric cancers are associated with lymph node metastasis (LNM) in 15% of cases. Risk factors for LNM are well established in Eastern countries. Less invasive treatments, such as endoscopic or surgical laparoscopic resection, are well accepted in Eastern countries and a matter of intense debate in the West, were indications for such treatments are still contested The objective of the study is to determine risk factors related to LNM and to validate endoscopic resection indications. METHODS: The study was a retrospective cohort of 178 patients with early gastric cancer who underwent gastrectomy. Clinical and pathological factors were analyzed. The new rules of ER from JGCA were applied to the studied cohort. RESULTS: LNM was present in 13.48% of the cases, 3.96% (3/76) in T1a tumors and 20.58% (21/102) in T1b tumors. In univariate analysis ulceration (p = 0.04), differentiation grade (p = 0.04), submucosal invasion (p = 0.001), lymphatic invasion (p < 0.001), and vascular invasion (p < 0.001) were associated with LNM. In multivariate analysis, differentiation grade (p = 0.005) and submucosal invasion (p = 0.005) were independent risk factors. One patient classified in the expanded criteria group and seven from the relative criteria group had LNM. There were no LNM for undifferentiated mucosal lesions without ulceration. CONCLUSIONS: Undifferentiated tumors and submucosal invasion are risks factors associated with LNM in early gastric cancer in our study. Endoscopic Resection or less invasive and radical surgical treatments are an option to be carefully considered.

Desarrollo de la técnica de disección submucosa endoscópica en cáncer gástrico incipiente: primeros cincuenta casos de un cirujano / Development of endoscopic submucosal dissection for early gastric cancer: fifty first cases of a surgeon

Resumen Introducción: El cáncer gástrico es un problema de salud en Chile y su mal pronóstico global se explica por un diagnóstico en etapas avanzadas. El cáncer gástrico incipiente (CGI) se asocia a buen pronóstico oncológico y la disección submucosa endoscópica (DSE) como alternativa de tratamiento ha demostrado ser comparable al estándar quirúrgico. Objetivo: Describir la experiencia y resultados de un cirujano en pacientes con CGI sometidos a DSE. Materiales y Método: Estudio retrospectivo que incluyó a los pacientes sometidos a DSE por CGI entre mayo de 2015 y marzo de 2019. Se tabuló información demográfica, datos perioperatorios y del seguimiento obtenidos del registro institucional. Se utilizó estadística descriptiva. Resultados: Se realizaron 52 DSE por CGI en el período analizado. La resección en bloque se logró en un 96% de los casos. La morbilidad alcanzó el 2%, no se registró mortalidad postoperatoria. 98% de las resecciones en bloque fueron consideradas R0 y un 86% de ellas cumplieron estándares de curación. La mediana de seguimiento es de 19 meses y la sobrevida específica por cáncer gástrico y libre de recurrencia alcanza el 100%. Discusión: La DSE es una técnica con potencial curativo en pacientes con CGI, presentando mejores resultados en términos de morbimortalidad, calidad de vida y es comparable a la cirugía en el pronóstico oncológico. Los resultados presentados son concordantes con la literatura y apoyan la implementación de la técnica para el tratamiento del CGI.

Introduction: Gastric cancer is a serious health problem in Chile and its poor prognosis is explained by usual diagnosis in advanced stages. Early gastric cancer (EGC) is associated with good oncological prognosis and endoscopic submucosal dissection (ESD) as its treatment has shown to be comparable to the surgical standard. Aim: Describe the experience and results of a surgeon in patients with EGC undergoing ESD. Materials and Method: Retrospective study including patients undergoing ESD for EGC between May 2015 and March 2019. Demographic information, perioperative and follow-up data obtained from the institutional registry were tabulated. Descriptive statistics was used. Results: 52 ESD were performed per EGC in the analyzed period. En bloc resection was achieved in 96% of cases. Morbidity reached 2% and no postoperative mortality was recorded. 98% of the en bloc resections were considered R0 and 86% of them met healing standards. The median follow-up is 19 months and the specific survival due to gastric cancer and recurrence-free rates reach 100%. Discussion: ESD is a technique with curative potential in patients with EGC, presenting better results in terms of morbidity and mortality, quality of life and is comparable to surgery in the oncological prognosis. The results presented are consistent with the literature and support the implementation of the technique for the treatment of EGC.

Systematic alphanumeric-coded endoscopy versus chromoendoscopy for the detection of precancerous gastric lesions and early gastric cancer in subjects at average risk for gastric cancer. / Aplicación de la endoscopia sistemática alfanumérica codificada más cromoendoscopia para la detección de lesiones precancerosas gástricas y cáncer gástrico temprano en sujetos con riesgo promedio de cáncer gástrico.

INTRODUCTION AND AIMS: Gastric cancer is one of the main causes of cancer worldwide, but there is currently no global screening strategy for the disease. Endoscopy is the screening method of choice in some Asian countries, but no standardized technique has been recognized. Systematic alphanumeric-coded endoscopy can increase gastric lesion detection. The aim of the present article was to compare the usefulness of systematic alphanumeric-coded endoscopy with conventional endoscopy for the detection of premalignant lesions and early gastric cancer in subjects at average risk for gastric cancer. MATERIALS AND METHODS: A cross-sectional, comparative, prospective, randomized study was conducted on patients at average risk for gastric cancer (40-50 years of age, no history of H. pylori infection, intestinal metaplasia, gastric atrophy, or gastrointestinal surgery). Before undergoing endoscopy, the patients had gastric preparation (200mg of oral acetylcysteine or 50mg of oral dimethicone). Conventional chromoendoscopy was performed with indigo carmine dye for contrast enhancement. RESULTS: Fifty consecutive cases (mean age 44.4 ± 3.34 years, 60% women, BMI 27.6 ± 5.82 kg/m2) were evaluated. Endoscopic imaging quality was satisfactory in all the cases, with no differences between methods (p = 0.817). The detection rate of premalignant lesions and early gastric cancer was 14% (6 cases of intestinal metaplasia and one case of gastric adenocarcinoma). Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 100, 95, 80, 100 and 96%, respectively, for systematic alphanumeric-coded endoscopy, and 100, 45, 20, 100, and 52%, respectively, for conventional endoscopy. Lesion detection through systematic alphanumeric-coded endoscopy was superior to that of conventional endoscopy (p = 0.003; OR = 12). CONCLUSION: Both techniques were effective, but systematic alphanumeric-coded endoscopy significantly reduced the false positive rate.

Risk Factors for Lymph Node Metastasis in Western Early Gastric Cancer After Optimal Surgical Treatment.

BACKGROUND: Lymph node metastasis (LNM) has a strong influence on the prognosis of patients with early gastric cancer (EGC). As minimally invasive treatments are considered appropriate for EGC, and lymphadenectomy may be restricted or even eliminated in some cases; it is imperative to identify the main risk factors for LNM to individualize the therapeutic approach. This study aims to evaluate the risk factors for LNM in EGC and to determine the adequacy of the endoscopic resection criteria in a western population. METHODS: EGC patients who underwent gastrectomy with lymphadenectomy were retrospectively analyzed utilizing a prospective database. The clinicopathological variables were assessed to determine which factors were associated to LNM. RESULTS: Among 474 enrolled patients, 105 had EGC (22.1%). LNM occurred in 13.3% of all EGC (10% T1a; 15.4% T1b). Tumor size, venous, lymphatic, and perineural invasions were confirmed as independent predictors of LNM by multivariate analysis. Expanded criteria were safely adopted only in selected cases, and 13.6% of patients who matched expanded indication had LNM. CONCLUSIONS: Tumor size, venous, lymphatic, and perineural invasions were associated with LNM and should be considered as surrogate markers for surgical treatment of EGC. Expanded criteria for endoscopic resection can be safely adopted only in selected cases.

Cáncer gástrico incipiente gigante: reporte de un caso / A case report: Giant early gastric cancer

Resumen Introducción: El cáncer gástrico es la primera causa de muerte por cáncer, en hombres, en Chile, siendo el adenocarcinoma la variante más frecuente. Caso clínico: Reportamos el caso de un cáncer gástrico incipiente gigante de 7,2 cm en un hombre de 74 años tratado en la Clínica INDISA en Santiago de Chile. El paciente fue sometido exitosamente a una gastrectomía total con linfoadenectomía D2 y esófago-yeyuno anastomosis en Y de Roux. La histología evidenció un adenocarcinoma bien diferenciado, polipoide, invasivo hasta la submucosa, sin compromiso ganglionar. A los 5 años de su cirugía, el paciente se encuentra asintomático y sin recidiva tumoral.

Abstract Introduction: The gastric cancer is the first cause of death from cancer, in men, in Chile, being the adenocarcinoma the most frequent variant. Clinical case: We report the case of a large early gastric cancer of 7.2 cm in a 74-year-old man who was treated in INDISA Clinic in Santiago, Chile. A total gastrectomy with D2 lymphadenectomy with End-to-Side esophagojejunostomy in a Roux-en-Y anastomosis was successfully performed. The histology showed a polypoid well differentiated adenocarcinoma infiltrating up to the submucosa without regional lymph node involvement. Five years after the surgery, he remains asymptomatic and without tumor recurrence.

¿Por qué no diagnosticamos el cáncer gástrico incipiente? ¿Cómo podemos mejorar? / Why do we fail in the diagnosis of early gastric cancer? How can we improve?

Detection and treatment of gastric cancer (GC) in early stages is the most effective approach for improving prognosis. Patients with early gastric cancer (EGC), defined as a type of cancer affecting only mucosa and submucosa, has a good prognosis in the long-term, and if some criteria are met, endoscopic therapy is curative. Unfortunately EGC diagnosis is rare, except in case of some Asian countries, where more than 50% of tumors are diagnosed in this stage. In Japan, the main technique for early diagnosis is opportunistic screening, i.e. endoscopy performed for different reasons. Some of the factors that affect endoscopic diagnose include: characteristics of the lesion (some cases slight changes in color or in the surface, a location that is difficult to detect, except in retro view); elements associated with the endoscopic technique (lesions hidden underneath gastric contents, non-systematic visualization, not enough time for exploration); and early access to the procedure (long waiting lists, lack of clinic or epidemiology screening criteria, lack of risk-stratification looking for pre-malignant lesions to establish endoscopic follow-up). Know and act upon the mentioned factors is a path that has proven to improve EGC diagnosis and therefore, improve prognosis.

Detectar y tratar el cáncer gástrico (CG) en una etapa inicial constituye la estrategia más efectiva para mejorar el pronóstico de esta patología. Pacientes con CG incipiente (CGI), definido como el que compromete sólo la mucosa y la submucosa, tienen un muy buen pronóstico a largo plazo y si se cumplen algunos criterios, el tratamiento endoscópico es curativo. Desgraciadamente el diagnóstico de CGI es infrecuente en todo el mundo, a excepción de algunos países asiáticos donde más de la mitad de los tumores se diagnostican en esta etapa. En Japón la principal vía por la que se realiza este diagnóstico precoz es mediante el tamizaje oportunista, es decir, la endoscopia que se realiza de manera cotidiana por diferentes motivos. Dentro de los factores que afectan la capacidad diagnóstica de la endoscopia destacan: las características de la lesión (algunos casos con discretos cambios de color o superficie, ubicación habitualmente en áreas de mejor visualización en retrovisión); factores asociados a la técnica endoscópica (contenido gástrico que puede ocultar lesiones, visualización no sistemática, tiempo insuficiente de exploración); y el acceso oportuno a ella (largas listas de espera, falta de criterios de selección clínicos o epidemiológicos, falta de estratificación del riesgo mediante la búsqueda de lesiones premalignas para definir intervalos de seguimiento endoscópico). Conocer y actuar sobre los factores descritos es un camino que ha demostrado su utilidad en mejorar el diagnóstico del CGI y así mejorar su pronóstico.

Clinical relevance of aberrant polypoid nodule scar after endoscopic submucosal dissection.

AIM: To describe a series of patients with aberrant polypoid nodule scar developed after gastric endoscopic submucosal dissection (ESD), and to discuss its pathogenesis and clinical management. METHODS: We reviewed retrospectively the endoscopic database of two academic institutions located in Brazil and Japan and searched for all patients that underwent ESD to manage gastric neoplasms from 2003 to 2015. The criteria for admission in the study were: (1) successful en bloc ESD procedure with R0 and curative resection confirmed histologically; (2) postoperative endoscopic examination with identification of a polypoid nodule scar (PNS) at ESD scar; (3) biopsies of the PNS with hyperplastic or regenerative tissue, reviewed by two independent experienced gastrointestinal pathologists, one from each Institution. Data were examined for patient demographics, Helicobacter pylori status, precise neoplastic lesion location in the stomach, tumor size, histopathological assessment of the ESD specimen, and postoperative information including medical management, endoscopic and histological findings, and clinical outcome. RESULTS: A total of 14 patients (10 men/4 women) fulfilled the inclusion criteria and were enrolled in this study. One center contributed with 8 cases out of 60 patients (13.3%) from 2008 to 2015. The second center contributed with 6 cases (1.7%) out of 343 patients from 2003 to 2015. Postoperative endoscopic follow-up revealed similar findings in all patients: A protruded polypoid appearing nodule situated in the center of the ESD scar surrounded by convergence of folds. Biopsies samples were taken from PNS, and histological assessment revealed in all cases regenerative and hyperplastic tissue, without recurrent tumor or dysplasia. Primary neoplastic lesions were located in the antrum in 13 patients and in the angle in one patient. PNS did not develop in any patient after ESD undertaken for tumors located in the corpus, fundus or cardia. All patients have been followed systematically on an annual basis and no malignant recurrence in the ESD scar has been identified (mean follow-up period: 45 mo). CONCLUSION: PNS may occur after ESD for antral lesions and endoscopically look concerning, especially for the patient or the family doctor. However, as long as curative R0 resection was successfully achieved and histology demonstrates only regenerative and hyperplastic tissue, PNS should be viewed as a benign alteration that does not require any type of intervention, other than endoscopic surveillance.

Disección submucosal endoscópica en cáncer gástrico temprano: Experiencia inicial / Endoscopic submucosal dissection in early gastric cancer: Initial experience

La disección submucosal endoscópica es una técnica endoluminal que nos permite resecciones amplias en un solo bloque en el tratamiento endoscópico del cáncer gástrico temprano.En este trabajo se presenta la experiencia inicial en la aplicación de la disección submucosal endoscópica en el tratamiento minimamente invasivo del cáncer gástrico temprano. Realizamos este procedimiento en 21 casos de cáncer gástrico temprano Y un caso de adenoma plano con displasia de bajo grado.La edad promedio de los pacientes fue de 67 años. Macroscópicamente 11 casos fueron Tipo IIc, 9 casos de cáncer gástrico temprano Tipo IIa y el otro caso fue una forma combinada Tipo IIa+II. 14 casos estaban localizados en antro próximal y 8 casos en cuerpo gástrico.21 casos fueron resecados en un solo bloque. Hubo una perforación y observamos hemorragia durante 7 casos que fueron controladas por vía endoscópica.

Endoscopic submucosal dissection (ESD) is a new endoluminal endoscopic procedure that allowed resection for early gastric cancer(EGC) in one bloc. In this paper we present 21 cases of EGC and one case of flat adenoma treated by ESD in our institution.Median age of our patients was 67 years.Macroscopically 11 cases were Tipe IIC, 9 case was Tipe IIa and the other case was Tipe IIa+IIc. According to localization 14 cases were located in the proximal antrum and 8 cases were located in gastric body .there was one perforation that it was solved by surgical procedure and we observed 7 cases with bleeding that were endosc opically treated.

Disección submucosa endoscópica en cáncer gástrico incipiente / Endoscopic submucosal dissection for early gastric cancer

Introduction: Endoscopic submucosal dissection (ESD) is nowadays the standard treatment for a subgroup of early gastric cancer with low risk of lymph node metastasis. This procedure has the advantage of achieving a higher percentage of negative margins and of allowing resections of larger tumors compared with the endoscopic mucosal resection (EMR) method, being less invasive compared with surgery. Aim: To analyze the postoperative outcomes, histology and overall survival of patients undergoing ESD in our center. Methods: Descriptive study. Data were collected from clinical records of patients undergoing ESD from January 2008 to June 2012. Results: 15 patients (8 males and 7 females, median age 70 years (45-88)) were included. The tumor was located at upper, middle and lower third in 2, 5 and 8 patients, respectively. Median tumor size was 13.5 mm (6-21). Most tumors were classified as type IIc. Among postoperative complications, there was 1 gastric bleeding and 3 gastric perforations. Hospital stay was 3 days (1-23). There was no mortality. There was one case of submucosal invasion. Negative margins were achieved in 86.7 percent. There was one deep and one lateral positive margin, managed by surgery and re-ESD, respectively. At 16 months (7-61) of median follow-up, overall survival was 100 percent. Tumor recurrence was observed in one patient at 51 months, was treated by surgery. Conclusion: ESD is a feasible technique in the minimally invasive management of early gastric cancer, allowing a high percentage of negative margins.

Introducción: La disección endoscópica de la submucosa (DES) es actualmente el tratamiento estándar en pacientes con cáncer gástrico incipiente y bajo riesgo de metástasis ganglionares, con la ventaja de obtener un mayor porcentaje de márgenes negativos que en la mucosectomía y ser menos invasivo que la cirugía. Objetivo: Analizar los resultados inmediatos, anatomía patológica y sobrevida alejada de los pacientes sometidos a DES en nuestro centro. Métodos: Estudio descriptivo. Revisión de los registros clínicos de pacientes con lesiones gástricas incipientes sometidos a DES entre enero de 2008 y junio de 2012. Resultados: Serie compuesta por 15 pacientes, 8 de sexo masculino. Mediana de edad 70 años (45-88). Ubicación tumoral: tercio superior en 2, tercio medio en 5 y tercio inferior en 8. La mediana de tamaño tumoral fue 13,5 mm (6-21). La mayoría fueron lesiones IIc. Dentro de las complicaciones postoperatorias, hubo 1 hemorragia digestiva tratada por endoscopia y 3 perforaciones gástricas tratadas quirúrgicamente (gastrorrafia). Mediana de hospitalización, 3 días (1-23). No se registró mortalidad post-procedimiento. Se obtuvieron bordes negativos en un 86,7 por ciento de los casos. Un paciente presentó margen profundo positivo, tratado mediante gastrectomía subtotal y otro presentó positividad en un margen lateral, manejado con una nueva DES. Mediana de seguimiento 16 meses (7-61), sin fallecidos por patología tumoral. Hubo 1 recurrencia tumoral (51 meses), tratada quirúrgicamente. Conclusión: La DES representa una alternativa en el manejo de las lesiones gástricas incipientes, permitiendo un alto porcentaje de márgenes negativos.

IMPROVED EXPERIMENTAL MODEL TO EVALUATE SUBMUCOSAL INJECTION SOLUTIONS FOR ENDOSCOPIC SUBMUCOSAL DISSECTION / MODELO EXPERIMENTAL PARA AVALIAÇÃO DO TEMPO DE PERMANÊNCIA DAS SOLUÇÕES DE INJEÇÃO PARA DISSECÇÃO ENDOSCÓPICA DE SUBMUCOSA GÁSTRICA

Background: Endoscopic submucosal dissection carries an increased risk of bleeding and perforation. The creation of a long lasting submucosal cushion is essential for the safe and complete removal of the lesion. There is not a suitable experimental model for evaluation of the durability of the cushioning effect of different solutions. Aim: To describe an improved experimental model to evaluate submucosal injection solutions. Methods: A total of four domestic pigs were employed to evaluate two different submucosal fluid solutions in the gastric submucosa. After midline laparotomy, the anterior gastric wall was incised from the gastric body to the antrum and its mucosal surface was exposed by flipping inside out the incised gastric wall. Two different solutions (10% mannitol and normal saline) were injected in the submucosa of the anterior wall of the distal gastric body. All submucosal cushions were injected until they reach the same size, standardized as 1.0 cm in height and 2.0 cm in diameter. A caliper and a ruler were employed to guarantee accuracy of the measurements. Results: All four animal experiments were completed. All submucosal cushions had the exact same size measured with caliper and a ruler. By using the mannitol solution, the mean duration of the submucosal cushion was longer than the saline solution: 20 and 22 min (mean, 21 min) vs 5 and 6 min (mean, 5.5 min) Conclusions: This experimental model is simple and evaluate the duration, size, and effect of the submucosal cushion, making it more reliable than other models that employ resected porcine stomachs or endoscopic images in live porcine models.

Racional: Sabe-se que os maiores riscos na ressecção endoscópica da submucosa são o sangramento e a perfuração. A criação de um coxim submucoso duradouro é essencial para a remoção da lesão completa e com segurança. Atualmente não se conhece um modelo experimental adequado para avaliação da durabilidade do coxim submucoso com diferentes soluções. Objetivo : Descrever um modelo experimental melhorado para avaliar soluções de injeção de submucosa. Métodos: Foram utilizados quatro porcos domésticos para avaliar dois tipos diferentes de soluções para injeção na submucosa gástrica. Após laparotomia mediana, a parede gástrica anterior foi aberta no sentido corpo-antro e sua superfície mucosa foi exposta por eversão da abertura gástrica. Dois tipos diferentes de solução (manitol a 10% e solução salina normal) foram injetados na submucosa da parede gástrica anterior de corpo distal. Todos os coxins submucosos foram injetados até que alcançassem o mesmo tamanho, padronizado como 1,0 cm de altura por 2,0 cm de diâmetro. Foram aplicados régua e compasso para garantir a acurácia das medidas. Resultados: O experimento foi completo nos quatro animais. Todos os coxins submucosos tinham o mesmo tamanho, medido com régua e compasso. Com o uso da solução de manitol, a duração média do coxim submucoso foi maior que a da solução salina: 20 e 22 min (média 21 min) vs 5 e 6 min (média 5,5 min). Conclusões: Este modelo experimental é simples e permite analisar duração, tamanho e efeito do coxim submucoso, tornando-se mais confiável que outros modelos que empregam estômagos ressecados de porcos ou imagens endoscópicas de modelos porcinos vivos.

Evolución durante 44 años de las característica morfológicas y sobrevida a largo plazo de 304 pacientes con cáncer gástrico incipiente / Early gastric cancer: a 44 years´ experience in 304 patients

Background: Early gastric cancer has a good long term prognosis. Aim: To report a 44 years’ experience in the management of early gastric cancer. Material and Methods: Retrospective and prospective analysis of patients with early gastric cancer, managed in three periods: group I from 1970 to 1989, group II from 1990 to 2003 and group III from 2004 to 2013. Tumor location in the stomach, macroscopic type, pathological type, lymph node involvement and long term survival were analyzed. Results: Three hundred four patients with a mean age of 62 years (170 males) were analyzed. Tumors were intramucosal and submucosal in 136 (45 percent) and 168 (55 percent) patients, respectively. Among group III proximal tumors anddiffuse pathological types weremore common. Five and 15 years survival were 88 and 72 percent, respectively. Conclusions: During the study period, tumor location and pathological types changed. Patients had high survival rates.

Introducción: El cáncer gástrico es una patología predominante en Chile. El carcinoma incipiente constituye una etapa inicial con muy buen pronóstico a largo plazo. El objetivo del presente estudio fue analizar las características morfológicas del carcinoma incipiente en 3 períodos de tiempo, con un período total de 44 años en un mismo centro, además de revisar la bibliografía nacional. Material y Método: Estudio mixto, tanto retrospectivo como prospectivo, desde 1970 hasta el año 2013, dividiendo a los pacientes en 3 grupos: grupo I desde 1970 hasta 1989, grupo II desde 1990 hasta 2003 y grupo III, desde 2004 hasta 2013. Se analizaron las siguientes variables: localización en el estómago, tipo macroscópico, tipo histológico, disección linfonodal y sobrevida a largo plazo. Para los cálculos estadísticos se empleó el Test de Fisher y c2. La sobrevida se analizó según el Test de Kaplan-Meier. Resultados: Hubo un total de 304 pacientes, que corresponden al 11,3 por ciento del total de pacientes resecados en el mismo período de tiempo. Hubo 136 pacientes con carcinoma mucoso (44,7 por ciento) y 168 con carcinoma submucoso (55,3 por ciento). Se observó un aumento estadísticamente significativo de la localización proximal del tumor. Hubo un aumento significativo del tipo histológico difuso en el III período analizado. La sobrevida a 15 años plazo fue mayor al 70 por ciento. Conclusiones: En 44 años se apreció un cambio en la localización del carcinoma incipiente y en el tipo histológico. La sobrevida alejada a 15 años es muy buena.

Endoscopia cooperativa con laparoscopia: una nueva alternativa para el manejo del cáncer gástrico temprano / Cooperative Endoscopic Laparoscopy: a new alternative for management of early gastric cancer

Usualmente, el cáncer temprano se trata con una resección submucosa; sin embargo, existen casos donde la lesión es muy grande, se ubica en un sitio muy difícil de disecar o tiene un patrón histológico muy agresivo, caso en el cual estaría indicada la gastrectomía. Este procedimiento es demasiado mutilante y da al paciente una mala calidad de vida y es ahí donde la endoscopia cooperativa con laparoscopia puede ser una nueva alternativa para el manejo de esta patología. En esta serie de casos presentamos la experiencia en nuestro hospital con esta técnica, mostrando cuáles son sus diferentes variables con el fin de que pueda ser aplicada en nuestro país.

Usually early gastric cancer is treated by submucosal resection, but for a case in which the lesion is very large, is located in a very difficult place for resection, or has a very aggressive histological pattern, a gastrectomy is indicated. This procedure is too mutilating and results in poor patient quality of life. For these cases cooperative endoscopic laparoscopy may be a new alternative for management of the condition. This series of cases presents our hospital’s experience with this technique and shows the variables faced with the procedure so that it can be applied elsewhere in our country.

Disección sub-mucosa endoscópica en cáncer gástrico incipiente / Endoscopic sub-mucosal dissection for early gastric cancer

Introduction: Gastric cancer is the leading cause of mortality in Chile and the survival rates are in direct relation with the stage of the disease. Early gastric cancer is defined as that confined to the mucosa or submucosa, regardless of the presence or absence of regional lymph node metastases and it is characterized for its great prognosis, with a survival rate of more than 90 percent at ten years of follow up. Endoscopic submucosal dissection is a technique described and developed in Japan that allows the endoscopic complete en-bloc resection of lesions of more than 2 cm with tumor cell-negative margins. Method: Databases (Pubmed, EBSCO, Cochrane) were reviewed under the terms "gastric cancer", "early gastric cancer", "endoscopic submucosal dissection". Results: The results of published series demonstrate survival rates comparable to standard surgery with less morbidity and without mortality. The present revision describes the endoscopic submucosal dissection technique in early gastric cancer, its indications, the results, the analysis of the resected pieces, the complications and the follow up of the patients. Conclusion: Endoscopic submucosal dissection is a feasible technique, with excellent oncologic results and low morbidity in selected patients.

Introducción: El cáncer gástrico es la primera causa de muerte por cáncer en Chile y la sobrevida se encuentra en directa relación con la etapa de la enfermedad. El cáncer gástrico incipiente se define como aquel cáncer limitado a la mucosa o sub-mucosa independiente del compromiso ganglionar y se caracteriza por su excelente pronóstico, con sobrevida mayor a 90 por ciento a 10 años de seguimiento. La disección sub-mucosa endoscópica es una técnica descrita y desarrollada en Japón que permite la resección en bloque y con márgenes negativos de tumores incipientes mayores a 2 cm por vía endoscópica. Método: Se realizó una búsqueda en las bases de datos (Pubmed, EBSCO, Cochrane) bajo las palabras clave: "gastric cáncer", "early gastric cáncer", "endoscopic submucosal dissection". Resultados: Los resultados de grandes series demuestran una sobrevida comparable a la cirugía clásica, con menor morbilidad y sin mortalidad asociada. La presente revisión describe la técnica de disección sub-mucosa endoscópica en cáncer gástrico incipiente, sus indicaciones, los resultados, el análisis de las piezas resecadas, las complicaciones y el modo de seguimiento de los pacientes. Conclusión: La disección sub-mucosa endoscópica es una alternativa válida, con buenos resultados a largo plazo en pacientes debidamente seleccionados.

Feasibility of endoscopic submucosal dissection for gastric and colorectal lesions: Initial experience from the Gastrocentro - Unicamp

OBJECTIVE: Endoscopic submucosal dissection is a technique developed in Japan for en bloc resection with a lower rate of recurrence. It is considered technically difficult and performed only in specialized centers. This study sought to report the initial experience from the Gastrocentro - Campinas State University for the treatment of gastric and colorectal lesions by endoscopic submucosal dissection. MATERIALS AND METHODS: The guidelines of the Japanese Association of Gastric Cancer were used as evaluative criteria. For colorectal lesions, the recommended standards proposed by Uraoka et al. and Saito et al. were employed. The practicability of the method, the development of complications and histological analysis of the specimens were evaluated. RESULTS: Sixteen patients underwent endoscopic submucosal dissection from June 2010 to April 2011; nine patients were treated for gastric lesions, and seven were treated for colorectal lesions. The average diameter of the gastric lesions was 28.6 mm, and the duration of resection was 103 min without complications. All lesions presented lesion-free margins. Of the seven colorectal tumors, four were located in the rectum and three were located in the colon. The average size was 26 mm, and the average procedure time was 163 min. Two complications occurred during the rectal resection procedures: perforation, which was treated with an endoscopic clip, and controlled bleeding. One of the lesions presented a compromised lateral margin without relapse after 90 days. Depth margins were all free of lesions. CONCLUSION: Endoscopic submucosal dissection at our institution achieved high success rates, with few complications in preliminary procedures. The procedure also made appropriate lesion staging possible.

Disección endoscópica de la submucosa (DES) para el cáncer gástrico temprano: Estado del arte / Endoscopic submucosal dissection (ESD) for early gastric cancer: state of the art

El tratamiento del cáncer gástrico temprano ha experimentado cambios revolucionarios en las décadas desde la aparición del tratamiento endoscópico. En la actualidad, la mayoría de estas lesiones tempranas son tratados con disección endoscópica de la submucosa (ESD). Debido a la excelente programa de detección implementado en Japón casi la mitad de todos los casos de cáncer gástrico no se tratan con la EDS. El objetivo de este artículo de revisión es facilitar el uso de esta técnica por endoscopistas latinoamericanos y así beneficiar a nuestros pacientes. Para ello ofrecemos una descripción detallada de la EDS, mostrar el estado actual de las indicaciones de esta técnica, y explicar las limitaciones de esta técnica. Este estudio fue realizado por endoscopistas entrenados en la EDS en Japón y bajo la supervisión de un endoscopista experto japonés (TT) que se habían realizado más de 4.000 con disección endoscópica de la submucosa a partir de principios de 2012.

The treatment of early gastric cancer has undergone revolutionary changes in the decades since the advent of endoscopic management. Currently, most of these early lesions are treated with endoscopic submucosal dissection (ESD). Due to the excellent screening program implemented in Japan almost half of all cases of gastric cancer there are treated with ESD. The aim of this review article is to facilitate the use of this technique by Latin American endoscopists and thus benefit our patients. To this end we provide a detailed description of ESD, show the current state of indications for this technique, and explain the limitations of this technique. This study was conducted by endoscopists trained in ESD in Japan and supervised by an expert Japanese endoscopist (TT) who had performed more than 4,000 with endoscopic submucosal dissections as of the beginning of 2012.

To be or not to be: disección endoscópica submucosa o resección endoscópica de la mucosa en el tratamiento de las neoplasias gastrointestinales / To be or not to be: endoscopic sub-mucosal dissection or endoscopic mucosal resection for treatment of gastrointestinal neoplasia

Endoscopic treatment of early gastrointestinal neoplasias has become the standard treatment in Japan and other Asia-Pacific countries, while it is still a developing technology in the West. The advent of endoscopic mucosal resection and endoscopic sub-mucosal dissection in the last decade has allowed early treatment of malignancies in a manner that preserves the organ, avoiding major surgery with less morbidity and mortality, and overall survival rates compared to standard surgery. In Japan and other Asia-Pacific countries, submucosal dissection has shifted over endoscopic mucosal resection as the technique of choice in the recent years, because of the possibility of treating deeper and larger lesions, with higher rates of bloc and curative resections, and lower recurrence rates, but with a higher rate of complications and a longer learning curve.

El tratamiento endoscópico de las neoplasias gastrointestinales precoces se ha convertido en el estándar de tratamiento en Japón y otros países del Asia-Pacífico, siendo aún una técnica en desarrollo en occidente. La aparición de la resección endoscópica de la mucosa y la disección endoscópica submucosa en la última década, ha permitido tratar las neoplasias precoces, logrando preservar el órgano, y evitando así una cirugía mayor, con menor morbi-mortalidad y cifras de sobrevida comparables con el tratamiento quirúrgico convencional. En Japón y otros países del Asia-Pacífico, la disección sub-mucosa ha desplazado en los últimos años a la resección endoscópica de la mucosa como técnica de elección, debido a la posibilidad de resecar lesiones más profundas y de mayor tamaño, con mayor tasa de resección en bloque y curativa, y menor recidiva. Sin embargo, con una mayor tasa de complicaciones y una curva de aprendizaje más larga.

Factores morfológicos asociados al pronóstico de pacientes operados por cáncer gástrico incipiente / Pathological features associated with survival in early gastric cancer

Background: Early gastric cancer corresponds to those tumors that only involve mucosa and submuco-sa. It is associated with a high survival rate. Aim: To determine pathological factors associated with survival in early gastric cancer. Material and Methods: Analysis of pathological records of 106 patients, with a median age of 63 years (60 percent> males), subjected to a gastrectomy for early gastric cancer. Follow up was performed according to data in the clinical records and death certificates obtained at the Chilean National Death Registry. Results: Five years global survival of patients was 91 percento. Lymph node involvement was more common among tumors bigger than 35 mm, with a low degree of differentiation and among those tumors classified as diffuse according to Lauren. Survival was significantly lower for bigger tumors, those with of a low degree of differentiation, diffuse tumors according to Lauren and those with lymph node involvement. Conclusions: Early gastric cancer has a high five years survival. Bigger tumors, those with a low degree of differentiation and those with lymph node involvement are associated with lower survival rates.

Introducción: El cáncer gástrico incipiente (CGI) es aquel que compromete la mucosa o submucosa gástrica independientemente del compromiso ganglionar linfático, estimándose su prevalencia en Chile inferior al 20 por cientoo. El objetivo de este estudio es determinar prevalencia de CGI y asociación de variables biode-mográficas y morfológicas con la supervivencia (SV) de pacientes resecados por CGI. Material y Método: Estudio de cohorte retrospectiva. Se estudiaron variables biodemográficas y morfológicas de 106 pacientes resecados por CGI entre 1986-2007. Se aplicó estadística descriptiva y analítica; confección de curvas de SV, y finalmente se aplicaron modelos de regresión logística para realizar ajuste, calcular odds ratio y sus respectivos intervalos de confianza de 95 por ciento. Resultados: 15 por ciento correspondió a CGI. La mediana de edad fue 63 años y el 60 por ciento correspondió a género masculino con una SV global a 5 años de 91 por ciento. Se observaron diferencias estadísticas significativas entre tumores mucosos y submucosos en cuanto a la localización tumoral y compromiso linfonodal junto con presentarse el compromiso nodal más frecuentemente en tumores > 35mm poco diferenciados y difusos de Lauren. El análisis multivariado identificó como factores asociados a la SV: tamaño tumoral, grado de diferenciación histológica en su variedad poco diferenciado, tipo difuso de Lauren y compromiso ganglionar linfático. Conclusiones: Se verificó una prevalencia de CGI de 15 por ciento, los que resecados presentan SV de 91 por ciento a 5 años. El compromiso linfonodal es un factor asociado a la SV; y además, se relaciona con tamaño tumoral, tipo histológico según Lauren, grado de diferenciación histológico y nivel de infiltración.