Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where André Roncon Dias is active.

Publication


Featured researches published by André Roncon Dias.


Techniques in Coloproctology | 2009

Transanal endoscopic microsurgery: indications, results and controversies

André Roncon Dias; Caio Sergio Rizkallah Nahas; Carlos Frederico Sparapan Marques; Sergio Carlos Nahas; Ivan Cecconello

Transanal endoscopic microsurgery (TEM) was introduced in 1983 as a minimally invasive technique allowing the resection of adenomas and early rectal carcinomas unsuitable for local or colonoscopic excision which would otherwise require major surgery. After 25 years, there is still much debate about the procedure. This article presents the TEM technique, indications, results and complications, focusing on its role in rectal cancer. The controversial points addressed include long-term results, TEM in high-risk T1 lesions, TEM associated with combined modality therapy (CMT) for invasive rectal cancer and salvage therapy after TEM. The future perspectives for TEM are promising and its association with CMT will probably expand the select group of patients who will benefit from the procedure.


European Journal of Gastroenterology & Hepatology | 2013

Surgical management of gallbladder disease in the very elderly: are we operating them at the right time?

Renato Micelli Lupinacci; Luis R. Nadal; Ronaldo E. Rego; André Roncon Dias; Rafael S. Marcari; Renato Arioni Lupinacci; José Francisco de Mattos Farah

Background As life expectancy rises worldwide and the prevalence of gallstones increases with age, the number of very elderly patients requiring treatment for gallstone diseases is increasing. The aim of this study was to compare the results of cholecystectomy in patients 80 years or older according to different clinical presentations. Methods This is a retrospective study of 81 patients 80 years or older. Indications for surgery were stratified into three groups: outpatients (symptomatic chronic cholecystitis), inpatients (complicated gallstone diseases), and urgent patients (acute cholecystitis). Data analysis included age, sex, the American Society of Anesthesiologists score, indication for surgery, length of hospital stay, morbidity, and mortality. Results The mean age of the patients was 83.9 (range 80–94 years); there were 34 (42%) men. Thirty patients were operated on for acute cholecystitis. Patients in the urgency group significantly required the ICU more often, required a longer hospital stay, and had more complications, with 32% mortality. No differences were found between inpatients and outpatients, with both groups presenting low morbidity, no mortality, and the same postoperative length of stay. Conclusion More than 80% of the patients were operated on because of complicated gallstone disease. Although the outcomes of patients undergoing semielective cholecystectomy were similar to those of patients treated as outpatients, patients operated with acute cholecystitis presented extremely high morbidity and mortality rates. Thus, we can only recommend that early elective cholecystectomy be performed in elderly patients as soon as they are found to have symptomatic gallstones. Also, further trials are required to elucidate the optimal management of acute cholecystitis in elderly patients.


World Journal of Surgical Oncology | 2012

Isolated splenic metastasis from lung squamous cell carcinoma

André Roncon Dias; Rodrigo Ambar Pinto; Juliana N Ravanini; Renato Micelli Lupinacci; Ivan Cecconello; Ulysses Ribeiro

Isolated splenic metastasis from lung cancer is a very rare occurrence with only a few reports available. Here, we report the case of a 82-year-old male who underwent a bilobectomy for a lung squamous cell carcinoma and 16 months later developed an isolated splenic metastasis. Additionally, previous reports are reviewed and discussed.


ABCD. Arquivos Brasileiros de Cirurgia Digestiva (São Paulo) | 2010

Transanal endoscopic microsurgery (TEM): a minimally invasive procedure for treatment of selected rectal neoplasms

Sergio Carlos Nahas; Caio Sergio Rizkallah Nahas; Carlos Frederico Sparapan Marques; André Roncon Dias; Wilson Modesto Pollara; Ivan Cecconello

A microcirurgia endoscopica transanal (TEM) e procedimento alternativo minimamente invasivo ao tratamento cirurgico radical para excisao de tumores benignos e malignos do reto. Ela oferece possibilidade operatoria aos procedimentos cirurgicos convencionais (resseccao anterior baixa ou amputacoes abdominoperineais), as quais acarretam alta morbimortalidade. Baseada na revisao da literatura e na experiencia propria dos autores, esta revisao tem por objetivo apresentar o metodo e as indicacoes para a TEM.


Histopathology | 2015

Carnoy's solution is an adequate tissue fixative for routine surgical pathology, preserving cell morphology and molecular integrity.

Marina Alessandra Pereira; André Roncon Dias; Sheila Friedrich Faraj; Cinthya dos Santos Cirqueira; Michele Tatiana Pereira Tomitao; Sergio Carlos Nahas; Ulysses Ribeiro; Evandro Sobroza de Mello

To compare Carnoys solution (CS) and 10% neutral buffered formalin solution (NBF) as tissue fixatives in colorectal cancer specimens.


Techniques in Coloproctology | 2010

Synchronous collision malignant melanoma and adenocarcinoma of the rectum

André Roncon Dias; Rodrigo Ambar Pinto; E. Mory; I. C. Silva; S. A. C. Siqueira; Sergio Carlos Nahas; Ivan Cecconello; Steven D. Wexner

Abstract“Collision tumors” consist of two independent but coexisting tumors. This uncommon situation might be easily mistaken for a composite tumor where one histogenetic event originates from two apparently distinct neoplasms. Colorectal collisions are particularly unusual; here, we report the exceedingly rare case of a 61-year-old man with malignant melanoma and adenocarcinoma colliding in the rectum. Collision tumors have an idiopathic pathophysiology and in fact “accidental meeting” is accepted by many authors. This article discusses the concepts about cancer development, which are overlooked by this hypothesis, another theory to explain that this rare occurrence involves microenvironment changes.


Clinics | 2010

Squamous cell carcinoma and neuroendocrine carcinoma colliding in the esophagus.

André Roncon Dias; Rubens Sallum; Nathalia Zalc; Bruno Ctenas; Ulysses Ribeiro; Ivan Cecconello

A collision tumor consists of two independent neoplasms growing in close proximity until they become juxtaposed, appearing as one lesion. This is a very rare situation with unclear physiopathology. Collision tumors should be distinguished from composite tumors, which consist of one neoplastic clone that diverges into two cell lineages. Collisions located in the esophagus are particularly uncommon.


Arquivos brasileiros de cirurgia digestiva : ABCD = Brazilian archives of digestive surgery | 2016

MINIMALLY INVASIVE SURGERY FOR GASTRIC CANCER: TIME TO CHANGE THE PARADIGM

Leandro Barchi; Carlos Eduardos Jacob; Cláudio Bresciani; Osmar Kenji Yagi; Donato Mucerino; Fábio Pinatel Lopasso; Marcelo Mester; Ulysses Ribeiro-Junior; André Roncon Dias; Marcus Fernando Kodama Pertille Ramos; Ivan Cecconello; Bruno Zilberstein

ABSTRACT Introduction: Minimally invasive surgery widely used to treat benign disorders of the digestive system, has become the focus of intense study in recent years in the field of surgical oncology. Since then, the experience with this kind of approach has grown, aiming to provide the same oncological outcomes and survival to conventional surgery. Regarding gastric cancer, surgery is still considered the only curative treatment, considering the extent of resection and lymphadenectomy performed. Conventional surgery remains the main modality performed worldwide. Notwithstanding, the role of the minimally invasive access is yet to be clarified. Objective: To evaluate and summarize the current status of minimally invasive resection of gastric cancer. Methods: A literature review was performed using Medline/PubMed, Cochrane Library and SciELO with the following headings: gastric cancer, minimally invasive surgery, robotic gastrectomy, laparoscopic gastrectomy, stomach cancer. The language used for the research was English. Results: 28 articles were considered, including randomized controlled trials, meta-analyzes, prospective and retrospective cohort studies. Conclusion: Minimally invasive gastrectomy may be considered as a technical option in the treatment of early gastric cancer. As for advanced cancer, recent studies have demonstrated the safety and feasibility of the laparoscopic approach. Robotic gastrectomy will probably improve outcomes obtained with laparoscopy. However, high cost is still a barrier to its use on a large scale.


Surgery Today | 2013

A modified supralevator pelvic exenteration for the treatment of locally advanced rectal cancer with vaginal and uterine invasion

André Roncon Dias; Sergio Carlos Nahas

Post-chemoradiation T4 rectal cancer remains a therapeutic challenge and an aggressive surgical approach is the only chance for a cure. Rectal lesions infiltrating the upper vaginal wall and uterine cervix are usually treated by low anterior resection with en bloc removal of the vagina and uterus. However, failure can occur when one is trying to access the anterior recto-vaginal plane below the tumor, especially in obese patients with a narrow pelvis. The remaining surgical alternatives are aggressive and debilitating. The objective of the study is to describe a modified supralevator pelvic exenteration for selected patients. A new surgical option is added to the armamentarium of the oncologic surgeon. The discussion focuses on the indications for this surgical technique and its advantages, such as the preservation of the anal sphincter and the vagina, thus allowing for fecal continence and sexual activity.


Journal of Gastrointestinal Surgery | 2018

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

Marina Alessandra Pereira; Marcus Fernando Kodama Pertille Ramos; André Roncon Dias; Sheila Friedrich Faraj; Osmar Kenji Yagi; Adriana V. Safatle-Ribeiro; Fauze Maluf-Filho; Bruno Zilberstein; Ivan Cecconello; Evandro Sobroza de Mello; Ulysses Ribeiro

BackgroundLymph 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.MethodsEGC 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.ResultsAmong 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.ConclusionsTumor 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.

Collaboration


Dive into the André Roncon Dias's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge