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Dive into the research topics where Almir Galvão Vieira Bitencourt is active.

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Featured researches published by Almir Galvão Vieira Bitencourt.


Radiologia Brasileira | 2014

Correlação entre resultado do PET/CT e achados histológicos e imuno-histoquímicos em carcinomas mamários

Almir Galvão Vieira Bitencourt; Eduardo Nóbrega Pereira Lima; Rubens Chojniak; Elvira Ferreira Marques; Juliana Alves de Souza; Luciana Graziano; Wesley Pereira Andrade; Cynthia Aparecida Bueno de Toledo Osório

Objective To correlate the results of 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) performed with a specific protocol for assessment of breasts with histological/immunohistochemical findings in breast carcinoma patients. Materials and Methods Cross-sectional study with prospective data collection, where patients with biopsy-confirmed breast carcinomas were studied. The patients underwent PET/CT examination in prone position, with a specific protocol for assessment of breasts. PET/CT findings were compared with histological and immunohistochemical data. Results The authors identified 59 malignant breast lesions in 50 patients. The maximum diameter of the lesions ranged from 6 to 80 mm (mean: 32.2 mm). Invasive ductal carcinoma was the most common histological type (n = 47; 79.7%). At PET/CT, 53 (89.8%) of the lesions demonstrated anomalous concentrations of 18F-FDG, with maximum SUV ranging from 0.8 to 23.1 (mean: 5.5). A statistically significant association was observed between higher values of maximum SUV and histological type, histological grade, molecular subtype, tumor diameter, mitotic index and Ki-67 expression. Conclusion PET/CT performed with specific protocol for assessment of breasts has demonstrated good sensitivity and was associated with relevant histological/immunohistochemical factors related to aggressiveness and prognosis of breast carcinomas.Objective To correlate the results of 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) performed with a specific protocol for assessment of breasts with histological/immunohistochemical findings in breast carcinoma patients. Materials and Methods Cross-sectional study with prospective data collection, where patients with biopsy-confirmed breast carcinomas were studied. The patients underwent PET/CT examination in prone position, with a specific protocol for assessment of breasts. PET/CT findings were compared with histological and immunohistochemical data. Results The authors identified 59 malignant breast lesions in 50 patients. The maximum diameter of the lesions ranged from 6 to 80 mm (mean: 32.2 mm). Invasive ductal carcinoma was the most common histological type (n = 47; 79.7%). At PET/CT, 53 (89.8%) of the lesions demonstrated anomalous concentrations of 18F-FDG, with maximum SUV ranging from 0.8 to 23.1 (mean: 5.5). A statistically significant association was observed between higher values of maximum SUV and histological type, histological grade, molecular subtype, tumor diameter, mitotic index and Ki-67 expression. Conclusion PET/CT performed with specific protocol for assessment of breasts has demonstrated good sensitivity and was associated with relevant histological/immunohistochemical factors related to aggressiveness and prognosis of breast carcinomas.


Clinics | 2009

New applications of radioguided surgery in oncology

Almir Galvão Vieira Bitencourt; Eduardo Nóbrega Pereira Lima; Paula Nicole Vieira Pinto; Eduardo Bruno Lobato Martins; Rubens Chojniak

OBJECTIVE: To report oncological cases (excluding those related to breast cancer) for which radioguided surgery has been used in combination with the Radioguided Occult Lesion Localization technique. INTRODUCTION: Radioguided surgery enables a surgeon to identify lesions or tissues that have been preoperatively marked with radioactive substances. The Radioguided Occult Lesion Localization technique has been widely used to identify the sentinel lymph node and occult lesions in patients with breast cancer. However, few studies have reported the use of this technique for non-breast cancer pathologies. METHODOLOGY: In all cases, injection of Technecium-99m sulfur colloid was performed, directly inside or near by the suspicious lesion, guided by ultrasound or computed tomography, up to 36 hours prior to the surgical procedure. Intraoperative lesion detection was carried out using a gamma-probe. RESULTS: We report five oncology cases in which preoperative markings of the lesions were carried out using the Radioguided Occult Lesion Localization technique. The patients presented with the following: recurrence of renal cell carcinoma, cervical recurrence of papillary carcinoma of the thyroid, recurrence of retroperitoneal sarcoma, lesions of the popliteal fossa, and recurrence of rhabdomyosarcoma of a thigh. In each case, the lesions that were marked preoperatively were ultimately successfully excised. CONCLUSIONS: Radioguided surgery has proven to be a safe and effective alternative for the management of oncology patients. The Radioguided Occult Lesion Localization technique can be useful in selected cases where suspect lesions may be difficult to identify intraoperatively, due to their dimensions or anatomical location. The procedure allows for more conservative excisions and reduces the surgery-related morbidity.


Ejso | 2013

Can FDG-PET/CT predict early response to neoadjuvant chemotherapy in breast cancer?

Wesley Pereira Andrade; Eduardo Nóbrega Pereira Lima; Cyntia Osório; M. Do Socorro MacIel; Glauco Baiocchi; Almir Galvão Vieira Bitencourt; Marcello Ferretti Fanelli; Aline Santos Damascena; Fernando Augusto Soares

PURPOSE Neoadjuvant chemotherapy (NAC) in breast cancer is currently used not only for locally advanced tumors, but also for large operable tumors when breast preservation is considered. It also provides the opportunity to evaluate chemotherapy tumor response. Our aim was to correlate the relative change in the standardized uptake value (SUV) of (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET/CT) with pathologic response after NAC. METHODS We prospectively evaluated 40 patients with invasive ductal breast carcinomas from February 2010 to December 2011. FDG-PET/CT was performed at baseline and after the second cycle of NAC. All patients underwent surgery after NAC. Pathologic response was evaluated according to Residual Cancer Burden (RCB) index. RESULTS The mean age was 41.9 years. Median primary tumor size was 6 cm. Pathologic complete response (pCR) was obtained in 12 (30%) patients. The tumor baseline mean maximum SUV (SUV(max)), and after second cycle were: 8.97 (sd.4.3) and 4.07 (sd.3.2), respectively. The relative change (ΔSUV) after the second course of NAC was significantly higher for patients with pCR (-81.58%) when compared to the non-pCR patients (-40.18%) (p = 0.001). The optimal ΔSUV threshold that discriminates between pCR and non-pCR was -71.8% (83.3% sensitivity; 78.5% specificity). Moreover, the optimal ΔSUV threshold to discriminate between NAC responders and non-responders was -59.1% (68% sensitivity; 75.0% specificity). CONCLUSIONS Our data suggest that the FDG-PET/CT ΔSUV after the second course of NAC can predict pathological response in ductal breast carcinomas, and potentially identify a subgroup of non-responding patients for whom ineffective chemotherapy should be avoided. SYNOPSIS Breast cancer is the most frequently diagnosed cancer in women. The indications for neoadjuvant chemotherapy are increasing. Early information on chemotherapy response is crucial and methods that predict the therapeutic effectiveness might avoid potentially ineffective chemotherapies in non-responding patients.


British Journal of Radiology | 2012

Technical note: CT-guided paravertebral adrenal biopsy using hydrodissection—a safe and technically easy approach

Chiang J. Tyng; Almir Galvão Vieira Bitencourt; Eduardo Bruno Lobato Martins; Paula Nicole Vieira Pinto; Rubens Chojniak

The adrenal glands are an important site of both primary and secondary disease processes. Image-guided percutaneous biopsy of the adrenal gland is an accurate and safe alternative to surgical biopsy. This procedure is most often performed in patients with a suspicion of metastatic disease where an accurate pathological diagnosis plays an important role in disease staging and defining therapy. There are many different approaches to performing adrenal biopsy under CT guidance such as anterior transhepatic/transpancreatic, lateral transhepatic/transplenic or posterior transpulmonary/transpleural/paravertebral. We describe a technique in which the adrenal gland was biopsied using a CT-guided percutaneous paravertebral approach with the use of a hydrodissection manoeuver. 13 CT-guided adrenal gland percutaneous biopsies using this technique were performed at our institution between April 2009 and July 2010. All biopsies yielded sufficient material for pathological analysis and there were no complications reported after the procedure. Saline injection can expand the posterior paravertebral space and facilitate a posterior extrapleural approach with high accuracy and low complication rates, and we believe that this may be the best approach for adrenal gland biopsy.


Radiologia Brasileira | 2014

Biópsia percutânea de lesões ósseas guiada por tomografia computadorizada: taxas de definição diagnóstica e complicações

Macello Jose Sampaio Maciel; Chiang Jeng Tyng; Paula Nicole Vieira Pinto Barbosa; Almir Galvão Vieira Bitencourt; João Paulo Kawaoka Matushita Junior; Charles Edouard Zurstrassen; Wu Tu Chung; Rubens Chojniak

Objective: To determine the rates of diagnostic success and complications of computed tomography (CT)-guided percutaneous biopsy of bone lesions suspected for malignancy. Materials and Methods: Retrospective study including 186 cases of CT-guided percutaneous biopsies of bone lesions in the period from January, 2010 to December, 2012. All the specimens were obtained with 8-10 gauge needles. The following data were collected: demographics, previous history of malignancy, data related to the lesion, to the procedure, and to histological results. Results: Most patients were women (57%), and the mean age was 53.0 ± 16.4 years. In 139 cases (74.6%), there was diagnostic suspicion of metastasis and the most common primary tumors were breast (32.1%) and prostate (11.8%). The bones most commonly involved were spine (36.0%), hip (32.8%) and long bones (18.3%). Complications occurred in only three cases (1.6%) including bone fracture, paresthesia with functional impairment, and needle breakage requiring surgical removal. The specimens collected from 183 lesions (98.4%) were considered appropriate for diagnosis. Malignant results were more frequently found in patients who had a suspected secondary lesion and history of known malignancy (p < 0.001), and in patients who underwent PET/CT-guided procedures (p = 0.011). Conclusion: CT-guided percutaneous biopsy is a safe and effective procedure for the diagnosis of suspicious bone lesions.Objective To determine the rates of diagnostic success and complications of computed tomography (CT)-guided percutaneous biopsy of bone lesions suspected for malignancy. Materials and Methods Retrospective study including 186 cases of CT-guided percutaneous biopsies of bone lesions in the period from January, 2010 to December, 2012. All the specimens were obtained with 8-10 gauge needles. The following data were collected: demographics, previous history of malignancy, data related to the lesion, to the procedure, and to histological results. Results Most patients were women (57%), and the mean age was 53.0 ± 16.4 years. In 139 cases (74.6%), there was diagnostic suspicion of metastasis and the most common primary tumors were breast (32.1%) and prostate (11.8%). The bones most commonly involved were spine (36.0%), hip (32.8%) and long bones (18.3%). Complications occurred in only three cases (1.6%) including bone fracture, paresthesia with functional impairment, and needle breakage requiring surgical removal. The specimens collected from 183 lesions (98.4%) were considered appropriate for diagnosis. Malignant results were more frequently found in patients who had a suspected secondary lesion and history of known malignancy (p < 0.001), and in patients who underwent PET/CT-guided procedures (p = 0.011). Conclusion CT-guided percutaneous biopsy is a safe and effective procedure for the diagnosis of suspicious bone lesions.


Radiologia Brasileira | 2012

Biópsia percutânea por agulha grossa de tumores de partes moles guiada por tomografia computadorizada: Resultados e correlação com análise da peça cirúrgica

Rubens Chojniak; Henrique Ramos Grigio; Almir Galvão Vieira Bitencourt; Paula Nicole Vieira Pinto; Chiang Jeng Tyng; Isabela Werneck da Cunha; Samuel Aguiar Junior; Ademar Lopes

OBJETIVO: Avaliar a eficacia da biopsia percutânea por agulha grossa (BPAG) de tumores de partes moles guiada por tomografia computadorizada (TC), em relacao ao sucesso na obtencao de amostra para analise, e comparar o diagnostico da BPAG com o resultado anatomopatologico da peca cirurgica, quando disponivel. MATERIAIS E METODOS: Foram revisados os prontuarios e laudos diagnosticos de 262 pacientes com tumores de partes moles submetidos a BPAG guiada por TC em um centro de referencia oncologico entre 2003 e 2009. RESULTADOS: Das 262 biopsias realizadas, foi possivel a obtencao de amostra adequada em 215 (82,1%). Os tumores mais prevalentes foram os sarcomas (38,6%), carcinomas metastaticos (28,8%), tumores mesenquimais benignos (20,5%) e linfomas (9,3%). Foi possivel realizar graduacao histologica em 92,8% dos pacientes com sarcoma, sendo a maioria (77,9%) classificada como alto grau. Do total de pacientes, 116 (44,3%) realizaram cirurgia para exerese e confirmacao diagnostica. A BPAG mostrou acuracia de 94,6% na identificacao de sarcomas, com sensibilidade de 96,4% e especificidade de 89,5%. A graduacao histologica teve concordância significativa entre a BPAG e a peca cirurgica (p < 0,001; kappa = 0,75). CONCLUSAO: A BPAG guiada por TC demonstrou elevada acuracia diagnostica na avaliacao de tumores de partes moles e na graduacao histologica dos sarcomas, permitindo um adequado planejamento terapeutico.


Radiation Oncology | 2009

Conformal radiotherapy for lung cancer: interobservers' variability in the definition of gross tumor volume between radiologists and radiotherapists

Chiang Jeng Tyng; Rubens Chojniak; Paula Nicole Vieira Pinto; Marcelle Alves Borba; Almir Galvão Vieira Bitencourt; Ricardo César Fogaroli; Douglas Guedes de Castro; Paulo Eduardo Ribeiro dos Santos Novaes

BackgroundConformal external radiotherapy aims to improve tumor control by boosting tumor dose, reducing morbidity and sparing healthy tissues. To meet this objective careful visualization of the tumor and adjacent areas is required. However, one of the major issues to be solved in this context is the volumetric definition of the targets. This study proposes to compare the gross volume of lung tumors as delineated by specialized radiologists and radiotherapists of a cancer center.MethodsChest CT scans of a total of 23 patients all with non-small cell lung cancer, not submitted to surgery, eligible and referred to conformal radiotherapy on the Hospital A. C. Camargo (São Paulo, Brazil), during the year 2004 were analyzed. All cases were delineated by 2 radiologists and 2 radiotherapists. Only the gross tumor volume and the enlarged lymph nodes were delineated. As such, four gross tumor volumes were achieved for each one of the 23 patients.ResultsThere was a significant positive correlation between the 2 measurements (among the radiotherapists, radiologists and intra-class) and there was randomness in the distribution of data within the constructed confidence interval.ConclusionThere were no significant differences in the definition of gross tumor volume between radiologists and radiotherapists.


Clinics | 2009

Predictive success factors for ct-guided fine needle aspiration biopsy of pulmonary lesions

Marcos Duarte Guimarães; Rubens Chojniak; Jefferson Luiz Gross; Almir Galvão Vieira Bitencourt

OBJECTIVE: Computed tomography-guided percutaneous fine needle aspiration biopsy of lung lesions is a simple, safe and reproducible procedure. Currently, it is widely used to diagnose lung lesions. However, different factors can influence the success rates of this procedure. The purpose of this study was to determine the influence of radiological and procedural characteristics in predicting the success rates of computed tomography-guided fine needle aspiration biopsy of lung lesions. SUBJECTS AND METHODS: A retrospective study was developed and involved 340 patients who were submitted to a consecutive series of 362 computed tomography-guided fine needle aspiration biopsies of lung lesions, between July 1996 and June 2004, using 22-gauge needles (Chiba). Variables such as the radiological characteristics of the lesions, secondary pulmonary radiological findings, and procedural techniques were studied. RESULTS: For this study, 304 (84%) fine needle aspiration biopsies of lung lesions provided sufficient material for cytological evaluation. The variables that predicted sufficient material for cytological evaluation were lesions larger than 40 mm (p=0.02), lesions on the superior lung lobes (p=0.02), and suspicion of primary lung malignancy (p=0.03). From the multivariate analysis, the only predictive variable for success of the biopsies was localization on the superior lobes (p=0.01). CONCLUSIONS: Computed tomography-guided percutaneous fine needle aspiration biopsy of lung lesions showed greater rates of success in biopsies performed in patients with suspicion of primary lung malignancy, with lesions located in the superior lobes, and that have diameters equal to and larger than 40 mm.


World Journal of Gastroenterology | 2015

Computed tomography-guided percutaneous core needle biopsy in pancreatic tumor diagnosis

Chiang Jeng Tyng; Maria Fernanda Arruda Almeida; Paula Nicole Vieira Pinto Barbosa; Almir Galvão Vieira Bitencourt; José Augusto A G Berg; Macello Jose Sampaio Maciel; Felipe José Fernandez Coimbra; Luiz Henrique O Schiavon; Maria Dirlei Begnami; Marcos Duarte Guimarães; Charles Edouard Zurstrassen; Rubens Chojniak

AIM To evaluate the techniques, results, and complications related to computed tomography (CT)-guided percutaneous core needle biopsies of solid pancreatic lesions. METHODS CT-guided percutaneous biopsies of solid pancreatic lesions performed at a cancer reference center between January 2012 and September 2013 were retrospectively analyzed. Biopsy material was collected with a 16-20 G Tru-Core needle (10-15 cm; Angiotech, Vancouver, CA) using a coaxial system and automatic biopsy gun. When direct access to the lesion was not possible, indirect (transgastric or transhepatic) access or hydrodissection and/or pneumodissection maneuvers were used. Characteristics of the patients, lesions, procedures, and histologic results were recorded using a standardized form. RESULTS A total of 103 procedures included in the study were performed on patients with a mean age of 64.8 year (range: 39-94 year). The mean size of the pancreatic lesions was 45.5 mm (range: 15-195 mm). Most (75/103, 72.8%) procedures were performed via direct access, though hydrodissection and/or pneumodissection were used in 22.2% (23/103) of cases and indirect transhepatic or transgastric access was used in 4.8% (5/103) of cases. Histologic analysis was performed on all biopsies, and diagnoses were conclusive in 98.1% (101/103) of cases, confirming 3.9% (4/103) of tumors were benign and 94.2% (97/103) were malignant; results were atypical in 1.9% (2/103) of cases, requiring a repeat biopsy to diagnose a neuroendocrine tumor, and surgical resection to confirm a primary adenocarcinoma. Only mild/moderate complications were observed in 9/103 patients (8.7%), and they were more commonly associated with biopsies of lesions located in the head/uncinate process (n = 8), than of those located in the body/tail (n = 1) of the pancreas, but this difference was not significant. CONCLUSION CT-guided biopsy of a pancreatic lesion is a safe procedure with a high success rate, and is an excellent option for minimally invasive diagnosis.


Journal of Clinical Ultrasound | 2011

Comparison of three types of preparations for abdominal sonography.

Paula Nicole Vieira Pinto; Rubens Chojniak; Marcela P. Cohen; Liao S. Yu; Marcony Queiroz-Andrade; Almir Galvão Vieira Bitencourt

The purpose of this randomized, prospective study was to evaluate the effect of three preparation types on the abdominal sonographic examination quality and on patient acceptance.

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Marcos Duarte Guimarães

Universidade Federal do Vale do São Francisco

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Flávia Branco Cerqueira Serra Neves

Escola Bahiana de Medicina e Saúde Pública

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Edson Marchiori

Federal University of Rio de Janeiro

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Nedy Maria Branco Cerqueira Neves

Escola Bahiana de Medicina e Saúde Pública

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Camila Silva Bôaventura

Escola Bahiana de Medicina e Saúde Pública

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Bruno Hochhegger

Universidade Federal de Ciências da Saúde de Porto Alegre

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Bruno Lima Moreira

Federal University of São Paulo

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