Alex Dias de Oliveira
Research Subjects
Alex Dias de Oliveira has a total of 25 co-authors. Here are the top co-authors by number of shared publications:
Marcos Duarte Guimarães
Affiliation Imaging Department, A.C. Camargo Cancer Center, São Paulo, SP, Brazil
2 shared publicationsRubens Chojniak
Affiliation Imaging Department, A.C. Camargo Cancer Center, São Paulo, SP, Brazil
2 shared publicationsAna Claudia de Oliveira Fernandes
Hospital A.C. Camargo Cancer Center, Brazil
1 shared publication- Bruno Hochhegger
Department of Radiology, University of Florida, Gainesville, USA
1 shared publication Camila Pinto Brito de Figueiredo Guimarães
Affiliation Imaging Department, A.C. Camargo Cancer Center, São Paulo, SP, Brazil
1 shared publicationCecília Maria Lima da Costa
Affiliation Pediatric Department, A.C. Camargo Cancer Center, São Paulo, SP, Brazil
1 shared publication
Latest Publications
- Open Access
- 2 August 2021
- Published by Sociedade Brasileira de Pneumologia e Tisiologia in Jornal Brasileiro de Pneumologia
- Vol. 47 (4) , e20210025
Routine follow-up after surgical treatment of lung cancer: is chest CT useful?
Objective: To report the experience of a routine follow-up program based on medical visits and chest CT. Methods: This was a retrospective study involving patients followed after complete surgical resection of non-small cell lung cancer between April of 2007 and December of 2015. The follow-up program consisted of clinical examination and chest CT. Each follow-up visit was classified as a routine or non-routine consultation, and patients were considered symptomatic or asymptomatic. The outcomes of the follow-up program were no evidence of cancer, recurrence, or second primary lung cancer. Results: The sample comprised 148 patients. The median time of follow-up was 40.1 months, and 74.3% of the patients underwent fewer chest CTs than those recommended in our follow-up program. Recurrence and second primary lung cancer were found in 17.6% and 11.5% of the patients, respectively. Recurrence was diagnosed in a routine medical consultation in 69.2% of the cases, 57.7% of the patients being asymptomatic. Second primary lung cancer was diagnosed in a routine medical appointment in 94.1% of the cases, 88.2% of the patients being asymptomatic. Of the 53 patients who presented with abnormalities on chest CT, 41 (77.3%) were diagnosed with cancer. Conclusion: Most of the cases of recurrence, especially those of second primary lung cancer, were confirmed by chest CT in asymptomatic patients, indicating the importance of a strict follow-up program that includes chest CTs after surgical resection of lung cancer.
- 2 August 2021
- Published by Sociedade Brasileira de Pneumologia e Tisiologia in Jornal Brasileiro de Pneumologia
- Vol. 47 (4) , e20210025
Open AccessRoutine follow-up after surgical treatment of lung cancer: is chest CT useful?
Objective: To report the experience of a routine follow-up program based on medical visits and chest CT. Methods: This was a retrospective study involving patients followed after complete surgical resection of non-small cell lung cancer between April of 2007 and December of 2015. The follow-up program consisted of clinical examination and chest CT. Each follow-up visit was classified as a routine or non-routine consultation, and patients were considered symptomatic or asymptomatic. The outcomes of the follow-up program were no evidence of cancer, recurrence, or second primary lung cancer. Results: The sample comprised 148 patients. The median time of follow-up was 40.1 months, and 74.3% of the patients underwent fewer chest CTs than those recommended in our follow-up program. Recurrence and second primary lung cancer were found in 17.6% and 11.5% of the patients, respectively. Recurrence was diagnosed in a routine medical consultation in 69.2% of the cases, 57.7% of the patients being asymptomatic. Second primary lung cancer was diagnosed in a routine medical appointment in 94.1% of the cases, 88.2% of the patients being asymptomatic. Of the 53 patients who presented with abnormalities on chest CT, 41 (77.3%) were diagnosed with cancer. Conclusion: Most of the cases of recurrence, especially those of second primary lung cancer, were confirmed by chest CT in asymptomatic patients, indicating the importance of a strict follow-up program that includes chest CTs after surgical resection of lung cancer.
- Open Access
- 27 August 2020
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 15 (8) , e0238166
Evaluation of whole-body MRI with diffusion-weighted sequences in the staging of pediatric cancer patients
The purpose of this study was to determine whether whole-body MRI (WBMRI) with diffusion-weighted sequences, which is free of ionizing radiation, can perform as well as traditional methods when used alone for staging or follow-up of pediatric cancer patients. After obtaining approval from our institutional research ethics committee and appropriate informed consent, we performed 34 examinations in 32 pediatric patients. The examinations were anonymized and analyzed by two radiologists with at least 10 years’ experience. The sensitivity and specificity findings, respectively, were as follows: 100% and 100% for primary tumor; 100% and 86% for bone metastasis; 33% and 100% for lung metastasis; 85% and 100% for lymph node metastasis; and 100% and 62% for global investigation of primary or secondary neoplasias. We observed excellent interobserver agreement for WBMRI and excellent agreement with standard staging examination results. Our results suggest that pediatric patients can be safely imaged with WBMRI, although not as the only tool but in association with low-dose chest CT (for subcentimeter pulmonary nodules). However, additional exams with ionizing radiation may be necessary for patients who tested positive to correctly quantify and locate the lesions.
- 27 August 2020
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 15 (8) , e0238166
Open AccessEvaluation of whole-body MRI with diffusion-weighted sequences in the staging of pediatric cancer patients
The purpose of this study was to determine whether whole-body MRI (WBMRI) with diffusion-weighted sequences, which is free of ionizing radiation, can perform as well as traditional methods when used alone for staging or follow-up of pediatric cancer patients. After obtaining approval from our institutional research ethics committee and appropriate informed consent, we performed 34 examinations in 32 pediatric patients. The examinations were anonymized and analyzed by two radiologists with at least 10 years’ experience. The sensitivity and specificity findings, respectively, were as follows: 100% and 100% for primary tumor; 100% and 86% for bone metastasis; 33% and 100% for lung metastasis; 85% and 100% for lymph node metastasis; and 100% and 62% for global investigation of primary or secondary neoplasias. We observed excellent interobserver agreement for WBMRI and excellent agreement with standard staging examination results. Our results suggest that pediatric patients can be safely imaged with WBMRI, although not as the only tool but in association with low-dose chest CT (for subcentimeter pulmonary nodules). However, additional exams with ionizing radiation may be necessary for patients who tested positive to correctly quantify and locate the lesions.
- Open Access
- 1 February 2018
- Published by FapUNIFESP (SciELO) in Revista da Associação Médica Brasileira
- Vol. 64 (2) , 195-199
Pseudomyxoma peritonei in a pediatric patient: A case report and literature review
Summary Introduction: Pseudomyxoma peritonei (PMP) is a rare clinical condition, with an incidence of 1-2 cases per million, characterized by the dissemination of mucinous implants on the peritoneal surface and progressive gelatinous ascites. Although it usually presents an indolent behavior, its non-specific clinical presentation contributes to many cases remaining undiagnosed until a laparotomy is performed. With late diagnosis, performed after a long period of clinical deterioration and disease progression, it is common to find complications such as the formation of intestinal fistulas and obstruction. Method: Review of the medical record and search for references in the Medline, Lilacs, SciELO and MD Consult databases. Results: There are rare case reports found in the literature demonstrating atypical PMP presentations. Our report is that of a 17-year-old adolescent with a sporadic tumor diagnosed in a primary site in the transverse colon, contrary to data commonly found in the literature that mention a more frequent occurrence in women in the fifth decade of life and with a primary site in the ovary and appendix. The development of mucinous adenocarcinoma is rare in the pediatric population, and topography in the transverse colon and non-familial sporadic pattern are unusual. Conclusion: The case reported not only raises awareness about the atypical presentations of the disease, but also emphasizes the use of imaging examinations for diagnosis, which has an important impact on prognosis and survival if performed timely.
- 1 February 2018
- Published by FapUNIFESP (SciELO) in Revista da Associação Médica Brasileira
- Vol. 64 (2) , 195-199
Open AccessPseudomyxoma peritonei in a pediatric patient: A case report and literature review
Summary Introduction: Pseudomyxoma peritonei (PMP) is a rare clinical condition, with an incidence of 1-2 cases per million, characterized by the dissemination of mucinous implants on the peritoneal surface and progressive gelatinous ascites. Although it usually presents an indolent behavior, its non-specific clinical presentation contributes to many cases remaining undiagnosed until a laparotomy is performed. With late diagnosis, performed after a long period of clinical deterioration and disease progression, it is common to find complications such as the formation of intestinal fistulas and obstruction. Method: Review of the medical record and search for references in the Medline, Lilacs, SciELO and MD Consult databases. Results: There are rare case reports found in the literature demonstrating atypical PMP presentations. Our report is that of a 17-year-old adolescent with a sporadic tumor diagnosed in a primary site in the transverse colon, contrary to data commonly found in the literature that mention a more frequent occurrence in women in the fifth decade of life and with a primary site in the ovary and appendix. The development of mucinous adenocarcinoma is rare in the pediatric population, and topography in the transverse colon and non-familial sporadic pattern are unusual. Conclusion: The case reported not only raises awareness about the atypical presentations of the disease, but also emphasizes the use of imaging examinations for diagnosis, which has an important impact on prognosis and survival if performed timely.
- Open Access
- 10 February 2017
- Published by Springer Nature in Cancer Imaging
- Vol. 17 (1) , 6
Whole-body MRI in pediatric patients with cancer
Cancer is the leading cause of natural death in the pediatric populations of developed countries, yet cure rates are greater than 70% when a cancer is diagnosed in its early stages. Recent advances in magnetic resonance imaging methods have markedly improved diagnostic and therapeutic approaches, while avoiding the risks of ionizing radiation that are associated with most conventional radiological methods, such as computed tomography and positron emission tomography/computed tomography. The advent of whole-body magnetic resonance imaging in association with the development of metabolic- and function-based techniques has led to the use of whole-body magnetic resonance imaging for the screening, diagnosis, staging, response assessment, and post-therapeutic follow-up of children with solid sporadic tumours or those with related genetic syndromes. Here, the advantages, techniques, indications, and limitations of whole-body magnetic resonance imaging in the management of pediatric oncology patients are presented.
- 10 February 2017
- Published by Springer Nature in Cancer Imaging
- Vol. 17 (1) , 6
Open AccessWhole-body MRI in pediatric patients with cancer
Cancer is the leading cause of natural death in the pediatric populations of developed countries, yet cure rates are greater than 70% when a cancer is diagnosed in its early stages. Recent advances in magnetic resonance imaging methods have markedly improved diagnostic and therapeutic approaches, while avoiding the risks of ionizing radiation that are associated with most conventional radiological methods, such as computed tomography and positron emission tomography/computed tomography. The advent of whole-body magnetic resonance imaging in association with the development of metabolic- and function-based techniques has led to the use of whole-body magnetic resonance imaging for the screening, diagnosis, staging, response assessment, and post-therapeutic follow-up of children with solid sporadic tumours or those with related genetic syndromes. Here, the advantages, techniques, indications, and limitations of whole-body magnetic resonance imaging in the management of pediatric oncology patients are presented.