JOAO MANOEL MIRANDA MAGALHAES SANTOS
Índice h a partir de 2011
6
Projetos de Pesquisa
Unidades Organizacionais
LIM/65, Hospital das Clínicas, Faculdade de Medicina
14 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 14
- CT Imaging Assessment of Pancreatic Adenocarcinoma Resectability after Neoadjuvant Therapy: Current Status and Perspective on the Use of Radiomics(2023) KHASAWNEH, Hala; PRIA, Hanna Rafaela Ferreira Dalla; MIRANDA, Joao; NEVIN, Rachel; CHHABRA, Shalini; HAMDAN, Dina; CHAKRABORTY, Jayasree; CASTRIA, Tiago Biachi de; HORVAT, NatallyPancreatic adenocarcinoma (PDAC) is the most common pancreatic cancer and is associated with poor prognosis, a high mortality rate, and a substantial number of healthy life years lost. Surgical resection is the primary treatment option for patients with resectable disease; however, only 10-20% of all patients with PDAC are eligible for resection at the time of diagnosis. In this context, neoadjuvant therapy has the potential to increase the number of patients who are eligible for resection, thereby improving the overall survival rate. For patients who undergo neoadjuvant therapy, computed tomography (CT) remains the primary imaging tool for assessing treatment response. Nevertheless, the interpretation of imaging findings in this context remains challenging, given the similarity between viable tumor and treatment-related changes following neoadjuvant therapy. In this review, following an overview of the various treatment options for PDAC according to its resectability status, we will describe the key challenges regarding CT-based evaluation of PDAC treatment response following neoadjuvant therapy, as well as summarize the literature on CT-based evaluation of PDAC treatment response, including the use of radiomics. Finally, we will outline key recommendations for the management of PDAC after neoadjuvant therapy, taking into consideration CT-based findings.
- Eosinophilic Solid and Cystic Renal Cell Carcinoma: Imaging Features of a Novel Neoplasm(2018) FENELON, Sandro Santos; SANTOS, Joao Manoel Miranda Magalhaes; FARAJ, Sheila Friedrich; MATTEDI, Romulo Loss; TRPKOV, Kiril; NAHAS, William Carlos; GARCIA, Marcio Ricardo Taveira; VIANA, Publio Cesar CavalcanteEosinophilic solid and cystic renal cell carcinoma (ESC RCC) is a recently described entity with distinct clinical, pathologic, and molecular features. However, the radiological aspects of ESC RCC have not been characterized. In this report, we describe the imaging findings of 2 ESC RCCs. We found 2 distinct imaging patterns that varied depending on histopathologic features (solid or cystic predominance). In conclusion, it is important to know the imaging characteristics and pathologic correlation of this novel neoplasm to increase its recognition and to improve the decision-making process. (C) 2018 Elsevier Inc.
- Case 297: Mucinous Adenocarcinoma of the Prostate(2022) KANAS, Alexandre Fligelman; FENELON, Sandro Santos; SANTOS, Joao Manoel Miranda Magalhaes; COELHO, Rafael Ferreira; GUGLIELMETTI, Giuliano Betoni; NAHAS, William Carlos; VIANA, Publio Cesar Cavalcante
- MRI-based radiomic score increased mrTRG accuracy in predicting rectal cancer response to neoadjuvant therapy(2023) MIRANDA, Joao; HORVAT, Natally; ASSUNCAO JR., Antonildes N.; MACHADO, Felipe Augusto de M.; CHAKRABORTY, Jayasree; PANDINI, Rafael Vaz; SARAIVA, Samya; NAHAS, Caio Sergio Rizkallah; NAHAS, Sergio Carlos; NOMURA, Cesar HigaPurpose To develop a magnetic resonance imaging (MRI)-based radiomics score, i.e., ""rad-score,"" and to investigate the performance of rad-score alone and combined with mrTRG in predicting pathologic complete response (pCR) in patients with locally advanced rectal cancer following neoadjuvant chemoradiation therapy. Methods This retrospective study included consecutive patients with LARC who underwent neoadjuvant chemoradiotherapy followed by surgery from between July 2011 to November 2015. Volumes of interest of the entire tumor on baseline rectal MRI and of the tumor bed on restaging rectal MRI were manually segmented on T2-weighted images. The radiologist also provided the ymrTRG score on the restaging MRI. Radiomic score (rad-score) was calculated and optimal cut-off points for both mrTRG and rad-score to predict pCR were selected using Youden's J statistic. Results Of 180 patients (mean age = 63 years; 60% men), 33/180 (18%) achieved pCR. High rad-score (> - 1.49) yielded an area under the curve (AUC) of 0.758, comparable to ymrTRG 1-2 which yielded an AUC of 0.759. The combination of high rad-score and ymrTRG 1-2 yielded a significantly higher AUC of 0.836 compared with ymrTRG 1-2 and high rad-score alone (p < 0.001). A logistic regression model incorporating both high rad-score and mrTRG 1-2 was built to calculate adjusted odds ratios for pCR, which was 4.85 (p < 0.001). Conclusion Our study demonstrates that a rectal restaging MRI-based rad-score had comparable diagnostic performance to ymrTRG. Moreover, the combined rad-score and ymrTRG model yielded a significant better diagnostic performance for predicting pCR.
- State-of-the-art in radiomics of hepatocellular carcinoma: a review of basic principles, applications, and limitations(2020) SANTOS, Joao Manoel Miranda Magalhaes; OLIVEIRA, Brunna Clemente; ARAUJO-FILHO, Jose de Arimateia Batista; ASSUNCAO- JR., Antonildes N.; MACHADO, Felipe Augusto de M.; ROCHA, Camila Carlos Tavares; HORVAT, Joao Vicente; MENEZES, Marcos Roberto; HORVAT, NatallyRadiomics is a new field in medical imaging with the potential of changing medical practice. Radiomics is characterized by the extraction of several quantitative imaging features which are not visible to the naked eye from conventional imaging modalities, and its correlation with specific relevant clinical endpoints, such as pathology, therapeutic response, and survival. Several studies have evaluated the use of radiomics in patients with hepatocellular carcinoma (HCC) with encouraging results, particularly in the pretreatment prediction of tumor biological characteristics, risk of recurrence, and survival. In spite of this, there are limitations and challenges to be overcome before the implementation of radiomics into clinical routine. In this article, we will review the concepts of radiomics and their current potential applications in patients with HCC. It is important that the multidisciplinary team involved in the treatment of patients with HCC be aware of the basic principles, benefits, and limitations of radiomics in order to achieve a balanced interpretation of the results toward a personalized medicine.
- A primer on texture analysis in abdominal radiology(2022) HORVAT, Natally; MIRANDA, Joao; HOMSI, Maria El; PEOPLES, Jacob J.; LONG, Niamh M.; SIMPSON, Amber L.; DO, Richard K. G.The number of publications on texture analysis (TA), radiomics, and radiogenomics has been growing exponentially, with abdominal radiologists aiming to build new prognostic or predictive biomarkers for a wide range of clinical applications including the use of oncological imaging to advance the field of precision medicine. TA is specifically concerned with the study of the variation of pixel intensity values in radiological images. Radiologists aim to capture pixel variation in radiological images to deliver new insights into tumor biology that cannot be derived from visual inspection alone. TA remains an active area of investigation and requires further standardization prior to its clinical acceptance and applicability. This review is for radiologists interested in this rapidly evolving field, who are thinking of performing research or want to better interpret results in this arena. We will review the main concepts in TA, workflow processes, and existing challenges and steps to overcome them, as well as look at publications in body imaging with external validation.
- Rectal MRI radiomics for predicting pathological complete response: Where we are(2022) MIRANDA, Joao; TAN, Gary Xia Vern; FERNANDES, Maria Clara; YILDIRIM, Onur; SIMS, John A.; ARAUJO-FILHO, Jose De Arimateia Batista; MACHADO, Felipe Augusto de M.; ASSUNCAO-JR, Antonildes N.; NOMURA, Cesar Higa; HORVAT, NatallyRadiomics using rectal MRI radiomics has emerged as a promising approach in predicting pathological complete response. In this study, we present a typical pipeline of a radiomics analysis and review recent studies, exploring applications, development of radiomics methodologies and model construction in pCR prediction. Finally, we will offer our opinion about the future and discuss the next steps of rectal MRI radiomics for predicting pCR.
- Advances in MRI-Based Assessment of Rectal Cancer Post-Neoadjuvant Therapy: A Comprehensive Review(2024) MIRANDA, Joao; ANDRIEU, Pamela Causa; NINCEVIC, Josip; FARIAS, Lucas de Padua Gomes de; KHASAWNEH, Hala; ARITA, Yuki; STANIETZKY, Nir; FERNANDES, Maria Clara; CASTRIA, Tiago Biachi De; HORVAT, NatallyRectal cancer presents significant diagnostic and therapeutic challenges, with neoadjuvant therapy playing a pivotal role in improving resectability and patient outcomes. MRI serves as a critical tool in assessing treatment response. However, differentiating viable tumor tissue from therapy-induced changes on MRI remains a complex task. In this comprehensive review, we explore treatment options for rectal cancer based on resectability status, focusing on the role of MRI in guiding therapeutic decisions. We delve into the nuances of MRI-based evaluation of treatment response following neoadjuvant therapy, paying particular attention to emerging techniques like radiomics. Drawing from our insights based on the literature, we provide essential recommendations for post-neoadjuvant therapy management of rectal cancer, all within the context of MRI-based findings.
- Abdominal gastrointestinal imaging findings on computed tomography in patients with COVID-19 and correlation with clinical outcomes(2021) HORVAT, Natally; PINTO, Paulo Victor Alves; ARAUJO-FILHO, Jose De Arimateia Batista; SANTOS, Joao Manoel Miranda Magalhaes; DIAS, Adriano Basso; MIRANDA, Julia Azevedo; OLIVEIRA, Camila Vilela de; BARBOSA, Camila Silva; MORAIS, Thamara Carvalho; ASSUNCAO-JR, Antonildes N.; NOMURA, Cesar Higa; VIANA, Publio Cesar CavalcantePurpose: Pulmonary imaging finding of Coronavirus disease 2019 (COVID-19) has been widely described, but until now few studies have been published about abdominal radiological presentation. The aim of this study was to provide an overview of abdominal imaging findings in patients with COVID-19 in a multicenter study and correlate them with worse clinical outcomes. Materials and methods: This retrospective study included adult COVID-positive patients with abdominal CT performed from 4/1/2020 to 5/1/2020 from two institutions. Demographic, laboratory and clinical data were recorded, including clinical outcomes. Results: Of 81 COVID-positive patients, the average age was 61 years, 42 (52%) women and 45 (55%) had positive abdominopelvic findings. The most common abdominal imaging features were intestinal imaging findings (20/81, 24%), including colorectal (4/81, 5%) and small bowel thickening (10/81, 12%), intestinal distension (15/81, 18%), pneumatosis (1/81, 1%) and intestinal perforation (1/81, 1%). On multivariate analysis, intestinal imaging findings were associated with higher risk of worse outcome (death or invasive mechanical ventilation) (RR = 2.6, p = 0.04) and higher risk of invasive mechanical ventilation alone (RR = 6.2, p = 0.05). Conclusion: Intestinal abnormalities were common findings in COVID-19 patients who underwent abdominal CT and were significantly correlated to worse outcomes in the clinical follow-up.
- Mucinous Degeneration on MRI After Neoadjuvant Therapy in Patients With Rectal Adenocarcinoma: Frequency and Association With Clinical Outcomes(2023) MIRANDA, Joao; PINTO, Paulo Victor Alves; KINOCHITA, Fernanda; GARCIA, Camila Marchiolli; HOMSI, Maria El; OLIVEIRA, Camila Vilela de; PANDINI, Rafael Vaz; NAHAS, Caio Sergio Rizkallah; NAHAS, Sergio C.; GOLLUB, Marc J.; HORVAT, NatallyBACKGROUND. Patients with nonmucinous rectal adenocarcinoma may develop mucinous changes after neoadjuvant chemoradiotherapy, which are described as mucinous degeneration. The finding's significance in earlier studies has varied. OBJECTIVE. The purpose of this study was to assess the frequency of mucinous degeneration on MRI after neoadjuvant therapy for rectal adenocarcinoma and to compare outcomes among patients with nonmucinous tumor, mucinous tumor, and mucinous degeneration on MRI. METHODS. This retrospective study included 201 patients (83 women, 118 men; mean age, 61.8 +/- 2.2 [SD] years) with rectal adenocarcinoma who underwent neoadjuvant chemoradiotherapy followed by total mesorectal excision from October 2011 to November 2015, underwent baseline and restaging rectal MRI examinations, and had at least 2 years of follow-up. Two radiologists independently evaluated MRI examinations for mucin content, which was defined as T2 hyperintensity in the tumor or tumor bed, and resolved differences by consensus. Patients were classified into three groups on the basis of mucin status: those with nonmucinous tumor (<= 50% mucin content on baseline and restaging examinations), those with mucinous tumor (> 50% mucin content on baseline and restaging examinations), and those with mucinous degeneration (<= 50% mucin content on baseline examination and > 50% content on restaging examination). The three groups were compared. RESULTS. Interreader agreement for mucin content, expressed as a kappa coefficient, was 0.893 on baseline MRI and 0.890 on restaging MRI. Of the 201 patients, 156 (77.6%) had nonmucinous tumor, 34 (16.9%) had mucinous tumor, and 11 (5.5%) had mucinous degeneration. Mucin status was not significantly associated with complete pathologic response (p = .41) or local or distant recurrence (both p > .05). The death rate during follow-up was not significantly different (p = .21) between patients with non-mucinous tumor (23.1%), those with mucinous tumor (29.4%), and those with mucinous degeneration (9.1%). In adjusted Cox regression analysis, with mucinous degeneration used as reference, the HR for the overall survival rate for the mucinous tumor group was 4.7 (95% CI, 0.6-38.3; p = .14), and that for the nonmucinous tumor group was 8.0 (95% CI, 0.9-59.9; p = .06). On histopathologic assessment, all 11 patients with mucinous degeneration showed acellular mucin, yet 10 of 11 patients showed viable tumor (i.e., in non-mucinous portions of the tumors). CONCLUSION. Mucinous degeneration on MRI is not significantly associated with pathologic complete response, recurrence, or survival. CLINICAL IMPACT. Mucinous degeneration on MRI is uncommon and should not be deemed an indicator of pathologic complete response.