MARCELO ARAUJO QUEIROZ
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
LIM/43 - Laboratório de Medicina Nuclear, Hospital das Clínicas, Faculdade de Medicina
7 resultados
Resultados de Busca
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- Revisiting Prostate Cancer Recurrence with PSMA PET: Atlas of Typical and Atypical Patterns of Spread(2019) BARBOSA, Felipe G.; QUEIROZ, Marcelo A.; NUNES, Rafael F.; VIANA, Publio C. C.; MARIN, Jose Flavio G.; CERRI, Giovanni G.; BUCHPIGUEL, Carlos A.The introduction of prostate-specific membrane antigen (PSMA) in clinical practice has revolutionized evaluation of biochemical recurrence of prostate cancer after curative-intent treatment. The high expression of this glycoprotein in prostate cancer cells makes PSMA imaging superior to the current conventional staging methods, namely bone scanning and CT. The high capability of PSMA imaging for identifying very small previously undetected lesions has been widely demonstrated in the literature, leading to a rethinking of patient management by oncologists, urologists, and radiation oncologists. The typical and predictable patterns of spread in prostate cancer are still more prevalent, such as spread to pelvic lymph nodes and bone metastasis, but different patterns of disease spread are becoming more commonly recognized with higher reliability because PSMA imaging allows detection of more typical and atypical lesions than conventional imaging. Furthermore, it is important for the reading physician to recognize and understand the typical disease spread and the most prevalent atypical prostate cancer relapses, not only to heighten the relevancy of reports but also to improve imaging consultancy in multispecialty oncologic practice. (C) RSNA, 2019.
- Reassessing Patterns of Response to Immunotherapy with PET: From Morphology to Metabolism(2021) COSTA, Larissa B.; QUEIROZ, Marcelo A.; BARBOSA, Felipe G.; NUNES, Rafael F.; ZANIBONI, Elaine C.; RUIZ, Mariana Mazo; JARDIM, Denis; MARIN, Jose Flavio Gomes; CERRI, Giovanni G.; BUCHPIGUEL, Carlos A.Cancer demands precise evaluation and accurate and timely assessment of response to treatment. Imaging must be performed early during therapy to allow adjustments to the course of treatment. For decades, cross-sectional imaging provided these answers, showing responses to the treatment through changes in tumor size. However, with the emergence of immune checkpoint inhibitors, complex immune response patterns were revealed that have quickly highlighted the limitations of this approach. Patterns of response beyond tumor size have been recognized and include cystic degeneration, necrosis, hemorrhage, and cavitation. Furthermore, new unique patterns of response have surfaced, like pseudoprogression and hyperprogression, while other patterns were shown to be deceptive, such as unconfirmed progressive disease. This evolution led to new therapeutic evaluation criteria adapted specifically for immunotherapy. Moreover, inflammatory adverse effects of the immune checkpoint blockade were identified, many of which were life threatening and requiring prompt intervention. Given complex concepts like tumor microenvironment and novel therapeutic modalities in the era of personalized medicine, increasingly sophisticated imaging techniques are required to address the intricate patterns of behavior of different neoplasms. Fluorine 18-fluorodeoxyglucose PET/CT has rapidly emerged as one such technique that spans both molecular biology and immunology. This imaging technique is potentially capable of identifying and tracking prognostic biomarkers owing to its combined use of anatomic and metabolic imaging, which enables it to characterize biologic processes in vivo. This tailored approach may provide whole-body quantification of the metabolic burden of disease, providing enhanced prediction of treatment response and improved detection of adverse events. (C) RSNA, 2020
- Theranostics in Nuclear Medicine: Emerging and Re-emerging Integrated Imaging and Therapies in the Era of Precision Oncology(2020) MARIN, Jose Flavio Gomes; NUNES, Rafael F.; COUTINHO, Artur M.; ZANIBONI, Elaine C.; COSTA, Larissa B.; BARBOSA, Felipe G.; QUEIROZ, Marcelo A.; CERRI, Giovanni G.; BUCHPIGUEL, Carlos A.Theranostics refers to the pairing of diagnostic biomarkers with therapeutic agents that share a specific target in diseased cells or tissues. Nuclear medicine, particularly with regard to applications in oncology, is currently one of the greatest components of the theranostic concept in clinical and research scenarios. Theranostics in nuclear medicine, or nuclear theranostics, refers to the use of radioactive compounds to image biologic phenomena by means of expression of specific disease targets such as cell surface receptors or membrane transporters, and then to use specifically designed agents to deliver ionizing radiation to the tissues that express these targets. The nuclear theranostic approach has sparked increasing interest and gained importance in parallel to the growth in molecular imaging and personalized medicine, helping to provide customized management for various diseases; improving patient selection, prediction of response and toxicity, and determination of prognosis; and avoiding futile and costly diagnostic examinations and treatment of many diseases. The authors provide an overview of theranostic approaches in nuclear medicine, starting with a review of the main concepts and unique features of nuclear theranostics and aided by a retrospective discussion of the progress of theranostic agents since early applications, with illustrative cases emphasizing the imaging features. Advanced concepts regarding the role of fluorine 18-fluorodeoxyglucose PET in theranostics, as well as developments in and future directions of theranostics, are discussed. (C) RSNA, 2020
- PET/MRI Characterization of Mucinous Versus Nonmucinous Components of Rectal Adenocarcinoma: A Comparison of Tumor Metabolism and Cellularity(2021) QUEIROZ, Marcelo A.; NAVES, Anarosa; DREYER, Priscilla R.; CERRI, Giovanni G.; BUCHPIGUEL, Carlos A.OBJECTIVE. The purpose of this study was to evaluate whether FDG PET/MRI can be used to differentiate the mucinous from the nonmucinous components of primary rectal tumors and to compare the glycolytic metabolism on PET with tumor cellularity on DWI in both components. SUBJECTS AND METHODS. Ninety-nine patients who underwent FDG PET/MRI for staging of primary rectal cancer were included in this prospective analysis. MRI depicted the mucin component through the tumor volume. Separate volumes of interest were drawn on both mucinous and nonmucinous components and propagated to PET and apparent diffusion coefficient (ADC) mapping. Maximum and mean standardized uptake values (SUVmax, SUVmean) and maximum, mean, and minimum ADC values (ADC(max), ADC(mean), ADC(min)) were recorded and compared between areas with mucinous and nonmucinous components. Whole-body PET/MRI was also used to evaluate for the presence of distant metastases. Nonparametric testing was used to compare the two groups of patients: those with tumors with a mucinous component and those with tumors without a mucinous component. Logistic regression analysis was performed to calculate the association risk between mucinous component and metastatic disease. RESULTS. Seventeen patients (17.2%) had a mucinous component within the tumor on T2-weighted MRI. Most of these patients had advanced disease, the mucinous component tumors being in significantly higher T categories than the tumors without a mucinous component (88.2% vs 61.0%; p = 0.032). SUVmax (7.4 vs 16.7; p = 0.002) and SUVmean (5.4 vs 13.4; p = 0.001) were significantly lower in tumors with a mucinous component than in those without a mucinous component. Tumor ADC measurements were not different between tumors with and those without a mucinous component (ADC mean, 1.4 vs 1.6; p = 0.361). There was no association between presence of a mucinous component within the primary rectal tumor and presence of synchronous metastases (odds ratio, 1.1 [0.4-3.0]; p = 0.904). Moreover, the occurrence of metastases in patients with mucinous component tumors (7/17 [41.2%]) was not different from that in patients with tumors without a mucinous component (28/82 [34.1%]) (p = 0.887). CONCLUSION. PET/MRI can be used to differentiate the mucinous and nonmucinous components within primary rectal adenocarcinoma on the basis of metabolic status. The FDG uptake is significantly lower in the mucinous component, but tumor cellularity based on MRI and DWI findings is not. Despite being associated with a higher T category in the sample of patients in this study, the presence of a mucinous component seems not to be associated with increased risk of synchronous metastases.
- Value of Primary Rectal Tumor PET/MRI in the Prediction of Synchronic Metastatic Disease(2022) QUEIROZ, Marcelo A.; ORTEGA, Cinthia D.; FERREIRA, Felipe R.; CAPARELI, Fernanda C.; NAHAS, Sergio C.; CERRI, Giovanni G.; BUCHPIGUEL, Carlos A.Purpose: To analyze the associations between positron emission tomography (PET)/magnetic resonance imaging (MRI) features for primary rectal tumors and metastases. Procedures: Between November 2016 and April 2018, 101 patients with rectal adenocarcinoma were included in this prospective study (NCT02537340) for whole-body PET/MRI for baseline staging. Two readers analyzed the PET/MRI; they assessed the semiquantitative PET features of the primary tumor and the N- and M-stages. Another reader analyzed the MRI features for locoregional staging. The reference standard for confirming metastatic disease was biopsy or imaging follow-up. Nonparametric tests were used to compare the PET/MRI features of the participants with or without metastatic disease. Binary logistic regression was used to evaluate the associations between the primary tumor PET/MRI features and metastatic disease. Results: A total of 101 consecutive participants (median age 62 years; range: 33-87 years) were included. Metastases were detected in 35.6% (36 of 101) of the participants. Among the PET/MRI features, higher tumor lesion glycolysis (352.95 vs 242.70; P =.46) and metabolic tumor volume (36.15 vs 26.20; P =.03) were more frequent in patients with than in those without metastases. Additionally, patients with metastases had a higher incidence of PET-positive (64% vs 32%; P =.009) and MRIpositive (56% vs 32%; P =.03) mesorectal lymph nodes, extramural vascular invasion (86% vs 49%; P >.001), and involvement of mesorectal fascia (64% vs 42%; P =.04); there were also differences between the mrT stages of these two groups (P =.008). No differences in the maximum standardized uptake values for the primary tumors in patients with and without metastases were observed (18.9 vs 19.1; P =.56). Multivariable logistic regression showed that extramural vascular invasion on MRI was the only significant predictor (adjusted odds ratio, 3.8 [95% CI: 1.1, 13.9]; P =.001). Conclusion: PET/MRI facilitated the identification of participants with a high risk of metastatic disease, though these findings were based mainly on MRI features.
- Diagnostic accuracy of FDG-PET/MRI versus pelvic MRI and thoracic and abdominal CT for detecting synchronous distant metastases in rectal cancer patients(2021) QUEIROZ, Marcelo A.; ORTEGA, Cinthia D.; FERREIRA, Felipe R.; NAHAS, Sergio C.; CERRI, Giovanni G.; BUCHPIGUEL, Carlos A.Purpose We compared the diagnostic accuracy of detecting distant metastases for baseline rectal cancer staging between PET/MRI and conventional staging (CS). Materials and methods This prospective study from November 2016 to April 2018 included 101 rectal adenocarcinoma patients for primary staging. These patients underwent whole-body PET/MRI in addition to CS (pelvic MRI and thoracic and abdominal contrast-enhanced CT). Different readers analyzed CS and PET/MRI findings for primary tumor, nodal, and metastatic staging. The presence, number, and location of metastases were recorded according to the organ involved (non-regional lymph nodes (LNs), liver, lungs, or others). Lesions were defined as positive, negative, or indeterminate. The number of lesions per organ was limited to 10. The McNemar test was used to compare the accuracies. Results PET/MRI exhibited a higher accuracy in detecting metastatic disease than CS in all patients (88.4% vs. 82.6%,p = 0.003) and in patients with extramural vascular invasion (EMVI) (88.9% vs. 85.5%,p = 0.013). The detection rate of PET/MRI was superior to that of CS for all lesions [84.1% vs. 68.9%,p = 0.001], as well as those in the liver (89.2% vs. 84.2%), non-regional LNs (90.0% vs. 36.7%), and lungs (76.4% vs. 66.9%). PET/MRI correctly classified 19/33 (57.5%) patients with indeterminate lesions on CS. Conclusion PET/MRI yields higher accuracy than CS for detecting distant synchronous metastases in the baseline staging of patients with rectal cancer and EMVI. PET/MRI exhibited a higher detection rate than CS for identifying non-regional LNs, hepatic lesions, and pulmonary lesions as well as correctly classifying patients with indeterminate lesions.
- Value of Primary Rectal Tumor PET/MRI in the Prediction of Synchronic Metastatic Disease (vol 24, pg 453, 2021)(2022) QUEIROZ, Marcelo A.; ORTEGA, Cinthia D.; FERREIRA, Felipe R.; CAPARELI, Fernanda C.; NAHAS, Sergio C.; CERRI, Giovanni G.; BUCHPIGUEL, Carlos A.