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
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- 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.
- F-18-FDG PET/CT Osteometabolic Activity in Metastatic Parathyroid Carcinoma(2016) VALE, Romulo Hermeto Bueno do; QUEIROZ, Marcelo Araujo; COUTINHO, Artur Martins Novaes; BUCHPIGUEL, Carlos Alberto; MENEZES, Marcos Roberto deParathyroid cancer is an uncommon type of malignancy, which is frequently associated with poor prognosis. Clinical manifestations are caused by elevated serum calcium and parathyroid hormone (PTH). Diagnostic imaging studies as neck ultrasonography, technetium Tc Tc-99m-sestamibi whole body scintigraphy, CT, and MR are already established tools for this malignancy. Nevertheless, the role of F-18-FDG PET/CT remains unknown in this scenario, with few published studies in literature. Hence, in this article, we aimed to report an illustrative case of increased skeletal FDG uptake associated with high calcium and PTH levels.
- 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.