Semi-quantitative F-18-FDG PET/computed tomography parameters for prediction of grade in patients with renal cell carcinoma and the incremental value of diuretics

Abstract

Objective The primary objective of the study was to evaluate the correlation between semi-quantitative F-18 FDG PET parameters and renal cell carcinoma (RCC) grade and its role in predicting the histopathological grade in RCC. The secondary objective was to evaluate the role of forced diuresis in improving the diagnostic accuracy of F-18 FDG for RCC. Methods Thirty-three patients with radiologically proven RCC were included in the study. All patients underwent PET/CT on a dedicated PET/CT scanner (Biograph mCT; Siemens Medical Solutions, Erlangen, Germany) 45–60 min post-injection F-18-FDG. Patients were then injected 1 mg/kg body weight furosemide (upto 40 mg) and regional PET/CT images of abdomen were acquired after 2 h. For both baseline and post-diuretic F-18-FDG PET/CT scans, maximum standardized uptake value for tumor (SUVmax), mean SUV for tumor, metabolic tumor volume (MTV), tumor-to-liver (T/L) and tumor-to-kidney ratio (T/K) were calculated. Histopathology findings were considered as the reference standard. To assess the incremental value of diuresis in scan interpretation, visual analysis of scans was done. Results Of 33 patients, histopathology grading was available for comparison with metabolic tumor markers in all except four. Of 29 patients (mean age = 51.89 ± 13.54 years), 20 patients had clear cell (cc) type while rest had non-cc RCC. Difference between the mean values among the categories was insignificant for all parameters except T/K. Fuhrman grading was obtained in 25 patients (17 low and eight high). SUVmax, MTV and T/L were found to be significantly different between low and high grade patients. Significantly strong positive correlation was observed between Furhman grades and tumor metabolism (r ≥ 0.5). No significant difference was observed between baseline and post-diuretic scan in any of the patients. Conclusion Semi-quantitative F-18 FDG PET parameters (SUVmax, MTV and T/L) were found to be significantly correlated with Fuhrman grade in patients with RCC and are important markers for differentiation between low- and high-grade tumors. Furthermore, forced diuresis had no incremental value in characterization of primary RCC lesions.

18F-FDG texture analysis predicts the pathological Fuhrman nuclear grade of clear cell renal cell carcinoma

“…But this does not mean that PET/CT examination is useless for the diagnosis of ccRCC. A number of studies have shown that the value of maximum standardized uptake value (SUVmax) as the traditional PET/ CT parameter has a certain correlation with the Fuhrman grade of pathology [10][11][12].…”

Metabolic tumour volume on 18F-FDG PET/CT predicts extended pathological T stages in patients with renal cell carcinoma at staging

“…Previous studies have found that high 18 F-FDG uptake in RCCs is associated with high ISUP grades 30 . In addition to ISUP grade, LVI has been added as a new prognostic factor for cancer-specific survival and metastasis-free survival in RCC cases 29 .…”

The effects of baicalin on piglets challenged with Glaesserella parasuis

“…Seven days after the G. parasuis SH0165 challenge, the brains and lungs of the surviving piglets from all groups were isolated, fixed in 10% neutral-buffered formalin, and embedded in paraffin. Tissue sections (4 μm thick) were stained with haematoxylin and eosin with the standard method and observed with light microscopy [ 25 ].…”