Proposal of a New 18F-FDG PET/CT Predictor of Response in Rectal Cancer Treated by Neoadjuvant Chemoradiation Therapy and Comparison With PERCIST Criteria

Section: Discussionmentioning

confidence: 99%

The Role of Routine Clinical Pretreatment 18F-FDG PET/CT in Predicting Outcome of Colorectal Liver Metastasis

Tam¹,

Cook²,

Chau³

et al. 2015

“…SUL mean of the liver is usually measured by placing a spherical volume of interest (VOI) in the right lobe of liver. Liver SUV mean has also been utilized as normalization factor in PET derived quantitative therapy response formulations, which were further adapted to assess residual disease in colorectal malignancy [3,4]. In our previous work[5], we demonstrated that Liver SUL mean has almost perfect inter-reader reliability, regardless of whether the volume of interest (VOI) is placed at the upper, lower, or portal vein level of the right lobe of the liver and the inter reader variability is least in the upper aspect of the right lobe of the liver.…”

Section: Introductionmentioning

confidence: 99%

Liver Standardized Uptake Value Corrected for Lean Body Mass at FDG PET/CT

Chirindel¹,

Alluri²,

Tahari³

et al. 2015

Objective To establish the magnitude change and inter-reader reliability of Liver SULmean in dual time point imaging at 1 and 2 hours and 1 and 4 hours. Methods Early and Delayed FDG PET/CT scans were included for 28 patients (13 males and 15 females) who had normal liver by CT or US. The average uptake time between the early and delayed scans were 55 minutes (range 44-69) for pancreatic adenocarcinoma patients (n = 19) and 184 minutes (range 140-197) for neurofibromatosis (NF) patients (n = 9). 30-mm- diameter spherical VOI was placed within the right lobe of the liver above, below, and at the level of the main portal vein by two independent readers. Correlation coefficients, Analysis of variance, intraclass correlation coefficient (ICC), and Bland-Altman analysis were performed. Results The mean liver SULmean was between 1.39 and 1.42 and between 1.28 and 1.3 in early and delayed images, respectively (p = 0.001). There is time dependent reduction in the mean Liver SULmean at 2 hour (7-8%) and four hour uptake time (15-21%), compared to one hour. The correlation coefficient between delayed uptake time and Liver SULmean reduction is 0.39 to 0.41 at the upper aspect of liver. The ICC for two readers varied between 0.997 and 0.998 and between 0.995 and 0.999 in early and delayed images, respectively (p=0.001). Conclusion There is time dependent reduction of mean Liver SULmean, about 7-8% within the clinically relevant FDG uptake time, in the same patient with excellent inter-reader agreement in early and delayed images within the right lobe of the liver. Therefore Liver SULmean could represent a useful reference parameter in quantitative analysis of dual-phase FDG PET/CT in malignancy or atypical infection/inflammatory disease. Furthermore, it may be suitable as normalization factor in currently available formulae quantifying therapy response on PET imaging.

“…There has been need for standardization of 18 34,35 In the future, these newly proposed criteria for tumor response and volume segmentation system should be used.…”

Section: Discussionmentioning

confidence: 99%

Volumetric Parameters Changes of Sequential 18F-FDG PET/CT for Early Prediction of Recurrence and Death in Patients With Locally Advanced Rectal Cancer Treated With Preoperative Chemoradiotherapy

Kim

Chang

2015