Author of 2 Presentations
SS 7.3 - Comparison of diffusion-weighted MRI and 68Ga-DOTATATE PET/CT to assess treatment response of hepatic metastases of primary neuroendocrine tumors undergoing selective internal radiotherapy with 90Yttrium-microspheres
Abstract
Purpose
To compare SUV of 68Ga-DOTATATE PET/CT and ADC values of diffusion-weighted MRI (DWI) in assessing tumor response in patients with liver metastases of primary neuroendocrine tumors (NET) following radioembolization.
Material and methods
30 patients with 80 hepatic lesions of primary NET who underwent 68Ga-DOTATATE PET/CT and abdominal MRI with DWI before and after selective internal radiotherapy (SIRT) were included. Tumor size, intralesional ADCmin and ADCmean, ADCmean of normal liver parenchyma, intralesional SUVmax and SUVmean, tumor to spleen ratio (T/S ratio) and tumor to liver ratio (T/L ratio) were measured. Treatment response was evaluated with respect to Response Evaluation Criteria in Solid Tumors v1.1 (RECIST) on follow-up examination.
Results
67/80 metastases were classified as stable disease (SD) and 13/80 metastases as partial response (PR). Intralesional ADCmin and ADCmean values increased significantly (p< 0.006) after SIRT in the group of PR and SD with a significant higher increase of ADCmin values in the PR group (54.1 ± 14.6 % vs. 24 ± 4.9 %, p= 0.02). Currently used SUV measurements showed significant decrease in the PR group (including SUV max, SUVmean, T/S ratio and T/L ratio), while in the SD group, only SUVmax, SUVmean and T/S ratio (max/max) decreased significantly. Using ROC curves, SUVmean was found to be the best metric (AUC 0.75); however, similar results were found for ADCmin (AUC 0.7).
Conclusion
DW-MRI appears to perform similar to 68Ga-DOTATATE PET/CT for quantitative response assessment in patients with liver metastases of NET who undergo SIRT and may represent a valuable functional marker to guide further treatment decisions in these patients.
Video-on-demand
SS 7.6 - Monitoring treatment response after CT-guided high-dose-rate brachytherapy in patients with cholangiocarcinoma using apparent diffusion coefficients
Abstract
Purpose
The aim of this study was to evaluate the ability of apparent diffusion coefficient (ADC) measurements to predict treatment response after CT-guided high-dose-rate (HDR) brachytherapy in patients with cholangiocarcinoma.
Material and methods
This retrospective pilot study included 14 patients with 20 hepatic lesions of cholangiocarcinoma who were treated by HDR brachytherapy. Pre- and postinterventional MRI including diffusion-weighted imaging (b-values= 50, 400 and 800 s/mm², mean time before and after brachytherapy: 14 days and 99 days, respectively) were performed. Tumor size, tumor enhancement, minimum, maximum and mean ADC values (ADC min, max, mean) of the lesions as well as ADC mean of normal liver parenchyma were analyzed and compared before and after brachytherapy. Treatment response was evaluated based on modified Response Evaluation Criteria in Solid Tumors (mRECIST).
Results
According to mRECIST, 14 (70%) lesions were characterized as responder and 6 (30%) as non-responder at the time of the first MRI after brachytherapy. ADC values of responding lesions increased significantly after brachytherapy (ADC max p<0.001; ADC mean p<0.001; ADC min p<0.05), whereas non-responding lesions showed no significant change. Furthermore, the ADC max values after brachytherapy were significantly higher in lesions with response than in lesions with non-response (p<0.05).
Conclusion
In patients with cholangiocarcinoma, HDR brachytherapy enables local tumor control. By measuring ADC values, particularly ADC max and mean values, therapeutic response can be monitored. This may be a useful adjunct to morphologic changes such as size and enhancement.
Video-on-demand
Presenter of 1 Presentation
SS 7.3 - Comparison of diffusion-weighted MRI and 68Ga-DOTATATE PET/CT to assess treatment response of hepatic metastases of primary neuroendocrine tumors undergoing selective internal radiotherapy with 90Yttrium-microspheres
Abstract
Purpose
To compare SUV of 68Ga-DOTATATE PET/CT and ADC values of diffusion-weighted MRI (DWI) in assessing tumor response in patients with liver metastases of primary neuroendocrine tumors (NET) following radioembolization.
Material and methods
30 patients with 80 hepatic lesions of primary NET who underwent 68Ga-DOTATATE PET/CT and abdominal MRI with DWI before and after selective internal radiotherapy (SIRT) were included. Tumor size, intralesional ADCmin and ADCmean, ADCmean of normal liver parenchyma, intralesional SUVmax and SUVmean, tumor to spleen ratio (T/S ratio) and tumor to liver ratio (T/L ratio) were measured. Treatment response was evaluated with respect to Response Evaluation Criteria in Solid Tumors v1.1 (RECIST) on follow-up examination.
Results
67/80 metastases were classified as stable disease (SD) and 13/80 metastases as partial response (PR). Intralesional ADCmin and ADCmean values increased significantly (p< 0.006) after SIRT in the group of PR and SD with a significant higher increase of ADCmin values in the PR group (54.1 ± 14.6 % vs. 24 ± 4.9 %, p= 0.02). Currently used SUV measurements showed significant decrease in the PR group (including SUV max, SUVmean, T/S ratio and T/L ratio), while in the SD group, only SUVmax, SUVmean and T/S ratio (max/max) decreased significantly. Using ROC curves, SUVmean was found to be the best metric (AUC 0.75); however, similar results were found for ADCmin (AUC 0.7).
Conclusion
DW-MRI appears to perform similar to 68Ga-DOTATATE PET/CT for quantitative response assessment in patients with liver metastases of NET who undergo SIRT and may represent a valuable functional marker to guide further treatment decisions in these patients.
Video-on-demand
Author of 2 Presentations
SS 7.3 - Comparison of diffusion-weighted MRI and 68Ga-DOTATATE PET/CT to assess treatment response of hepatic metastases of primary neuroendocrine tumors undergoing selective internal radiotherapy with 90Yttrium-microspheres (ID 459)
Abstract
Purpose
To compare SUV of 68Ga-DOTATATE PET/CT and ADC values of diffusion-weighted MRI (DWI) in assessing tumor response in patients with liver metastases of primary neuroendocrine tumors (NET) following radioembolization.
Material and methods
30 patients with 80 hepatic lesions of primary NET who underwent 68Ga-DOTATATE PET/CT and abdominal MRI with DWI before and after selective internal radiotherapy (SIRT) were included. Tumor size, intralesional ADCmin and ADCmean, ADCmean of normal liver parenchyma, intralesional SUVmax and SUVmean, tumor to spleen ratio (T/S ratio) and tumor to liver ratio (T/L ratio) were measured. Treatment response was evaluated with respect to Response Evaluation Criteria in Solid Tumors v1.1 (RECIST) on follow-up examination.
Results
67/80 metastases were classified as stable disease (SD) and 13/80 metastases as partial response (PR). Intralesional ADCmin and ADCmean values increased significantly (p< 0.006) after SIRT in the group of PR and SD with a significant higher increase of ADCmin values in the PR group (54.1 ± 14.6 % vs. 24 ± 4.9 %, p= 0.02). Currently used SUV measurements showed significant decrease in the PR group (including SUV max, SUVmean, T/S ratio and T/L ratio), while in the SD group, only SUVmax, SUVmean and T/S ratio (max/max) decreased significantly. Using ROC curves, SUVmean was found to be the best metric (AUC 0.75); however, similar results were found for ADCmin (AUC 0.7).
Conclusion
DW-MRI appears to perform similar to 68Ga-DOTATATE PET/CT for quantitative response assessment in patients with liver metastases of NET who undergo SIRT and may represent a valuable functional marker to guide further treatment decisions in these patients.
Video-on-demand
SS 7.6 - Monitoring treatment response after CT-guided high-dose-rate brachytherapy in patients with cholangiocarcinoma using apparent diffusion coefficients (ID 718)
Abstract
Purpose
The aim of this study was to evaluate the ability of apparent diffusion coefficient (ADC) measurements to predict treatment response after CT-guided high-dose-rate (HDR) brachytherapy in patients with cholangiocarcinoma.
Material and methods
This retrospective pilot study included 14 patients with 20 hepatic lesions of cholangiocarcinoma who were treated by HDR brachytherapy. Pre- and postinterventional MRI including diffusion-weighted imaging (b-values= 50, 400 and 800 s/mm², mean time before and after brachytherapy: 14 days and 99 days, respectively) were performed. Tumor size, tumor enhancement, minimum, maximum and mean ADC values (ADC min, max, mean) of the lesions as well as ADC mean of normal liver parenchyma were analyzed and compared before and after brachytherapy. Treatment response was evaluated based on modified Response Evaluation Criteria in Solid Tumors (mRECIST).
Results
According to mRECIST, 14 (70%) lesions were characterized as responder and 6 (30%) as non-responder at the time of the first MRI after brachytherapy. ADC values of responding lesions increased significantly after brachytherapy (ADC max p<0.001; ADC mean p<0.001; ADC min p<0.05), whereas non-responding lesions showed no significant change. Furthermore, the ADC max values after brachytherapy were significantly higher in lesions with response than in lesions with non-response (p<0.05).
Conclusion
In patients with cholangiocarcinoma, HDR brachytherapy enables local tumor control. By measuring ADC values, particularly ADC max and mean values, therapeutic response can be monitored. This may be a useful adjunct to morphologic changes such as size and enhancement.
Video-on-demand
Presenter of 1 Presentation
SS 7.3 - Comparison of diffusion-weighted MRI and 68Ga-DOTATATE PET/CT to assess treatment response of hepatic metastases of primary neuroendocrine tumors undergoing selective internal radiotherapy with 90Yttrium-microspheres (ID 459)
Abstract
Purpose
To compare SUV of 68Ga-DOTATATE PET/CT and ADC values of diffusion-weighted MRI (DWI) in assessing tumor response in patients with liver metastases of primary neuroendocrine tumors (NET) following radioembolization.
Material and methods
30 patients with 80 hepatic lesions of primary NET who underwent 68Ga-DOTATATE PET/CT and abdominal MRI with DWI before and after selective internal radiotherapy (SIRT) were included. Tumor size, intralesional ADCmin and ADCmean, ADCmean of normal liver parenchyma, intralesional SUVmax and SUVmean, tumor to spleen ratio (T/S ratio) and tumor to liver ratio (T/L ratio) were measured. Treatment response was evaluated with respect to Response Evaluation Criteria in Solid Tumors v1.1 (RECIST) on follow-up examination.
Results
67/80 metastases were classified as stable disease (SD) and 13/80 metastases as partial response (PR). Intralesional ADCmin and ADCmean values increased significantly (p< 0.006) after SIRT in the group of PR and SD with a significant higher increase of ADCmin values in the PR group (54.1 ± 14.6 % vs. 24 ± 4.9 %, p= 0.02). Currently used SUV measurements showed significant decrease in the PR group (including SUV max, SUVmean, T/S ratio and T/L ratio), while in the SD group, only SUVmax, SUVmean and T/S ratio (max/max) decreased significantly. Using ROC curves, SUVmean was found to be the best metric (AUC 0.75); however, similar results were found for ADCmin (AUC 0.7).
Conclusion
DW-MRI appears to perform similar to 68Ga-DOTATATE PET/CT for quantitative response assessment in patients with liver metastases of NET who undergo SIRT and may represent a valuable functional marker to guide further treatment decisions in these patients.