PURPOSE: The purpose of this work was to define the optimal margins for gadolinium-enhanced T(1)-weighted magnetic resonance imaging (Gd-MRI) and T(2)-weighted MRI (T(2)-MRI) for delineating target volumes in planning radiation therapy for postoperative patients with newly diagnosed glioblastoma multiforme (GBM) by comparison to carbon-11-labeled methionine positron emission tomography ([(11)C]MET-PET) findings. METHODS AND MATERIALS: Computed tomography (CT), MRI, and [(11)C]MET-PET were separately performed for radiation therapy planning for 32 patients newly diagnosed with GBM within 2 weeks after undergoing surgery. The extent of Gd-MRI (Gd-enhanced clinical target volume [CTV-Gd]) uptake and that of T(2)-MRI of the CTV (CTV-T(2)) were compared with the extent of [(11)C]MET-PET (CTV--[(11)C]MET-PET) uptake by using CT--MRI or CT--[(11)C]MET-PET fusion imaging. We defined CTV-Gd (x mm) and CTV-T(2) (x mm) as the x-mm margins (where x = 0, 2, 5, 10, and 20 mm) outside the CTV-Gd and the CTV-T(2), respectively. We evaluated the relationship between CTV-Gd (x mm) and CTV-- [(11)C]MET-PET and the relationship between CTV-T(2) (x mm) and CTV-- [(11)C]MET-PET. RESULTS: The sensitivity of CTV-Gd (20 mm) (86.4%) was significantly higher than that of the other CTV-Gd. The sensitivity of CTV-T(2) (20 mm) (96.4%) was significantly higher than that of the other CTV-T(2) (x = 0, 2, 5, 10 mm). The highest sensitivity and lowest specificity was found with CTV-T(2) (x = 20 mm). CONCLUSIONS: It is necessary to use a margin of at least 2 cm for CTV-T(2) for the initial target planning of radiation therapy. However, there is a limit to this setting in defining the optimal margin for Gd-MRI and T(2)-MRI for the precise delineation of target volumes in radiation therapy planning for postoperative patients with GBM.
PURPOSE: The purpose of this work was to define the optimal margins for gadolinium-enhanced T(1)-weighted magnetic resonance imaging (Gd-MRI) and T(2)-weighted MRI (T(2)-MRI) for delineating target volumes in planning radiation therapy for postoperative patients with newly diagnosed glioblastoma multiforme (GBM) by comparison to carbon-11-labeled methionine positron emission tomography ([(11)C]MET-PET) findings. METHODS AND MATERIALS: Computed tomography (CT), MRI, and [(11)C]MET-PET were separately performed for radiation therapy planning for 32 patients newly diagnosed with GBM within 2 weeks after undergoing surgery. The extent of Gd-MRI (Gd-enhanced clinical target volume [CTV-Gd]) uptake and that of T(2)-MRI of the CTV (CTV-T(2)) were compared with the extent of [(11)C]MET-PET (CTV--[(11)C]MET-PET) uptake by using CT--MRI or CT--[(11)C]MET-PET fusion imaging. We defined CTV-Gd (x mm) and CTV-T(2) (x mm) as the x-mm margins (where x = 0, 2, 5, 10, and 20 mm) outside the CTV-Gd and the CTV-T(2), respectively. We evaluated the relationship between CTV-Gd (x mm) and CTV-- [(11)C]MET-PET and the relationship between CTV-T(2) (x mm) and CTV-- [(11)C]MET-PET. RESULTS: The sensitivity of CTV-Gd (20 mm) (86.4%) was significantly higher than that of the other CTV-Gd. The sensitivity of CTV-T(2) (20 mm) (96.4%) was significantly higher than that of the other CTV-T(2) (x = 0, 2, 5, 10 mm). The highest sensitivity and lowest specificity was found with CTV-T(2) (x = 20 mm). CONCLUSIONS: It is necessary to use a margin of at least 2 cm for CTV-T(2) for the initial target planning of radiation therapy. However, there is a limit to this setting in defining the optimal margin for Gd-MRI and T(2)-MRI for the precise delineation of target volumes in radiation therapy planning for postoperative patients with GBM.
Authors: Tim J Kruser; Walter R Bosch; Shahed N Badiyan; Joseph A Bovi; Amol J Ghia; Michelle M Kim; Abhishek A Solanki; Sean Sachdev; Christina Tsien; Tony J C Wang; Minesh P Mehta; Kevin P McMullen Journal: J Neurooncol Date: 2019-03-19 Impact factor: 4.130
Authors: Christopher L Tinkle; Elizabeth C Duncan; Mikhail Doubrovin; Yuanyuan Han; Yimei Li; Hyun Kim; Alberto Broniscer; Scott E Snyder; Thomas E Merchant; Barry L Shulkin Journal: J Nucl Med Date: 2018-08-02 Impact factor: 10.057