PURPOSE: To compare patterns of disease failure among patients treated with intensity-modulated radiotherapy (IMRT) in conjunction with daily image-guided radiotherapy (IGRT) for head and neck cancer, according to the margins used to expand the clinical target volume (CTV) to create a planning target volume (PTV). METHODS AND MATERIALS: Two-hundred and twenty-five patients were treated with IMRT for squamous cell carcinoma of the head and neck. Daily IGRT scans were acquired using either kilovoltage or megavoltage volumetric imaging prior to each delivered fraction. The first 95 patients were treated with IMRT with 5-mm CTV-to-PTV margins. The subsequent 130 patients were treated using 3-mm PTV expansion margins. RESULTS: Two-year estimates of overall survival, local-regional control, and distant metastasis-free survival were 76%, 78%, and 81%, respectively. There were no differences with respect to any of these endpoints among patients treated with 5-mm and 3-mm PTV expansion margins (p > 0.05, all). The 2-year local-regional control rate for patients treated with IMRT with 5-mm and 3-mm PTV margins was 78% and 78%, respectively (p = 0.96). Spatial evaluation revealed no differences in the incidences of marginal failures among those treated with 5-mm and 3-mm PTV margins. CONCLUSIONS: The use of 3-mm PTV expansion margins appears adequate and did not increase local-regional failures among patients treated with IMRT for head and neck cancer. These data demonstrate the safety of PTV reduction of less than 5 mm and support current protocols recommending this approach in the setting of daily IGRT.
PURPOSE: To compare patterns of disease failure among patients treated with intensity-modulated radiotherapy (IMRT) in conjunction with daily image-guided radiotherapy (IGRT) for head and neck cancer, according to the margins used to expand the clinical target volume (CTV) to create a planning target volume (PTV). METHODS AND MATERIALS: Two-hundred and twenty-five patients were treated with IMRT for squamous cell carcinoma of the head and neck. Daily IGRT scans were acquired using either kilovoltage or megavoltage volumetric imaging prior to each delivered fraction. The first 95 patients were treated with IMRT with 5-mm CTV-to-PTV margins. The subsequent 130 patients were treated using 3-mm PTV expansion margins. RESULTS: Two-year estimates of overall survival, local-regional control, and distant metastasis-free survival were 76%, 78%, and 81%, respectively. There were no differences with respect to any of these endpoints among patients treated with 5-mm and 3-mm PTV expansion margins (p > 0.05, all). The 2-year local-regional control rate for patients treated with IMRT with 5-mm and 3-mm PTV margins was 78% and 78%, respectively (p = 0.96). Spatial evaluation revealed no differences in the incidences of marginal failures among those treated with 5-mm and 3-mm PTV margins. CONCLUSIONS: The use of 3-mm PTV expansion margins appears adequate and did not increase local-regional failures among patients treated with IMRT for head and neck cancer. These data demonstrate the safety of PTV reduction of less than 5 mm and support current protocols recommending this approach in the setting of daily IGRT.
Authors: Adam D Yock; Adam S Garden; Laurence E Court; Beth M Beadle; Lifei Zhang; Lei Dong Journal: Int J Radiat Oncol Biol Phys Date: 2013-07-29 Impact factor: 7.038
Authors: Markus Stoll; Eva Maria Stoiber; Sarah Grimm; Jürgen Debus; Rolf Bendl; Kristina Giske Journal: PLoS One Date: 2016-12-29 Impact factor: 3.240
Authors: Jared D Sturgeon; John A Cox; Lauren L Mayo; G Brandon Gunn; Lifei Zhang; Peter A Balter; Lei Dong; Musaddiq Awan; Esengul Kocak-Uzel; Abdallah Sherif Radwan Mohamed; David I Rosenthal; Clifton David Fuller Journal: Int J Comput Assist Radiol Surg Date: 2014-12-05 Impact factor: 2.924
Authors: C Leitzen; T Wilhelm-Buchstab; S Garbe; C Lütter; T Müdder; B Simon; H H Schild; H Schüller Journal: Strahlenther Onkol Date: 2013-12-11 Impact factor: 3.621