BACKGROUND: Oropharynx cancers treated with intensity-modulated radiation (IMRT) are often treated with a monoisocentric or half-beam technique (HB). IMRT is delivered to the primary tumor and upper neck alone, while the lower neck is treated with a matching anterior beam. Because IMRT can treat the entire volume or whole field (WF), the primary aim of the study was to test the ability to plan cases using WF-IMRT while obtaining an optimal plan and acceptable dose distribution and also respecting normal critical structures. METHODS AND MATERIALS: Thirteen patients with early-stage oropharynx cancers had treatment plans created with HB-IMRT and WF-IMRT techniques. Plans were deemed acceptable if they met the planning guidelines (as defined or with minor violations) of the Radiation Therapy Oncology Group protocol H0022. Comparisons included coverage to the planning target volume (PTV) of the primary (PTV66) and subclinical disease (PTV54). We also compared the ability of both techniques to respect the tolerance of critical structures. RESULTS: The volume of PTV66 treated to >110% was less in 9 of the 13 patients in the WF-IMRT plan as compared to the HB-IMRT plan. The calculated mean volume receiving >110% for all patients planned with WF-IMRT was 9.3% (0.8%-25%) compared to 13.7% (2.7%-23.7%) with HB-IMRT (p = 0.09). The PTV54 volume receiving >110% of dose was less in 10 of the 13 patients planned with WF-IMRT compared to HB-IMRT. The mean doses to all critical structures except the larynx were comparable with each plan. The mean dose to the larynx was significantly less (p = 0.001), 18.7 Gy, with HB-IMRT compared to 47 Gy with WF-IMRT. CONCLUSIONS: Regarding target volumes, acceptable plans can be generated with either WF-IMRT or HB-IMRT. WF-IMRT has an advantage if uncertainty at the match line is a concern, whereas HB-IMRT, particularly in cases not involving the base of tongue, can achieve much lower doses to the larynx.
BACKGROUND: Oropharynx cancers treated with intensity-modulated radiation (IMRT) are often treated with a monoisocentric or half-beam technique (HB). IMRT is delivered to the primary tumor and upper neck alone, while the lower neck is treated with a matching anterior beam. Because IMRT can treat the entire volume or whole field (WF), the primary aim of the study was to test the ability to plan cases using WF-IMRT while obtaining an optimal plan and acceptable dose distribution and also respecting normal critical structures. METHODS AND MATERIALS: Thirteen patients with early-stage oropharynx cancers had treatment plans created with HB-IMRT and WF-IMRT techniques. Plans were deemed acceptable if they met the planning guidelines (as defined or with minor violations) of the Radiation Therapy Oncology Group protocol H0022. Comparisons included coverage to the planning target volume (PTV) of the primary (PTV66) and subclinical disease (PTV54). We also compared the ability of both techniques to respect the tolerance of critical structures. RESULTS: The volume of PTV66 treated to >110% was less in 9 of the 13 patients in the WF-IMRT plan as compared to the HB-IMRT plan. The calculated mean volume receiving >110% for all patients planned with WF-IMRT was 9.3% (0.8%-25%) compared to 13.7% (2.7%-23.7%) with HB-IMRT (p = 0.09). The PTV54 volume receiving >110% of dose was less in 10 of the 13 patients planned with WF-IMRT compared to HB-IMRT. The mean doses to all critical structures except the larynx were comparable with each plan. The mean dose to the larynx was significantly less (p = 0.001), 18.7 Gy, with HB-IMRT compared to 47 Gy with WF-IMRT. CONCLUSIONS: Regarding target volumes, acceptable plans can be generated with either WF-IMRT or HB-IMRT. WF-IMRT has an advantage if uncertainty at the match line is a concern, whereas HB-IMRT, particularly in cases not involving the base of tongue, can achieve much lower doses to the larynx.
Authors: David L Schwartz; Katherine Hutcheson; Denise Barringer; Susan L Tucker; Merrill Kies; F Christopher Holsinger; K Kian Ang; William H Morrison; David I Rosenthal; Adam S Garden; Lei Dong; Jan S Lewin Journal: Int J Radiat Oncol Biol Phys Date: 2010-06-18 Impact factor: 7.038
Authors: Benjamin J Moeller; Vishal Rana; Blake A Cannon; Michelle D Williams; Erich M Sturgis; Lawrence E Ginsberg; Homer A Macapinlac; J Jack Lee; K Kian Ang; K S Clifford Chao; Gregory M Chronowski; Steven J Frank; William H Morrison; David I Rosenthal; Randal S Weber; Adam S Garden; Scott M Lippman; David L Schwartz Journal: Int J Radiat Oncol Biol Phys Date: 2010-02-18 Impact factor: 7.038
Authors: Aruna Turaka; Tianyu Li; Nicos Nicolaou; Miriam N Lango; Barbara Burtness; Eric M Horwitz; John A Ridge; Steven J Feigenberg Journal: Int J Radiat Oncol Biol Phys Date: 2010-04-10 Impact factor: 7.038
Authors: Benjamin J Moeller; John S Yordy; Michelle D Williams; Uma Giri; Uma Raju; David P Molkentine; Lauren A Byers; John V Heymach; Michael D Story; J Jack Lee; Erich M Sturgis; Randal S Weber; Adam S Garden; K Kian Ang; David L Schwartz Journal: Clin Cancer Res Date: 2011-02-24 Impact factor: 12.531
Authors: Adam S Garden; William H Morrison; Pei-Fong Wong; Sam S Tung; David I Rosenthal; Lei Dong; Brian Mason; George H Perkins; K Kian Ang Journal: Int J Radiat Oncol Biol Phys Date: 2006-12-04 Impact factor: 7.038
Authors: N Patrik Brodin; Rafi Kabarriti; Mark Pankuch; Clyde B Schechter; Vinai Gondi; Shalom Kalnicki; Chandan Guha; Madhur K Garg; Wolfgang A Tomé Journal: Int J Radiat Oncol Biol Phys Date: 2018-11-26 Impact factor: 7.038