PURPOSE: At present, radiation (RT) fields are based largely, and often solely, on bony anatomy. Recent efforts have been taken to better define lymphatic regions for RT planning. Lymphotrophic nanoparticle-enhanced MRI (LN-MRI) allows for accurate identification of malignant and benign lymph nodes. We sought to evaluate RT delivery to lymphatics for breast cancer using LN-MRI. METHODS AND MATERIALS: Twenty-three patients with breast cancer underwent LN-MRI. MRIs were anatomically registered to a reference CT; benign and malignant lymph nodes were contoured. Standard RT fields were planned and dose calculated to prescribe 45-50 Gy. Lymphatic regions were contoured on CT. Coverage of LN-MRI lymph nodes by RT fields and contoured lymphatics were assessed. RESULTS: Eighty-one percent of all lymph nodes defined by LN-MRI were covered by the 45-Gy isodose line; 82% of malignant and 79% of benign. The 50-Gy isodose line only encompassed 60% of LN-MRI defined lymph nodes-64% of malignant and 59% of benign. For nodal volumes contoured in the absence of a margin, 86% of actual lymph nodes were within contoured volumes. When a 5-mm expansion was added, 99% were included. CONCLUSIONS: LN-MRI is a useful tool to delineate the location of breast regional lymphatics. These results suggest less than desired coverage of lymph nodes using standard RT fields and that a margin may be advisable when defining nodal volumes by CT. The use of IMRT and RT in lieu of surgery makes accurate definition of the location of breast regional lymphatics of paramount importance. Published by Elsevier Inc.
PURPOSE: At present, radiation (RT) fields are based largely, and often solely, on bony anatomy. Recent efforts have been taken to better define lymphatic regions for RT planning. Lymphotrophic nanoparticle-enhanced MRI (LN-MRI) allows for accurate identification of malignant and benign lymph nodes. We sought to evaluate RT delivery to lymphatics for breast cancer using LN-MRI. METHODS AND MATERIALS: Twenty-three patients with breast cancer underwent LN-MRI. MRIs were anatomically registered to a reference CT; benign and malignant lymph nodes were contoured. Standard RT fields were planned and dose calculated to prescribe 45-50 Gy. Lymphatic regions were contoured on CT. Coverage of LN-MRI lymph nodes by RT fields and contoured lymphatics were assessed. RESULTS: Eighty-one percent of all lymph nodes defined by LN-MRI were covered by the 45-Gy isodose line; 82% of malignant and 79% of benign. The 50-Gy isodose line only encompassed 60% of LN-MRI defined lymph nodes-64% of malignant and 59% of benign. For nodal volumes contoured in the absence of a margin, 86% of actual lymph nodes were within contoured volumes. When a 5-mm expansion was added, 99% were included. CONCLUSIONS: LN-MRI is a useful tool to delineate the location of breast regional lymphatics. These results suggest less than desired coverage of lymph nodes using standard RT fields and that a margin may be advisable when defining nodal volumes by CT. The use of IMRT and RT in lieu of surgery makes accurate definition of the location of breast regional lymphatics of paramount importance. Published by Elsevier Inc.
Authors: Tristan C F van Heijst; Bram van Asselen; Ruud M Pijnappel; Marissa Cloos-van Balen; Jan J W Lagendijk; Desirée van den Bongard; Mariëlle E P Philippens Journal: Br J Radiol Date: 2016-05-10 Impact factor: 3.039
Authors: Marc D Normandin; Hushan Yuan; Moses Q Wilks; Howard H Chen; Joseph M Kinsella; Hoonsung Cho; Nicolas J Guehl; Nader Absi-Halabi; Seyed Mohammadreza Hosseini; Georges El Fakhri; David E Sosnovik; Lee Josephson Journal: Angew Chem Int Ed Engl Date: 2015-09-14 Impact factor: 15.336
Authors: Robert W Mutter; J Isabelle Choi; Rachel B Jimenez; Youlia M Kirova; Marcio Fagundes; Bruce G Haffty; Richard A Amos; Julie A Bradley; Peter Y Chen; Xuanfeng Ding; Antoinette M Carr; Leslie M Taylor; Mark Pankuch; Raymond B Mailhot Vega; Alice Y Ho; Petra Witt Nyström; Lisa A McGee; James J Urbanic; Oren Cahlon; John H Maduro; Shannon M MacDonald Journal: Int J Radiat Oncol Biol Phys Date: 2021-05-25 Impact factor: 8.013