PURPOSE: To develop an automated beam placement technique for whole breast radiotherapy using tangential beams. We seek to find optimal parameters for tangential beams to cover the whole ipsilateral breast (WB) and minimize the dose to the organs at risk (OARs). METHODS: A support vector machine (SVM) based method is proposed to determine the optimal posterior plane of the tangential beams. Relative significances of including/avoiding the volumes of interests are incorporated into the cost function of the SVM. After finding the optimal 3-D plane that separates the whole breast (WB) and the included clinical target volumes (CTVs) from the OARs, the gantry angle, collimator angle, and posterior jaw size of the tangential beams are derived from the separating plane equation. Dosimetric measures of the treatment plans determined by the automated method are compared with those obtained by applying manual beam placement by the physicians. The method can be further extended to use multileaf collimator (MLC) blocking by optimizing posterior MLC positions. RESULTS: The plans for 36 patients (23 prone- and 13 supine-treated) with left breast cancer were analyzed. Our algorithm reduced the volume of the heart that receives >500 cGy dose (V5) from 2.7 to 1.7 cm(3) (p = 0.058) on average and the volume of the ipsilateral lung that receives >1000 cGy dose (V10) from 55.2 to 40.7 cm(3) (p = 0.0013). The dose coverage as measured by volume receiving >95% of the prescription dose (V95%) of the WB without a 5 mm superficial layer decreases by only 0.74% (p = 0.0002) and the V95% for the tumor bed with 1.5 cm margin remains unchanged. CONCLUSIONS: This study has demonstrated the feasibility of using a SVM-based algorithm to determine optimal beam placement without a physician's intervention. The proposed method reduced the dose to OARs, especially for supine treated patients, without any relevant degradation of dose homogeneity and coverage in general.
PURPOSE: To develop an automated beam placement technique for whole breast radiotherapy using tangential beams. We seek to find optimal parameters for tangential beams to cover the whole ipsilateral breast (WB) and minimize the dose to the organs at risk (OARs). METHODS: A support vector machine (SVM) based method is proposed to determine the optimal posterior plane of the tangential beams. Relative significances of including/avoiding the volumes of interests are incorporated into the cost function of the SVM. After finding the optimal 3-D plane that separates the whole breast (WB) and the included clinical target volumes (CTVs) from the OARs, the gantry angle, collimator angle, and posterior jaw size of the tangential beams are derived from the separating plane equation. Dosimetric measures of the treatment plans determined by the automated method are compared with those obtained by applying manual beam placement by the physicians. The method can be further extended to use multileaf collimator (MLC) blocking by optimizing posterior MLC positions. RESULTS: The plans for 36 patients (23 prone- and 13 supine-treated) with left breast cancer were analyzed. Our algorithm reduced the volume of the heart that receives >500 cGy dose (V5) from 2.7 to 1.7 cm(3) (p = 0.058) on average and the volume of the ipsilateral lung that receives >1000 cGy dose (V10) from 55.2 to 40.7 cm(3) (p = 0.0013). The dose coverage as measured by volume receiving >95% of the prescription dose (V95%) of the WB without a 5 mm superficial layer decreases by only 0.74% (p = 0.0002) and the V95% for the tumor bed with 1.5 cm margin remains unchanged. CONCLUSIONS: This study has demonstrated the feasibility of using a SVM-based algorithm to determine optimal beam placement without a physician's intervention. The proposed method reduced the dose to OARs, especially for supine treated patients, without any relevant degradation of dose homogeneity and coverage in general.
Authors: David R Soto-Pantoja; Masaki Terabe; Arunima Ghosh; Lisa A Ridnour; William G DeGraff; David A Wink; Jay A Berzofsky; David D Roberts Journal: Cancer Res Date: 2014-10-08 Impact factor: 12.701
Authors: Kelly Kisling; Lifei Zhang; Simona F Shaitelman; David Anderson; Tselane Thebe; Jinzhong Yang; Peter A Balter; Rebecca M Howell; Anuja Jhingran; Kathleen Schmeler; Hannah Simonds; Monique du Toit; Christoph Trauernicht; Hester Burger; Kobus Botha; Nanette Joubert; Beth M Beadle; Laurence Court Journal: Med Phys Date: 2019-07-09 Impact factor: 4.071
Authors: Roberta Castriconi; Pier Giorgio Esposito; Alessia Tudda; Paola Mangili; Sara Broggi; Andrei Fodor; Chiara L Deantoni; Barbara Longobardi; Marcella Pasetti; Lucia Perna; Antonella Del Vecchio; Nadia Gisella Di Muzio; Claudio Fiorino Journal: Front Oncol Date: 2021-08-24 Impact factor: 6.244
Authors: Nienke Bakx; Hanneke Bluemink; Els Hagelaar; Jorien van der Leer; Maurice van der Sangen; Jacqueline Theuws; Coen Hurkmans Journal: Phys Imaging Radiat Oncol Date: 2021-04-28