Article Figures & Data
Tables
Survey questions and response(s) n (%) The following is a reason not to hypofractionate* Nodal irradiation, with or without InM radiation 4 (16.7) DCIS 3 (12.5) Postmastectomy 2 (8.3) InM radiation 6 (25) Immediate reconstruction 11 (45.8) Skin involvement 3 (12.5) None 6 (25) Other 2 (8.3) Dose (Gy/F) 42.4/16 5 (20.8) 40/15 18 (75) Other 1 (4.2) Boost dose (Gy/F) 2.00 12 (50) 2.5 12 (50) Organs at risk constraints I use the exact same constraints as conventional fractionation 13 (54.2) I change the dose parameters based on the EQD2 calculation 6 (25) I follow a certain institutional or trial protocol 5 (20.8) ↵* Multiple responses allowed. InM: internal mammary, DCIS: ductal carcinoma in situ, EQD2: equivalent dose in 2 Gy fraction
Survey questions and response(s) n (%) The following is an indication for PMRT in my practice* T3N0 20 (83.3) T3N1 24 (100) T4N any 24 (100) T1-T2N1 21 (87.5) High-risk node negative 13 (54.2) Other 2 (8.3) PMRT volumes* Chest wall only unless its N+ 14 (58.3) Chest wall and regional nodes always 5 (20.8) Chest wall and regional nodes for any T4 11 (45.8) Chest wall +/- regional nodes for high-risk node negative 9 (37.5) Bolus placement Always, every day, removed only for skin intolerance 2 (8.3) Always, half of the course 14 (58.3) For T4 only, everyday 1 (4.2) For T4 only, half of the course 6 (25) Other 1 (4.2) The following is an indication for scar boost after mastectomy Close or positive margin 13 (54.2) I boost all patients 1 (4.2) None 5 (20.8) ↵* Multiple responses allowed PMRT: postmastectomy radiotherapy. T: tumor, N: node
Survey questions and response(s) n (%) The following is an indication for RNI after BCS and ALND* Any N1 15 (62.5) Macrometastatic N1 14(58.3) N1 with high-risk features 16 (66.7) N1 with inadequate axillary dissection 19 (79.2) N1 with extracapsular extension 18 (75) N2 21 (87.5) Any T3N0 3 (12.5) T3N0 with high-risk features 11 (45.8) T2N0 with high-risk features 4 (16.7) Nx 10 (41.7) The following is an indication for RNI after MRM* Any N1 13 (54.2) Macrometastatic N1 13 (54.2) N1 with high-risk features 14 (58.3) N1 with inadequate axillary dissection 18 (75) N1 with extracapsular extension 17 (70.8) N2 21 (87.5) Any T3N0 5 (20.8) T3N0 with high-risk features 15 (62.5) T2N0 with high-risk features 2 (8.3) Nx 8 (33.3) The following is an indication for InM LN radiation* Radiologically positive InM node 23 (95.8) N1 and medially located tumor 14 (58.3) N0 and medially located tumor with certain high-risk features 3 (12.5) When 50% or more of the axilla is positive 14 (58.3) Whenever RNI is indicated for right-sided tumors only 1 (4.2) Whenever RNI is indicated 2 (8.3) The definition of adequate LN dissection is 8 or more 3 (12.5) 10 or more 20 (83.3) 15 or more 1 (4.2) ↵* Multiple responses allowed, CTV: clinical target volume, IMRT: intensity modulated radiotherapy, LN: lymph node, RTOG: Radiation Therapy Oncology Group, PTV: planning target volume, ESTRO: European Society for Radiotherapy and Oncology, InM; internal mammary, VMAT: volumetric modulated arc therapy, SC: supraclavicular, ECE: extracapsular extension, T: tumor, N: node
Survey question Response n (%) I contour chest wall/breast Always 21 (87.5) Never 1 (4.2) Only when treating with IMRT 2 (8.3) I contour nodal CTV Always 23 (95.8) Never 0 (0) Only when treating with IMRT 1 (4.2) If nodal CTV was contoured* I adjust the field border/shielding accordingly 16 (66.7) I follow the standard field borders and use the contours for reference only 9 (37.5) I don’t contour nodal CTV anyway 0 (0) Other 0 (0) My LN CTV follows RTOG atlas 20 (83.3) ESTRO atlas 2 (8.3) Other 2 (8.3) My LN PTV Is 3 mm 3 (12.5) Is 5 mm 12 (50) Is equal to my CTV 2 (8.3) Is technique dependent, I add 3-5 mm when using IMRT but not with 3D 7 (29.2) Other 0.(0) InM PTV Is equal to my CTV 2 (8.3) 5 mm all around 5 (20.8) 3 mm all around 3 (12.5) 3 or 5 mm, but trimmed from lung/heart 6 (25) Is technique dependent, I add 3-5 mm when using IMRT but not with 3D, and I DO NOT trim from lung or heart 5 (20.8) Is technique dependent, I add 3-5 mm when using IMRT but not with 3D, and I DO trim from lung or heart 3 (12.5) Other 0 (0) Acceptable InM PTV coverage is 80% of prescription 7 (29.2) 90% of prescription 8 (33.3) 95% of prescription 4 (16.7) I only care about CTV coverage 4 (16.7) Acceptable InM CTV coverage 80% of prescription 6 (25) 90% of prescription 13 (54.2) 95% of prescription 5 (20.8) Technique used when treating InM* Modified wide tangents whenever possible 21 (87.5) Direct electron field matching photon tangents whenever possible 4 (16.7) Step and shoot IMRT 6 (25) VMAT 13 (54.2) Tomotherapy 4 (16.7) Other 0 (0) RNI after axillary dissection* For any N1 I treat as per MA20 (small SC field encompassing axilla 3-SC) 16 (66.7) For N1+ ECE I treat the full axilla+SC+/-InM 14 (58.3) For any N1 I treat the full axilla+SC+/-InM 2 (8.3) For N1+ inadequate dissection I treat the full axilla+SC+/-InM 17 (70.8) For N2 I always treat the dissected axilla +SC+/- InM (large MA20 SC field) 13 (54.2) For N2 I treat the dissected axilla only in cases of inadequate dissection or extensive nodal involvement 10 (41.7) ↵* Multiple responses allowed. CTV: clinical target volume, IMRT: intensity modulated radiotherapy, LN: lymph node, RTOG: Radiation Therapy Oncology Group, PTV: planning target volume, ESTRO: European Society for Radiotherapy and Oncology, InM: internal mammary, VMAT: volumetric modulated arc therapy, RNI: regional nodal irradiation, SC: supraclavicular, ECE: extracapsular extension
Survey questions and response(s) n (%) I use DIBH technique(s) With 3D 11(45) With IMRT/VMAT 1 (4.2) With both 5 (20.8) I do not use it 7 (29.2) I use DIBH technique(s)* For all left-sided patients 10 (41.7) When treating InM on the left side 8 (33.3) When heart constraints are not acceptable 11(45.8) At our department we have a protocol for screening patients who could benefit from it 2 (8.3) I do not use it because it is not available at our center 6 (25) Other 1 (4.2) If you chose other above, please specify Any side with InMN, also if liver is located high in chest and occasionally with right side SCV field if very young patient I do not use DIBH technique(s) because* The accessories are not available at my center, I would love to acquire them 7 (53.8) It takes a long time in the machine; we cannot afford it 3 (23.1) I am satisfied with my treatment without it 5 (38.5) No reason, just never thought of using it 1 (7.7) ↵* Multiple responses allowed. DIBH: deep inspirational breath hold, IMRT: intensity modulated radiotherapy, VMAT: volumetric modulated arc therapy, InM: internal mammary, InMN: internal mammary nodes, SCV: supraclavicular