Page | 339 The effect of a breath-hold technique on conformal and intensity- modulated radiotherapy techniques at right-sided breast cancer radiotherapy including internal mammarian fields How to cite: Yücel S, Dişçi E, Güral Z, Oskeroğlu S, Kadıoğlu H, Ağaoğlu F. The effect of breath-hold technique on conformal and intensity modulated radiotherapy techniques at right-sided breast cancer radiotherapy including internal mammarian field. J Surg Med. 2023;7(5):339-342. J Surg Med. 2023;7(5):339-342. Research article DOI: 10.28982/josam.7695 Serap Yücel 1 , Erhan Dişçi 2 , Zeynep Güral 1 , Sedenay Oskeroğlu 3 , Hüseyin Kadıoğlu 4 , Fulya Ağaoğlu 1 1 Department of Radiation Oncology, School of Medicine, Acıbadem University, Istanbul, Turkey 2 Department of Radiation Oncology, Acıbadem Atakent Hospital, Istanbul, Turkey 3 Department of Radiation Oncology, Acıbadem Atasehir Hospital, Istanbul, Turkey 4 Department of General Surgery, Yeniyuzyil University, Istanbul, Turkey ORCID ID of the author(s) SY: 0000-0003-4948-8927 ED: 0000-0002-7857-5045 ZG: 0000-0003-3968-8255 SO: 0000-0001-7295-3722 HK: 0000-0003-1953-4400 FA: 0000-0002-4868-9543 Corresponding Author Serap Yucel Acibadem Atakent Hospital, Kucukcekmece, Istanbul, Turkey E-mail: serapbaskaya@yahoo.com  Ethics Committee Approval The study does not require any ethical permissions since it is a dosimetric study.  Conflict of Interest No conflict of interest was declared by the authors.  Financial Disclosure The authors declared that this study has received no financial support.  Published 2023 May 23 Copyright © 2023 The Author(s) Published by JOSAM This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND 4.0) where it is permissible to download, share, remix, transform, and buildup the work provided it is properly cited. The work cannot be used commercially without permission from the journal. Abstract Background/Aim: Significantly lower heart doses can be achieved by breath-hold technique at left-sided breast cancer radiotherapy (RT). We see high doses at organs at risk such as lung, heart, and contralateral breast during right-sided breast cancer RT planning especially in the presence of RT indication for mammaria interna (MI) lymph nodes. This study compared RT-planning methods that are conformal with intensity-modulated RT (IMRT) with breath holding and free breathing for right-sided breast cancer RT including full axillary and MI lymph node fields. Methods: Computed tomography (CT) simulations were performed using free-breath (FB) and breath-hold (BH) methods in 10 patients with right-sided breast cancer. A total of 40 RT treatment plans were calculated. Right-sided breast, level 1-2-3 axillary regions, and MI regions served for the target-planning volume. Left-sided breast, heart, as well as right-sided and left lungs were contoured as critical organs according to the atlas of the "Radiation Therapy Oncology Group." We used a Varian Eclipse v.13 for treatment planning. Conformal “FieldinField” RT (FinFRT) and dynamic IMRT (dIMRT) planning were performed separately for each patient over breath-hold and free-breath images. For PTV, 50 Gy was prescribed in 25 fractions and optimized such that the planned target volume (PTV) remained between 95% and 110% of the dose. The mean and maximum doses of the heart, V5 and V20 of the lungs, as well as V95 doses for MI were recorded. Statistical analyses were performed with SPSS version 22, and a paired t-test was used for comparison. Results: Four treatment plans (FB FinFRT, BH FinFRT, FB dIMRT, BH dIMRT) were made separately for 10 patients. For comparison, common FB FinFRT plans were accepted as the baseline plan. As expected, there were no significant differences in PTV coverage. The mean dose received by 95% of the MI volume was between 42.27 Gy and 42.4 Gy. For the maximum heart dose, the breath hold technique had no significant effect on plans. The lowest average maximum heart dose was seen in the BH FinFRT group. Mean heart doses are between 1.28 Gy – 4.85 Gy. There was no significance between BH FinFRT and FB FinFRT plan (P=0.504), and there was a significant difference for heart mean dose versus dIMRT plans (P=0.001). The mean V20 of the lungs ranged from 11.9 to 17.8. There was a significant decrease in V20 with BH or FB dIMRT plans (P=0.001). There was no difference between BH FinFRT (P=0.138). On the contrary, lung V5 values were significantly higher in dIMRT plans, and the lowest mean V5 value was seen in BH FinFRT plan. Conclusion: With the BH method, lower doses (but not significantly lower doses) were obtained in critical organ doses. There was a significant decrease with FinFRT plans in terms of heart mean and maximum dose and lung V5 percentages. The dIMRT plans were significant only in lung V20 percentages. When planning RT, we recommend evaluating all treatment techniques individually for right-sided breast cancer patients to obtain lower doses in critical organs. Keywords: breath-hold, radiotherapy, internal mammarian field, breast cancer