TURKISH JOURNAL OF ONCOLOGY 2020 , Vol 35 , Num 4
Contribution of Deep Inspiration Breath-Hold Technique for Regional Nodal Irradiation Including Mammaria Interna in Mastectomized Left-Sided Breast Cancer Patients
Meltem DAĞDELEN1,Şefika Arzu ERGEN1,Servet İPEK1,Ceren BARLAS1,Songül ÇAVDAR KARAÇAM1,Didem ÇOLPAN ÖKSÜZ1
1Department of Radiation Oncology, İstanbul University Cerrahpaşa-Cerrahpaşa Medical Faculty, Istanbul-Turkey DOI : 10.5505/tjo.2020.2343 OBJECTIVE
This study aim to investigate the feasibility and the cardiac and lung-sparing value of Deep Inspiration Breath-Hold (DIBH) technique compared to the Free Breathing (FB) technique among left-sided breast cancer patients who underwent chest-wall, level 3±level 1-2 axillary, supraclavicular and the internal mammary nodes (IMN) irradiation.

METHODS
Ten patients who underwent the modified radical mastectomy and were treated with adjuvant radiotherapy were included in this study. All patients underwent CT simulation during FB and DIBH. Audiovisual guidance was used. Target volumes included chest-wall and regional nodes. The treatment plans and dose-volume histograms that were created on both CT scans were used to compare doses to heart, ventricle, left anterior descending artery (LAD) and lung.

RESULTS
The mean heart dose was reduced from 6,4 Gy to 3,3 Gy using DIBH technique. Heart V20, V30 and V40 and maximum dose were significantly decreased in the DIBH plans compared to FB. For LAD coronary artery, there was a significant reduction in mean dose from 42,5 Gy to 20,5 Gy in DIBH plans. There was a significant reduction in mean dose to the ipsilateral lung (ilung); V5, V10, V20 in DIBH plans.

CONCLUSION
Patients with locally advanced left-sided breast cancer require additional attention to improve heart and lung sparing to reduce late cardiovascular events and secondary cancer risks. DIBH technique led to significant reductions in heart, ventricle, LAD, left lung DVH parameters without compromising the dose coverage to PTV in patients treated with chest-wall and lymphatic irradiation, including IMN. Keywords : Breast cancer; chest wall irradiation; deep inspiration breath hold; free breath; lymphatic radiotherapy