Original Research Article
Year: 2019 | Month: October | Volume: 6 | Issue: 10 | Pages: 315-320
To Evaluate and Compare the Dosimetric Effects of Deep Inspiratory Breath-Hold Technique with Free Breathing Technique With Respect To Target Coverage and Organs at Risk in Patients of Left Sided Breast Cancer Treated By External Beam Radiotherapy
Pandita Sumit1, Sharma Manish2, Mandal Avik2, Patel Arvind3
1DNB Radiation Oncology, Junior Consultant Radiation Oncology, Batra Hospital and Medical Research Centre, New Delhi.
2DNB Radiation Oncology, Senior Resident Radiation Oncology, Batra Hospital and Medical Research Centre, New Delhi.
3M.Sc Physics, Physicist, Batra Hospital and Medical Research Centre, New Delhi.
Corresponding Author: Pandita Sumit
ABSTRACT
Context: Radiotherapy techniques in breast cancer treatment have improved over years but have also raised concerns over subsequent acute and late effects. One such late complication, cardiac toxicity has led to much interest and optimisation in treatment delivery.
Aims: The aim of this study was to compare dose received by the target and organs at risk in left sided breast cancer patients undergoing post-operative radiotherapy with Deep Inspiratory Breath Hold (DIBH) technique and to compare its results with Conventional Free Breathing (FB) technique.
Materials and Methods: 24 patients of left-sided breast cancer requiring post-operative were taken for study after proper breath-hold training. CT-simulation was done in both free breathing and deep inspiration breath-hold pattern. The treatment plans were generated for both FB and DIBH. Dosimetric values were recorded and compared for both the plans.
Design of Study: A Prospective Observational Study.
Statistical analysis used: Statistical analysis was done using IBM SPSS statistical software version 16.0. Paired t-tests were used for statistical analysis of the differences.
Results: In our study, DIBH plans resulted in significant reduction in heart doses including Dmean (4.84 vs 3.93 Gy), V5 (19.33 vs 16.23), V10 (16.33 vs 13.59), V20 (13.87 vs 12.07), V30 (10.88 vs 9.90) and V40 (0.67 vs 0.41). DIBH also resulted in a significant reduction in all the LAD parameters including Dmax (45.26 vs 43.55 Gy), Dmean (25.54 vs 23.91 Gy), V5 (65.53 vs 59.06), V10 (52.51 vs 40.11), V20 (40.79 vs 28.16), V30 (28.05 vs 16.24) and V40 (14.95 vs 5.24). For LAD maximum relative reduction was observed for V40 (64.9%) and the minimum relative reduction was for Dmax. Compared with FB, DIBH resulted in a significant reduction in lung dose parameters including Dmean (3.85 vs 2.69 Gy), V20 (5.92 vs 3.54) and V40 (2.97 vs 1.61).
Conclusion: In our study dosimetric comparison between FB and DIBH plans showed significantly lower doses to heart, lung and LAD without compromising target coverage. Further prospective studies with longer follow-up are required to evaluate the cardiac and pulmonary toxicity.
Keywords: Deep inspiratory breath-hold (DIBH), Maximum heart distance (MHD), Central lung distance (CLD).
[PDF Full Text]