South Asian Journal of Cancer

ORIGINAL ARTICLE: BREAST CANCER
Year
: 2018  |  Volume : 7  |  Issue : 3  |  Page : 163--166

Breast-conserving radiotherapy with simultaneous integrated boost; field-in-field three-dimensional conformal radiotherapy versus inverse intensity-modulated radiotherapy – A dosimetric comparison: Do we need intensity-modulated radiotherapy?


Bindhu Joseph, Nisma Farooq, Sabari Kumar, CR Vijay, Kurian J Puthur, C Ramesh, Vishwanath Lokesh 
 Department of Radiotherapy, Kidwai Memorial Institute of Oncology, Bengaluru, Karnataka, India

Correspondence Address:
Dr. Bindhu Joseph
Department of Radiotherapy, Kidwai Memorial Institute of Oncology, Bengaluru, Karnataka
India

Background and Purpose: To examine the feasibility of improving breast-conserving radiotherapy with simultaneous integrated boost (SIB) and analyzing the efficiency of forward versus inverse intensity-modulated radiotherapy (IMRT) techniques in providing the same. Materials and Methods: Three-dimensional conformal radiotherapy (3DCRT) field-in-field (FIF) plans with simultaneous and sequential boost and IMRT SIB plans were generated for the datasets of 20 patients who had undergone breast-conserving surgery. The 3 plans were compared dosimetrically for efficiency in terms of planning target volume (PTV) coverage (PTV 95%), homogeneity and conformity, dose delivered to ipsilateral/contralateral lungs (I/L: V10, V20, C/L: Vmean, V5), heart and contralateral breast (Vmean, V30 for heart and Vmean, V1, V5 for C/L breast). Results: The FIF 3DCRT plan with SIB (PLAN B) was more homogeneous than the classical technique with sequential boost (PLAN A). There were less hot spots in terms of Dmax (63.7 ± 1.3) versus Dmax (68.9 ± 1), P < 0.001 and boost V107%, B (0.3 ± 0.7) versus A (3.5 ± 5.99), P = 0.001. The IMRT SIB (PLAN C) did not provide any significant dosimetric advantage over the 3DCRT SIB technique. IMRT SIB plan C was associated with increased dose to contralateral lung in-terms of V5 (10.35 +/- 18.23) vs. (1.13 +/- 4.24), P = 0.04 and Vmean (2.12 ± 2.18) versus Vmean (0.595 ± 0.89), P = 0.008. There was 3-fold greater exposure in terms of Monitor Unit (MU) (1024.9 ± 298.32 versus 281.05 ± 20.23, P < 0.001) and treatment delivery time. Conclusions: FIF 3DCRT SIB provides a dosimetrically acceptable and technically feasible alternative to the classical 3DCRT plan with sequential boost for breast-conserving radiotherapy. It reduces treatment time by 2 weeks. IMRT SIB does not appear to have any dosimetric advantage; it is associated with significantly higher doses to contralateral lung and heart and radiation exposure in terms of MU.


How to cite this article:
Joseph B, Farooq N, Kumar S, Vijay C R, Puthur KJ, Ramesh C, Lokesh V. Breast-conserving radiotherapy with simultaneous integrated boost; field-in-field three-dimensional conformal radiotherapy versus inverse intensity-modulated radiotherapy – A dosimetric comparison: Do we need intensity-modulated radiotherapy?.South Asian J Cancer 2018;7:163-166


How to cite this URL:
Joseph B, Farooq N, Kumar S, Vijay C R, Puthur KJ, Ramesh C, Lokesh V. Breast-conserving radiotherapy with simultaneous integrated boost; field-in-field three-dimensional conformal radiotherapy versus inverse intensity-modulated radiotherapy – A dosimetric comparison: Do we need intensity-modulated radiotherapy?. South Asian J Cancer [serial online] 2018 [cited 2018 Dec 18 ];7:163-166
Available from: http://journal.sajc.org/article.asp?issn=2278-330X;year=2018;volume=7;issue=3;spage=163;epage=166;aulast=Joseph;type=0