Second cancer risk after 3D-CRT, IMRT and VMAT for breast cancer.

Abstract

PURPOSE:

Second cancer risk after breast conserving therapy is becoming more important due to improved long term survival rates. In this study, we estimate the risks for developing a solid second cancer after radiotherapy of breast cancer using the concept of organ equivalent dose (OED).

MATERIALS AND METHODS:

Computer-tomography scans of 10 representative breast cancer patients were selected for this study. Three-dimensional conformal radiotherapy (3D-CRT), tangential intensity modulated radiotherapy (t-IMRT), multibeam intensity modulated radiotherapy (m-IMRT), and volumetric modulated arc therapy (VMAT) were planned to deliver a total dose of 50 Gy in 2 Gy fractions. Differential dose volume histograms (dDVHs) were created and the OEDs calculated. Second cancer risks of ipsilateral, contralateral lung and contralateral breast cancer were estimated using linear, linear-exponential and plateau models for second cancer risk.

RESULTS:

Compared to 3D-CRT, cumulative excess absolute risks (EAR) for t-IMRT, m-IMRT and VMAT were increased by 2 ± 15%, 131 ± 85%, 123 ± 66% for the linear-exponential risk model, 9 ± 22%, 82 ± 96%, 71 ± 82% for the linear and 3 ± 14%, 123 ± 78%, 113 ± 61% for the plateau model, respectively.

CONCLUSION:

Second cancer risk after 3D-CRT or t-IMRT is lower than for m-IMRT or VMAT by about 34% for the linear model and 50% for the linear-exponential and plateau models, respectively.

• Authors: Yasser Abo-Madyan, Muhammad Hammad Aziz, Moamen M O M Aly, Frank Schneider, Elena Sperk, Sven Clausen, Frank A Giordano, Carsten Herskind, Volker Steil, Frederik Wenz, Gerhard Glatting
• Journal: Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology (Radiother Oncol) Vol. 110 Issue 3 Pg. 471-6 (Mar 2014) ISSN: 1879-0887 [Electronic] Ireland
• PMID: 24444525 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Topics

• Aged
• Breast Neoplasms (radiotherapy)
• Female
• Humans
• Middle Aged
• Neoplasms, Radiation-Induced
• Neoplasms, Second Primary (etiology)
• Radiotherapy Dosage
• Radiotherapy Planning, Computer-Assisted (methods)
• Radiotherapy, Conformal (adverse effects)
• Radiotherapy, Intensity-Modulated (adverse effects)
• Risk