Can the risk of secondary cancer induction after breast conserving therapy be reduced using intraoperative radiotherapy (IORT) with low-energy x-rays?
Open Access
- 16 December 2011
- journal article
- Published by Springer Science and Business Media LLC in Radiation Oncology
- Vol. 6 (1), 174
- https://doi.org/10.1186/1748-717x-6-174
Abstract
Background Radiation induced secondary cancers are a rare but severe late effect after breast conserving therapy. Intraoperative radiotherapy (IORT) is increasingly used during breast conserving surgery. The purpose of this analysis was to estimate secondary cancer risks after IORT compared to other modalities of breast radiotherapy (APBI - accelerated partial breast irradiation, EBRT - external beam radiotherapy). Methods Computer-tomography scans of an anthropomorphic phantom were acquired with an INTRABEAM IORT applicator (diameter 4 cm) in the outer quadrant of the breast and transferred via DICOM to the treatment planning system. Ipsilateral breast, contralateral breast, ipsilateral lung, contralateral lung, spine and heart were contoured. An INTRABEAM source (50 kV) was defined with the tip of the drift tube at the center of the spherical applicator. A dose of 20 Gy at 0 mm depth from the applicator surface was prescribed for IORT and 34 Gy (5 days × 2 × 3.4 Gy) at 10 mm depth for APBI. For EBRT a total dose of 50 Gy in 2 Gy fractions was planned using two tangential fields with wedges. The mean and maximal doses, DVHs and volumes receiving more than 0.1 Gy and 4 Gy of organs at risk (OAR) were calculated and compared. The life time risk for secondary cancers was estimated according to NCRP report 116. Results IORT delivered the lowest maximal doses to contralateral breast (< 0.3 Gy), ipsilateral (1.8 Gy) and contralateral lung (< 0.3 Gy), heart (1 Gy) and spine (< 0.3 Gy). In comparison, maximal doses for APBI were 2-5 times higher. EBRT delivered a maximal dose of 10.4 Gy to the contralateral breast and 53 Gy to the ipsilateral lung. OAR volumes receiving more than 4 Gy were 0% for IORT, < 2% for APBI and up to 10% for EBRT (ipsilateral lung). The estimated risk for secondary cancer in the respective OAR is considerably lower after IORT and/or APBI as compared to EBRT. Conclusions The calculations for maximal doses and volumes of OAR suggest that the risk of secondary cancer induction after IORT is lower than compared to APBI and EBRT.Keywords
This publication has 52 references indexed in Scilit:
- Doses to internal organs for various breast radiation techniques - implications on the risk of secondary cancers and cardiomyopathyRadiation Oncology, 2011
- Exposure to Oral Bisphosphonates and Risk of Esophageal CancerJama-Journal Of The American Medical Association, 2010
- Cyclophosphamide, Epirubicin, and Fluorouracil Versus Dose-Dense Epirubicin and Cyclophosphamide Followed by Paclitaxel Versus Doxorubicin and Cyclophosphamide Followed by Paclitaxel in Node-Positive or High-Risk Node-Negative Breast CancerJournal of Clinical Oncology, 2010
- Second solid cancers after radiotherapy for breast cancer in SEER cancer registriesBritish Journal of Cancer, 2009
- Second malignancies after breast cancer: the impact of different treatment modalitiesBritish Journal of Cancer, 2008
- Risk of Second Malignancies After Adjuvant Radiotherapy for Breast Cancer: A Large-Scale, Single-Institution ReviewInternational Journal of Radiation Oncology*Biology*Physics, 2007
- Late Cardiac Mortality and Morbidity in Early-Stage Breast Cancer Patients After Breast-Conservation TreatmentJournal of Clinical Oncology, 2006
- Assessing the impact of screening mammography: breast cancer incidence and mortality rates in Connecticut (1943–2002)Breast Cancer Research and Treatment, 2006
- Risk of Cardiac Death After Adjuvant Radiotherapy for Breast CancerJNCI Journal of the National Cancer Institute, 2005
- Evidence for curvilinearity in the cancer incidence dose-response in the Japanese atomic bomb survivorsInternational Journal of Radiation Biology, 1996