Comparison of radiation dose to the left anterior descending artery by whole and partial breast irradiation in breast cancer patients

Abstract

PurposeBreast conserving surgery (BCS) followed by whole breast irradiation (WBI) is the standard of care for breast cancer patients. However, there is a risk of coronary events with WBI therapy. In this study, we compared the radiation dose in the left anterior descending artery (LAD) in patients receiving partial breast irradiation (PBI) with WBI.Material and methodsWe evaluated consecutive patients who underwent adjuvant radiotherapy after BCS between October 2008 and July 2014. Whole breast irradiation patients received 50 Gy in fractions of 2 Gy to the entire breast. Partial breast irradiation was performed using multicatheter brachytherapy at a dose of 32 Gy in eight fractions. The mean and maximal cumulative doses to LAD were calculated. The radiotherapeutic biologically effective dose of PBI was adjusted to WBI, and radiation techniques were compared.ResultsOf 379 consecutive patients with 383 lesions receiving radiotherapy (151 WBI and 232 PBI lesions), 82 WBI and 100 PBI patients were analyzed. In WBI patients, the mean and maximal cumulative doses for left-sided breast cancer (2.13 ± 0.11 and 8.19 ± 1.21 Gy, respectively) were significantly higher than those for right-sided (0.37 ± 0.02 and 0.56 ± 0.03 Gy, respectively; p < 0.0001). In PBI patients with left-sided breast cancer, the doses for tumors in inner quadrants or central location (2.54 ± 0.21 and 4.43 ± 0.38 Gy, respectively) were significantly elevated compared to outer quadrants (1.02 ± 0.17 and 2.10 ± 0.29 Gy, respectively; p < 0.0001). After the adjustment, the doses in PBI patients were significantly reduced in patients with tumors only in outer quadrants (1.12 ± 0.20 and 2.43 ± 0.37 Gy, respectively; p = 0.0001).ConclusionsTumor control and dose to LAD should be considered during treatment since PBI may reduce the risk of coronary artery disease especially in patients with lateral tumors in the left breast.

Cardiac Substructure Segmentation and Dosimetry Using a Novel Hybrid Magnetic Resonance and Computed Tomography Cardiac Atlas

“…The retrospective dosimetric evaluation revealed that for whole breast RT, few cardiac substructures may require assessment. Nevertheless, the maximum dose to the LADA (46.2 ± 6.8 Gy) was substantial, with possible consequences of acute cardiac events [10] and ischemic heart disease [9,34]. Future work may include the evaluation of treatment planning strategies and extend this work to other disease sites that may benefit from cardiac substructure sparing (e.g., esophagus, lung, or lymphoma).…”

“…Dosimetric evaluation of the cardiac substructures included measurements of the minimum, mean, and maximum dose to each substructure. The mean heart dose (MHD), left ventricular volume receiving 5 Gy (LV-V5) and left anterior descending artery mean and maximum doses (LADA mean , LADA max ) are highlighted as they have been shown to be predictive of acute cardiac events [4,10] and are important indicators for ischemic heart disease [9,34].…”

Radiation dose to the left anterior descending coronary artery during interstitial pulsed-dose-rate brachytherapy used as a boost in breast cancer patients undergoing organ-sparing treatment

“…In the literature, there are limited data of LAD doses during breast irradiation, with only two published reports considering multi-catheter high-dose-rate BT (HDR-BT) as a form of APBI [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ] ( Table 5 ). Chan et al .…”

“…In Sato et al . [ 19 ] study, which compared radiation dose to the LAD during HDR-BT APBI and WBRT, LAD was outlined as in our series, but in uncertain BT cases each artery was identified with reference to the preoperative enhanced CT images to determine LAD. In the BT group (100 cases), mean PTV was 35.8 cc (6.8-135.8), mean V 100 29.8 cc (7.0-106.5), and mean DNR was 0.3 (0.2-0.6).…”

Whole breast irradiation vs. APBI using multicatheter brachytherapy in early breast cancer – simulation of treatment costs based on phase 3 trial data

“…However, these possible limitations seem to be overestimated in comparison with the strengths of the present study, which clearly shows a large difference of costs. Moreover, we assumed that an optimal distribution of radiation to critical organs, being characteristic feature of interstitial APBI, is likely reflected by lesser risk of complications and consequently, lower costs of their management [24]. Furthermore, late results of APBI and WBI were previously a subject of a 12-year matched-pair analysis, which demonstrated the two methods, do not differ significantly in terms of overall survival, local and regional control rates [18].…”