Cardiac and lung complication probabilities after breast cancer irradiation.
ABSTRACT To assess for locoregional irradiation of breast cancer patients, the dependence of cardiac (cardiac mortality) and lung (radiation pneumonitis) complications on treatment technique and individual patient anatomy.
Three-dimensional treatment planning was performed for 30 patients with left-sided breast cancer and various breast sizes. Two locoregional techniques (Techniques A and B) and a tangential field technique, including only the breast in the target volume, were planned and evaluated for each patient. In both locoregional techniques tangential photon fields were used to irradiate the breast. The internal mammary (IM)-medial supraclavicular (MS) lymph nodes were treated with an anterior mixed electron/photon field (Technique A) or with an obliquely incident mixed electron/photon IM field and an anterior electron/photon MS field (Technique B). The optimal IM and MS electron field dimensions and energies were chosen on the basis of the IM-MS lymph node target volume as delineated on CT-slices. The position of the tangential fields was adapted to match the IM-MS fields. Dose-volume histograms (DVHs) and normal tissue complication probabilities (NTCPs) for the heart and lung were compared for the three techniques. In the beam's eye view of the medial tangential fields the maximum distance of the heart contour to the posterior field border was measured; this value was scored as the Maximum Heart Distance.
The lymph node target volume receiving more than 85% of the prescribed dose was on average 99% for both locoregional irradiation techniques. The breast PTV receiving more than 95% of the prescribed dose was generally smaller using Technique A (mean: 90%, range: 69-99%) than using Technique B (mean: 98%, range: 82-100%) or for the tangential field technique (mean: 98%, range: 91-100%). NTCP values for excess cardiac mortality due to acute myocardial ischemia varied considerably between patients, with minimum and maximum values of 0.1 and 7.5% (Technique A), 0.1 and 5.8% (Technique B) and 0.0 and 6.1% (tangential tech.). The NTCP values were on average significantly higher (P<0.001) by 1.7% (Technique A) and 1.0% (Technique B) when locoregional breast irradiation was given, compared with irradiation of the left breast only. The NTCP values for the tangential field technique could be estimated using the Maximum Heart Distance. NTCP values for radiation pneumonitis were very low for all techniques; between 0.0 and 1.0%.
Technique B results in a good coverage of the breast and locoregional lymph nodes, while Technique A sometimes results in an underdosage of part of the target volume. Both techniques result in a higher probability of heart complications compared with tangential irradiation of the breast only. Irradiation toxicity for the lung is low in all techniques. The Maximum Heart Distance is a simple and useful parameter to estimate the NTCP values for cardiac mortality for tangential breast irradiation.
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ABSTRACT: Background and purposes: To compare the dosimetry for the left-sided breast cancer treatment using five different radiotherapy techniques.Materials and methods: Twenty patients with left sided breast cancer were treated with conservative surgery followed by radiotherapy. They were planned using five different radiotherapy techniques, including: 1) conventional tangential wedge-based fields (TW); 2) field-in-field (FIF) technique; 3) tangential inverse planning intensity-modulated radiation therapy (T-IMRT); 4) multi-field IMRT (M-IMRT); and 5) volumetric modulated arc therapy (VMAT). The CTV, PTV and OARs including the heart, the regions of coronary artery (CA), the contralateral breast, the left and right lung were delineated. The PTV dose was prescribed 50Gy and V47.5>=95%. Same dose constraint was used for all five plans. The planned volumetric dose of PTV and PRV-OARs were compared and analyzed. RESULTS: Except VMAT (Average V47.5 was 94.72%+/-1.2%), all the other four plans were able to meet the V95% (V47.5) requirement. T-IMRT plan improved the PTV dose homogeneity index (HI) by 0.02 and 0.03 when compared to TW plan and VMAT plan, and decreased the V5, V10 and V20 of all PRV-OARs. However, the high dose volume (>= 30Gy) of the PRV-OARs in T-IMRT plan had no statistically significant difference compared with the other two inverse plans. In all five plans, the dose volume of coronary artery area showed a strong correlation to the dose volume of the heart (the correlation coefficients were 0.993, 0.996, 1.000, 0.995 and 0.986 respectively). CONCLUSION: Compared to other techniques, the T-IMRT technology reduced radiation dose exposure to normal tissues and maintained reasonable target homogeneity, VMAT is not recommended for left-sided breast cancer treatment. In five techniques, the dose-volume histogram (DVH) of the heart can be used to predict the dose-volume histogram (DVH) of the coronary artery.Radiation Oncology 04/2013; 8(1):89. · 2.11 Impact Factor
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ABSTRACT: The goal of this population-based study was to determine the impact of post-mastectomy radiation therapy on long-term overall survival (OS) of male patients with breast cancer. We investigated 20-year OS rates of 664 patients diagnosed with primary stage I-III breast cancer in former East Germany between 1970 and 1989. Patients had a radical mastectomy with axillary lymph node dissection without systemic adjuvant therapy. Median follow-up time was 26.2 years (range 19-38 years). 52.4% of the patients had post-mastectomy radiotherapy. Radiotherapy showed different effects in each stage group after 20 years. Whereas there was an OS trend for radiotherapy to harm patients with stage I disease (hazard ratio (HR) 1.45; 95% confidence interval (CI) 0.98-2.15; p = 0.065), radiotherapy showed no benefit in patients with stage II disease (HR 0.82; 95% CI 0.62-1.1; p = 0.15). There was a significant survival benefit for patients with stage III disease receiving radiotherapy (HR 0.60; 95% CI 0.41-0.88; p = 0.008). Post-mastectomy radiotherapy is associated with longer OS in male patients with stage III breast cancer. Male breast cancer patients at stages I and II do not seem to benefit from radiotherapy, but obsolete irradiation techniques might explain adverse long-term effects in earlier stages.Breast Care 08/2013; 8(4):270-5. · 0.68 Impact Factor
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ABSTRACT: PurposeProspective monocentric study of the toxicities related to concurrent administration of trastuzumab to breast radiotherapy.Patients and methodsOne hundred and seventy-three patients were treated between June 2003 and March 2009 by concurrent trastuzumab with normofractionated radiotherapy. Trastuzumab was delivered every 3 weeks (8 mg/kg in the first infusion then 6 mg/kg) during a median time of 12 months (2–62). Left ventricular ejection fraction was assessed by echocardiography or cardiac scintigraphy at baseline, before and after radiotherapy, every 3 months for 1 year and annually. A left ventricular ejection fraction strictly lower than 55% was considered as altered. All toxicities were evaluated using Common Terminology Criteria for Adverse Effects version 3.0.ResultsMedian follow-up was 52 months (17–88). Median age was 52 years (25–83). One hundred and thirty-four patients (77.5%) received radiotherapy to the internal mammary chain. Acute grade 1, 2 and 3 epithelitis was described in 132 (76.3%), 32 (18.5%) and six patients (3.4%), respectively. At 23 months, grade 1 and 2 fibrosis was observed in 31 and eight patients, respectively (18.8 and 4.6%). Left ventricular ejection fraction remained normal for 159 patients (91.9%) before radiotherapy. Among them, 18 (11.3%) experienced a left ventricular ejection fraction alteration, eight (5.0%) at the completion of radiotherapy. Congestive heart failure occurred in one patient (0.6%).Conclusions Toxicities related to the association of trastuzumab to breast radiotherapy were mild. Further follow-up is warranted.Cancer/Radiothérapie 06/2013; 17(3):183–190. · 1.48 Impact Factor