Aim
To assess the impact of age, comorbidities and endocrine therapy (ET) in older breast cancer (BC) patients treated with hypofractionated radiotherapy (Hypo-RT).
Methods
From June 2009 to December ...2017, we enrolled in this study 735 ER-positive BC patients (stage pT1–T2, pNx–1, M0 and age ≥ 65 years) receiving hypo-RT and followed them until September 2019. Baseline comorbidities included in the hypertension-augmented Charlson Comorbidity Index were retrospectively retrieved. Logistic regression model estimated adjusted-odds ratios (ORs) of ET prescription in relation to baseline patient and tumor characteristics. Competing risk analysis estimated 5-year cumulative incidence function (CIF) of ET discontinuation due to side effects (with BC progression or death as competing events), and its effect on locoregional recurrence (LRR) and distant metastasis (DM) (with death as competing event).
Results
ET has been prescribed in 89% patients. In multivariable analysis, the odds of ET prescription was significantly reduced in older patients (≥ 80 years, OR 0.08, 95% CI 0.03–0.20) and significantly increased in patients with moderate comorbidity. Patients ≥ 80 years discontinued the prescribed therapy earlier and more frequently than younger (65–69 years) patients (
p
= 0.060). Five-year CIF of LLR, DM and death from causes other that BC were 1.7%, 2.2% and 7.5%, respectively. Patients who discontinued ET had higher chance of LRR (
p
= 0.004). ET use did not impact on OS in any of the analyzed groups.
Conclusions
In older patients, ET did not show a benefit in terms of overall survival. Further studies focusing on tailored treatment approaches are warranted to offer the best care in terms of adjuvant treatment to these patients.
•3 MOSkins were assembled over a common rectal probe to perform in vivo dosimetry.•Mean discrepancy between measured and calculated doses was 2.2±6.9%.•89.2% of the measurements resulted in dose ...discrepancies within ±10%.•Discrepancy between planned and measured doses increases with planning time.
Three MOSkins dosimeters were assembled over a rectal probe and used to perform in vivo dosimetry during HDR brachytherapy treatments of vaginal cancer. The purpose of this study was to verify the applicability of the developed tool to evaluate discrepancies between planned and measured doses to the rectal wall.
MOSkin dosimeters from the Centre for Medical Radiation Physics are particularly suitable for brachytherapy procedures for their ability to be easily incorporated into treatment instrumentation. In this study, 26 treatment sessions of HDR vaginal brachytherapy were monitored using three MOSkin mounted on a rectal probe. A total of 78 measurements were collected and compared to doses determined by the treatment planning system.
Mean dose discrepancy was determined as 2.2±6.9%, with 44.6% of the measurements within ±5%, 89.2% within ±10% and 10.8% higher than ±10%. When dose discrepancies were grouped according to the time elapsed between imaging and treatment (i.e., group 1: ≤90min; group 2: >90min), mean discrepancies resulted in 4.7±3.6% and 7.1±5.0% for groups 1 and 2, respectively. Furthermore, the position of the dosimeter on the rectal catheter was found to affect uncertainty, where highest uncertainties were observed for the dosimeter furthest inside the rectum.
This study has verified MOSkin applicability to in-patient dose monitoring in gynecological brachytherapy procedures, demonstrating the dosimetric rectal probe setup as an accurate and convenient IVD instrument for rectal wall dose verification. Furthermore, the study demonstrates that the delivered dose discrepancy may be affected by the duration of treatment planning.
Abstract Purpose To evaluate toxicity in breast cancer patients treated with anthracycline and taxane based chemotherapy and whole breast hypofractionated radiotherapy, and to identify the risk ...factors for toxicity. Methods and materials 537 early breast cancer patients receiving hypofractionated radiotherapy after conservative surgery were enrolled from April 2009 to December 2014, in an Italian cancer institute. The dose was 42.4 Gy in 16 daily fractions, 2.65 Gy per fraction. The boost to the tumor bed was administered only in grade III breast cancer patients and in patients with close or positive margins. Acute and late toxicity were prospectively assessed during and after radiotherapy according to RTOG scale. The impact of patients clinical characteristics, performed treatments and dose inhomogeneities on the occurrence of an higher level of acute skin toxicity and late fibrosis has been evaluated by univariate and multivariate analysis. Results The mean age was 74 (range 46–91 yrs). 27% of patients received boost. 22% of cases (n = 119) received also chemotherapy. The median follow-up was 32 months. G1 and G2/G3 acute skin toxicity were 61.3% and 20.5% and G1 and G2/G3 late fibrosis 12.6% and 4.3% respectively. Chemotherapy (p = 0.04), diabetes (p = 0.04) and boost administration (p < 0.01) were found to be statistically significant on the occurrence of late fibrosis, but a multivariate analysis did not show any factors connected. The boost administration (p < 0.01), the breast volume (p = 0.05), dose inhomogeneities (p < 0.01) and boost volume (p = 0.04) were found to be statistically significant as concerns the occurrence of acute skin reaction at the univariate analysis, but only the boost administration (p = 0.02), at multivariate analysis. Conclusions The results of our study, according to the large randomized trials, confirmed that hypofractionated whole breast irradiation is safe, and only the boost administration seems to be an important predictor for toxicity. Chemotherapy does not impact on acute and late skin toxicity.
Purpose
To report acute toxicities in breast cancer (BC) patients (pts) recruited in a prospective trial and treated with accelerated partial-breast irradiation (APBI) using Volumetric Modulated Arc ...Therapy (VMAT) delivered with a hypofractionated schedule.
Methods
From March 2014 to June 2019, pts with early-stage BC (Stage I), who underwent breast conservative surgery (BCS), were recruited in a prospective study started at the National Cancer Institute of Milan. Pts received APBI with a hypofractionated schedule of 30 Gy in five daily fractions. Radiotherapy treatment (RT) was delivered using VMAT. Acute toxicity was assessed according to RTOG/EORTC criteria at the end of RT.
Results
Between March 2014 and June 2019, 151 pts were enrolled in this study. 79 Pts had right-side and 72 had left-side breast cancer. Median age was 69 (range 43–92). All pts presented with pathological stage IA BC, molecular classification was Luminal A in 128/151 (85%) and Luminal B in 23/151 (15%) cases. Acute toxicity, assessed at the end of RT, consisted of G1 erythema in 37/151 (24. 5%) pts and skin toxicities higher than G1, did not occur. Fibrosis G1 and G2 were reported in 41/151 (27. 1%) pts and in 2/151 pts (1. 3%), respectively. Edema G1 occurred in 8/151 (5. 3%) pts and asthenia G1 occurred in 1/151 (0. 6%) pts.
Conclusions
APBI with VMAT proved to be feasible and can be a valid alternative treatment option after BCS in selected early breast cancer pts according to ASTRO guidelines. A longer follow-up is needed to assess late toxicity.
Purpose: Computed tomography (CT) represents the standard of treatment planning in radiotherapy. Calculation of dose distribution requires proper energy-dependent curves to convert Hounsfield Units ...into relative to water electron densities (rED). To possibly reduce the patient dose while maintaining optimal image quality, it could be useful to modulate x-ray tube potential (kVp) based on patient size, but this practice requires the use of several conversion curves in the treatment planning system (TPS). The DirectDensityTM (DD) algorithm, recently developed by Siemens Healthcare, uses projection data to reconstruct images directly proportional to rEDs, regardless of the used kVp. The purpose of this study was to evaluate this algorithm for clinical use in radiotherapy. Methods: Image quality was evaluated on Catphan images reconstructed with standard and DD algorithms. The CIRS Electron Density Phantom, with its several tissue-equivalent inserts, was then used to assess the accuracy of reconstructed rEDs against those certified at different tube voltages. Finally, the treatment plans calculated on clinical images reconstructed with standard and DD algorithms were compared. Results: DD showed an image quality comparable to standard algorithms except for the contrast: DD causes a loss in contrast (up to 69%) for materials densities greater than 1.1 g cm−3. CIRS images analysis proved the rEDs reconstruction accuracy except for the metal inserts: titanium rED was underestimated up to 40% when kVp was reduced. Nevertheless, minimal dosimetric differences were found between treatment plans calculated in different body regions. Conclusions: The DD algorithm allows to plan radiotherapy treatments on CT images acquired at tube potentials optimized both for the anatomical region and patient size, without complicating the clinical workflow with tube potential specific calibration procedures. However, the presence of contrast medium and metal implants can limit the applications of this algorithm in clinical practice.
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