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Breast cancer is a highly prevalent disease worldwide, with adjuvant radiation therapy (RT) being considered standard of care after breast-conserving surgery (BCS). Older patient population can present multiple running comorbidities and less aggressive tumor behavior, and the absolute impact of adjuvant RT on local control can be low. This article aims to review the available literature about the impact of adjuvant RT, discussing characteristics to identify lower risk cases, and advantages and disadvantages of the omission of adjuvant radiotherapy in this group.

The Total Skin Electron Beam (TSEB) irradiation is a radiotherapeutic technique that aims to provide the patient's skin surface with a more homogeneous dose, in order to treat cutaneous T-cell lymphomas, both for curative and palliative purposes. Electron irradiation penetrates a few millimeters into the skin, reaching the affected parts completely, without penetrating the internal organs. In vivo dosimetry has become an important role for the treatment of total skin irradiation within a rigorous quality assurance program that should be an integral part of the radiotherapy departments. The use of TLDs in vivo can identify variations in the prescribed dose because its measurement accuracy and great precision. The LiF:Mg,Ti is the most used TL material and widely studied in radiotherapy dosimetry due to near tissue-equivalence of the material, along with its overall reliability. The dosimeters of μLiF:Mg,Ti have been gaining considerable importance in the radiotherapy departments. These detectors allow measurements in vivo with great advantages due to their minimum dimensions of 1 × 1 × 1 mm3. This paper reports a comparative study of the TL responses of both materials to dose evaluation in TSEB treatments. The TL response of both materials in several TSEB parameter tests and in clinical application were evaluated, analyzing the dose distribution in a treatment simulation using AldersonRando anthropomorphic phantom. The results showed that the μLiF:Mg,Ti presented greater variation of the response in relation to LiF dosemeters in some parameters analyzed, due to the small dimensions and to evaluate doses absorbed in the surface over a large area in the treatment plan.

The commissioning and quality assurance The Total Skin Electron Beam (TSEB) irradiation treatment is based on the AAPM's report 23, which describes the six-dual-field (Standford) technique, and the Hospital Israelita Albert Einstein (HIAE) follows this recommended guidance. The Dosimetric Materials Laboratory of the Instituto de Pesquisas Energeticas e Nucleares (IPEN-LMD) has tradition in research related to thermoluminescent materials and its clinical applications. Thus, aiming to apply the LiF:Mg,Ti, the most common TLD material, and CaSO4:Dy + Teflon produced at IPEN as easy-to-use alternatives to electron beams dosimetry and its parameters applied to TSEB, this paper reports a comparative study of the TL responses of both materials to dose evaluation in TSEB treatments. The TL response of both materials was evaluated in several TSEB parameter tests such as clinical field homogeneity, Monitor Units (MU) calculation, absorbed doses over the reference line and throughout the surface of the skin in a treatment simulation using AldersonRando anthropomorphic phantom. Results show that the field homogeneity measurements remained within ± 8% acceptance limit from AAPM Report 23, little to no energy dependency over the range of 4 o 9 MeV electron beams and, for clinical measurements and MU calculations, both TLDs present compatible results and can be used as alternative tools in TSEB dosimetry.

Thermoluminescent dosimeters (TLDs) play an important role in radiotherapy for the dosimetry of ionizing radiation. This type of dosimeter presents advantages that makes them a useful tool for measurements in anthropomorphic phantoms and in vivo dosimetry. Several dosimetric materials have been used in the radiotherapy sectors such as LiF, µLiF, CaSO4:Dy. The OSL dosimetry has also been widely applied using Aluminum Oxide (Al2O3:C). These dosimeters have advantages over TLDs due to their high sensitivity, extensive linearity in response to the dose, faster reading, possibility of multiple readings and the need to perform the heat treatment of the samples. The aim of this work was to compare and characterize, using TL and OSL techniques, different luminescent dosimeters (LiF, µLiF, CaSO4:Dy and Al2O3:C) to be applied in clinical electron beam used to TSEB treatments. Measurements were performed in order to study the applicability of these detectors as easy-to-take alternatives to calibration and measurements of TSEB treatments. Parameters such as dose-response curves; average sensitivity to radiation, intrinsic efficiency and energy and angular dependences were evaluated. The results show good agreement within CaSO4:Dy and TLD-100 measurements and, applying energy and angle dependence factors over the other two materials, all the four detectors can be applied as alternative easy-to-take dosimetric tools for commissioning and quality assurance of 6 MeV clinical electron beams used in TSEB treatments.

Background Obesity is a chronic complex disease with an increasing prevalence around the world. Prospective studies in adult cohorts are needed to provide information about predictors of new-onset overweight/obesity on population-based levels. The aim of this study was to identify factors associated with the risk of an adult individual become overweight/obese after 13 years of follow-up. Methods Second phase of an observational population-based prospective cohort study in a small town in the Midwest region of Brazil. A representative sample of the adult population (≥18 years) was assessed in 2002 (phase 1). Anthropometric, sociodemographic, dietary intake and lifestyle data were collected. After 13 years of follow-up (2015), the same variables were re-evaluated (phase 2). New-onset overweight/obesity was the outcome variable. Results A total of 685 subjects were included with a mean age in phase 1 of 42.7 ± 13.8 years and 56.1 ± 13.8 years in phase 2, the mean follow-up time was 13.2 years and female sex counted for 66.3% of the sample. Total weight gain was 5.9 ± 10.2 Kg, body mass index increased 2.6 ± 3.8 Kg/m2 and waist circumference (WC) values increased 8.0 ± 10.5 cm. The prevalence of overweight/obesity went from 49.1% in phase 1 to 69.8% in phase 2 (p

Background Reduced-intensity conditioning (RIC) regimens provide insufficient disease control in patients with high-risk hematological malignancies who are ineligible for myeloablative hematopoietic cell transplantation (HCT) due to advanced age or comorbidities. RIC fludarabine/busulfan (Flu/Bu) is generally well tolerated, but is associated with high relapse rates. We hypothesized that intensification of RIC Flu/Bu with targeted marrow irradiation (TMI) would be feasible and improve outcomes in such patients. Methods This dose escalation phase I clinical trial incorporated 3+3 design with expansion. The primary endpoint was to estimate safety and feasibility of TMI combined with Flu/Bu. Secondary endpoints included transplant-related mortality (TRM), disease free survival (DFS) and overall survival (OS). Eligible patients were ≥ 18 years diagnosed with high-risk hematological malignancies who were not candidates for myeloablative HCT. The conditioning regimen consisted of TMI (dose levels: 3 Gy, 4.5 Gy and 6 Gy) delivered at 1.5 Gy/fraction in twice daily fractions on days -10 through -7, fludarabine (30 mg/m2) on days -6 through -2 and busulfan (AUC 4800 µM*minute) on days -5 and -4. Radiation was targeted to bone marrow and spleen using intensity modulated radiation therapy (IMRT) technique while minimizing injury to organs at risk. GVHD prophylaxis included tacrolimus and methotrexate for matched sibling and unrelated donors (UD), and tacrolimus, mycophenolate mofetil and post-cyclophosphamide for haploidentical donors. Antithymocyte globulin (ATG) was added for recipients of UD transplants. Dose limiting toxicity (DLT) was defined as engraftment failure, grade ≥ 4 mucositis and grade ≥ 3 other non-hematological adverse events (AEs) from day -10 to day +32. Results A total of 26 patients (median age 64 years [range, 25-76]; 61% females) were enrolled in two transplant centers (Table 1). Diagnoses included AML (n=15), MDS (n=5), T-PLL (n=2), CLL (n=1), DLBCL (n=1), multiple myeloma (n=1) and myeloproliferative disorder (n=1). Sixteen (61%) patients had intermediate/high HCT-comorbidity index and high/very high disease risk index (DRI). At the time of HCT, 19 (73%) patients had active or residual disease. Donors were UD (n=18), matched sibling (n=5) and haploidentical (n=3). All patients engrafted neutrophils (median, 16 days [range, 10-29]). Most frequent AEs were mucositis (65%), gastrointestinal toxicity (62%), hepatotoxicity (hyperbilirubinemia and/or increased transaminase levels) (65%) and fatigue (69%). Twenty-four grade ≥ 3 AEs occurred in 13 patients; 2 patients experienced reversible DLT (mucositis and hepatotoxicity) at 6 Gy TMI dose level. Additional escalation was halted and 6 Gy cohort was expanded. Only 1 patient experienced reversible hepatotoxicity in the expansion cohort. Grade II-IV and III-IV acute GVHD rates at day +100 were 57% (95% CI, 39%-84%) and 22% (95% CI, 9%-53%), respectively. The 1-year cumulative incidence of chronic GVHD was 42% (95% CI, 24%-74%). The 1-year cumulative incidence of TRM and relapse was 8% (95% CI, 2%-32%) and 26% (95% CI, 13%-52%), respectively (Figure 1A). The overall TRM for 3 Gy, 4.5 Gy and 6 Gy cohorts was 25%, 12.5% and 12%, respectively. With a median follow up of 12.7 months (range, 1.1-36.8), 1-year DFS was 55% (95% CI, 34%-76%) and OS was 65% (95% CI, 46%-85%) (Figure 1B). One-year DFS was equivalent for patients transplanted in CR or with active disease (54% [95% CI, 14%-93%] vs 55% [95% CI, 29%-80%]; p=0.83) (Figure 1C). While no difference in DFS was observed between the 4.5 Gy and 6 Gy cohorts, the 3 Gy cohort was associated with inferior DFS (p=0.004) (Figure 1D). One-year DFS and OS for 6 Gy cohort was 58% (95% CI, 30%-87%) and 82% (95% CI, 59%-100%), respectively. Conclusion Intensification of RIC Flu/Bu with TMI is feasible, with low incidence of TRM in medically frail patients. Reversible mucositis and hepatotoxicity prevented dose escalation beyond 6 Gy. DFS and OS at 6 Gy are promising and deserve further investigation. Disclosures Malek: Janssen: Other: Advisory board, Speakers Bureau; Medpacto: Research Funding; Sanofi: Other: Advisory board; Clegene: Other: Advisory board , Speakers Bureau; Amgen: Honoraria; Takeda: Other: Advisory board , Speakers Bureau; Bluespark: Research Funding; Cumberland: Research Funding. de Lima:Pfizer: Other: Personal fees, advisory board, Research Funding; Celgene: Research Funding; Kadmon: Other: Personal Fees, Advisory board; Incyte: Other: Personal Fees, advisory board; BMS: Other: Personal Fees, advisory board. Caimi:Amgen: Other: Advisory Board; Bayer: Other: Advisory Board; Verastem: Other: Advisory Board; Kite pharmaceuticals: Other: Advisory Board; ADC therapeutics: Other: Advisory Board, Research Funding; Celgene: Speakers Bureau.

The Total Skin Electron Beam (TSEB) therapy is a technique that aims to provide skin surface homogeneous absorbed dose in order to treat cutaneous T-cell lymphomas, both for curative and palliative purposes with electron beams penetrating a few millimeters into the skin, reaching the affected parts without affecting internal organs. In vivo dosimetry has become an important role for the treatment of total skin irradiation within a rigorous quality assurance. The luminescent dosimeters, such as TLDs and OSLDs, have proven to be very useful for the verification of the dose distribution and prescribed for the patient as the dose may differ from place to place due to patient body geometry, overlapping of structures and asymmetries of the radiation field. Other routine in vivo dosimetry tool is the DIODEs and they as well help validating radiation therapy dosimetry. Al2O3:C OSL pellets manufactured and marketed by REXON Components and TLD Systems have already been characterized for TSEB applications. The aim of this work is to compare the performance of Al2O3:C OSL pellets from REXON to in vivo TSEB dosimetry with silicon DIODEs QEDTM detectors from Sun Nuclear (EUA) using an anthropometric phantom. Dosimeters and DIODEs were previously characterized for 6 MeV HDTSe- electron beams and then placed over an Anderson Rando® anthropomorphic phantom, evaluating the body dose distribution. The reference point of measurement was the umbiculous as recommended by formalism. The results showed that the Al2O3:C OSL pellets presented acceptable results, but some greater variation of the response in relation to silicon DIODEs were found due to its considerable rotational dependency.

Background Heart-sparing techniques are time and resource intensive, although not all patients require the use of these strategies. This study evaluates the performance of different distance metrics in predicting the need for breath-hold radiotherapy in left-sided breast cancer patients receiving adjuvant radiotherapy. Methods Fifty left-sided breast cancer patients treated with breast conserving surgery and adjuvant radiotherapy to the breast from a single institution were retrospectively studied. The left breast and organs at risk were contoured in accordance to guidelines and a plan with tangents was obtained using the free-breathing CT in supine position. Heart (mean heart dose (MHD), heart V25 Gy) and left anterior descending artery dosimetry were computed and compared against distance metrics under investigation (Contact Heart, 4th Arch and 5th Arch). Recursive partitioning analysis (RPA) was used to determine optimal cut-points for distance metrics for dosimetric end points. Receiver operating characteristic curves and Pearson correlation coefficients were used to evaluate the association between distance metrics and dosimetric endpoints. Univariable and multivariable logistic regression analysis was performed to identify significant predictors of dosimetric end points. Results The mean MHD and heart V25 Gy were 2.3 Gy and 10.4 cm3, respectively. With tangents, constraints for MHD (

Background The best anthropometric indicator to verify the association between obesity and hypertension (HTN) has not been established. We conducted this study to evaluate and compare the discriminatory power of waist-to-height ratio (WHtR) in relation to body mass index (BMI) and waist circumference (WC) in predicting HTN after 13 years of follow-up. Methods This study was an observational prospective cohort study performed in the city of Firminópolis, in Brazilian’s midwest. The cohort baseline (phase 1) was initiated in 2002 with the evaluation of a representative sample of the normotensive population (≥ 18 years of age). The incidence of HTN was evaluated as the outcome (phase 2). Sociodemographic, dietary and lifestyle variables were used to adjust proportional hazards models and evaluate risk of HTN according to anthropometric indices. The areas under the receiver operating characteristic (ROC) curves were used to compare the predictive capacity of these indices. The best HTN predictor cut-offs were obtained based on sensitivity and specificity. Results A total of 471 patients with a mean age of 38.9 ± 12.3 years were included in phase 1. The mean follow-up was 13.2 years, and 207 subjects developed HTN. BMI, WC and WHtR were associated with risk of HTN incidence and had similar power in predicting the disease. However, the associations were only significant for women. The cut-off points with a better HTN predictive capacity were in agreement with current recommendations, except for the WC in men. Conclusions The results suggest that both overall obesity (BMI) and central obesity (WC and WHtR) anthropometric indicators can be used in this population to evaluate the risk of developing hypertension. Electronic supplementary material The online version of this article (10.1186/s12889-018-5177-3) contains supplementary material, which is available to authorized users.

Cohort studies assessing predictive values of self-rated health (SRH) and illiteracy on mortality in low-to-middle income countries are missing in the literature. Aiming to determine if these two variables were death predictors, an observational prospective population-based cohort study was conducted in a Brazilian small city. The cohort was established in 2002 with a representative sample of adults living in the city, and re-assessed in 2015. Sociodemographic (including illiteracy), anthropometric, lifestyle, previous CVD, and SRH data were collected. Cox proportional hazard models were designed to assess SRH and illiteracy in 2002 as death (all causes, CVD and non-CVD) predictors in 2015. From a total of 1066 individuals included in this study, 95(9%) died of non-CVD causes and 53(5%) from CVD causes. Mortality rates were higher among those with worse SRH in comparison to better health status categories for all causes of death, CVD and non-CVD deaths (p

Total-skin electron beam (TSEB) irradiation is used to deliver a homogeneous dose distribution over the entire skin surface of a patient. TSEB dosimetry is quite complex as to the evaluation and measurement of absorbed dosage in the cutaneous region. This paper evaluates the performance of different dosimetric materials, using TL and OSL dosimetry, in the extremity-dose assessment of TSEB treatments using the six-dual-field technique and an anthropomorphic phantom. Dosimeters were selected with repeatability better than [Formula: see text] and calibrated to 6-MeV electron-beam dosimetry. Measurements were conducted in the abdominal region as a reference point and on the extremities. Results show expected deviations ranging up to [Formula: see text] in the dose received in the extremities and good results in dose assessment using all dosimetric materials tested.