Comparison of outcome and toxicity of postoperative intensity-modulated radiation therapy with two-dimensional radiotherapy in patients with soft tissue sarcoma of extremities and trunk.

BACKGROUND: To compare the survival outcomes and late toxicities of postoperative intensity-modulated radiation therapy (IMRT) with two-dimensional radiotherapy (2D-RT) for patients with soft tissue sarcoma (STS) of extremities and trunk. METHODS: 274 consecutive patients with nonmetastatic STS of extremities and trunk treated with postoperative IMRT (n = 187) and 2D-RT (n = 87) were analyzed. Survival was calculated by using Kaplan-Meier method. Independent prognostic factors were identified using Cox stepwise regression analysis for variables with a P-value <0.1 in univariate analysis. RESULTS: With a median follow-up time of 58.1 months, 30 local recurrences, 66 distant metastases, and 40 deaths occurred. Compared to 2D-RT group, the IMRT group had higher 5-year local recurrence-free survival (LRFS) (91.1% vs 80.8%; P = 0.029), distant metastasis-free survival (DMFS) (80.0% vs 69.7%; P = 0.048), disease-free survival (DFS) (75.2% vs 59.2%; P = 0.021), and overall survival (OS) (90.2% vs 81.0%; P = 0.029). Multivariate analysis showed IMRT was an independent favorable factor for LRFS, DMFS, DFS, and OS. For late toxicities, the patients in IMRT group enjoyed lower incidences of ≥Grade 2 joint stiffness (3.9% vs 12.3%; P = 0.041) and ≥Grade 3 fractures (0.0% vs 3.4%; P = 0.25) than those in 2D-RT group. ≥Grade 2 Edema was similar between these two groups (4.8% vs 9.2%; P = 0.183). CONCLUSIONS: When compared with conventional techniques, postoperative IMRT seems to provide better LRFS, DMFS, DFS, and OS and less late toxicities in patients with STS of extremities and trunk, which should be offered as a preferred treatment.

The effective and collective dose to patients undergoing abdominopelvic and trunk computed tomography examinations: A Belgian multicentre study.

OBJECTIVES: This study aims to evaluate the radiation exposure to patients undergoing an abdominopelvic or a chest and abdominopelvic (trunk) CT examination and to assess compliance to imaging referral guidelines. METHODS: To this end, 357 standard abdominopelvic and trunk CT scans were collected from 8 Belgian institutions in 2011 and 2015. Effective dose (E) and collective dose were calculated using CT dose descriptors (CTDIvol and DLP), which were obtained from dose reports generated by the CT scanner. Subsequently, these CT requests were compared against the national referral guidelines to assess compliance. Population estimates for dose and compliance were obtained using multilevel linear regression and generalized estimating equation models. RESULTS: Between 2011 and 2015, a significant decrease of 28% in CTDIvol and DLP was found for abdominopelvic CT. The corresponding E decreased by 27%, and the collective dose by 23%. For trunk CT, a non-significant decrease of 6% was found in CTDIvol and a significant decrease of 14% in both DLP and E. However, the collective dose of trunk examinations increased by 39%. In 2011, 24% of the abdominopelvic examinations were not compliant with the guidelines, whereas this percentage dropped to 17% in 2015. Non-justified examinations accounted for 8% and 12% of all trunk CT scans in 2011 and 2015, respectively. CONCLUSION: Between 2011 and 2015, there was a decrease in dose for patients undergoing abdominopelvic or trunk CT in Belgium. However, a fraction of the estimated doses are linked to unnecessary CT examinations, which should be avoided.

Low-level laser therapy versus trunk stabilization exercises on sternotomy healing after coronary artery bypass grafting: a randomized clinical trial.

The aim of this study was to investigate the effects of low-level laser therapy (LLLT) versus trunk stabilization exercises on sternotomy healing following coronary artery bypass grafting (CABG) surgery. Forty-five male patients who had acute sternal instability post-CABG surgery in the age range of 45-65 years were divided randomly into three equal groups (n = 15). The laser group received LLLT, while the exercise group received trunk stabilization exercises. The control group only received a routine cardiac rehabilitation programme, which was also provided to both the laser and the exercise groups. All groups were offered 12 sessions over 4 weeks. Sternal separation, median sternotomy photographic analysis, pain and activities of daily living (ADL) performance were evaluated pre- and post-treatment. Statistical significance was set at P < 0.05. There was a significant decrease among the laser group in upper-sternal separation, while the exercise and control groups showed a non-significant decrease. In terms of mid-sternal separation, laser and exercise groups showed a significant decrease while the control group showed a non-significant decrease. In terms of lower-sternal separation, the exercise group showed a significant decrease, while the laser and control groups showed a non-significant decrease. Post-treatment between-groups analysis showed a significant difference only among the laser and control groups with regard to upper-sternal separation, while analysis of the laser, exercise and control groups in the case of upper-sternal separation and the between-groups comparison in terms of mid- and lower-sternal separation revealed no significant differences. LLLT and trunk stabilization exercises were found to be the most effective methods for sternotomy healing post-CABG surgery, with LLLT offering superior performance in the case of the upper sternum while trunk stabilization exercises were more effective for the lower sternum.

Body Anatomical UV Protection Predicted by Shade Structures: A Modeling Study.

Shade is an important means of protection against harmful effects of sun ultraviolet (UV) exposure, but not all shades are identically protective. UV rays scattered by the atmosphere and surroundings can reach the skin indirectly. To evaluate the relative contribution of the direct, diffuse, and reflected radiation in UV protection provided by different sizes of shade structure, we used SimUVEx v2, a numeric tool based on 3D graphic techniques and ambient ground UV irradiance. The relative UV exposure reduction was expressed by the predictive protection factor (PPF). Shade structures were found to predominantly reduce exposure from direct radiation (from 97.1% to 99.9% for the upper body areas such as the head and the neck), with greater protection from larger shade structures and structures closer above the subject. Legs were the least protected anatomical zone from any shade structure above the subject with PPF ranging from 18.5% to 68.1%. Throughout the day, except for lower solar zenith angles (SZA), small and high shade structures provide the lowest protection (between 20% and 50%), while small and low shade structure show PPF between 35% and 65% and large and high shade structures reach PPF higher than 60%.

Mitigation measures of electromagnetic field exposure in the vicinity of high frequency welders.

BACKGROUND: Presented information about the welding process and equipment, focusing on the emission of electromagnetic field (EMF) with levels significant in terms of the labor safety regulations in force in Poland - the ordinances of the Minister of Family, Labour and Social Policy that came into force on June 27, 2016 and June 29, 2016 - emerged due to harmonization with European Union directive 2013/35/EU of 26 June 2013 of the European Parliament and the Council. They presented methods of determination of the EMF distribution in the welding machine surroundings and analyzed the background knowledge from the available literature. MATERIAL AND METHODS: The subject of the analysis included popular high frequency welders widely used in the industry. Electromagnetic field measurements were performed in the welder operating place (in situ) during machine normal operations, using measurement methods accordant with labor safety regulations in force in Poland and according to the same guidelines, the EMF distributions and parameters having been described. RESULTS: They presented various scenarios of particular, real examples of excessive exposure to EMF in the dielectric welder surroundings and showed solutions, ranging from simple and costless and ending on dedicated electromagnetic shielding systems, which allowed to reduce EMF exposure in some cases of more than 80% (protection zone ranges) or eliminate dangerous zone presence. CONCLUSIONS: It has shown that in the dielectric welders surrounding, significant EMF strength levels may be the result of errors or omissions which often occur during development, installation, operation or modification of welding machines. It has allowed to present the measures that may significantly reduce the exposure to EMF of workers in the welder surroundings. The role of accredited laboratories in helping in such cases was underlined. Med Pr 2017;68(6):693-703.

Primary tumor sites in relation to ultraviolet radiation exposure and skin visibility correlate with survival in cutaneous melanoma.

The prognostic value of detailed anatomic site and ultraviolet radiation (UVR) exposure patterns has not been fully determined in cutaneous melanoma. Thus, we reviewed medical records for detailed site in a population-based retrospective Swedish patient cohort diagnosed with primary invasive melanoma 1976-2003 (n = 5,973). We followed the patients from date of diagnosis until death, emigration or December 31st 2013, and evaluated melanoma-specific survival by subsite in a multivariable regression model adjusting for established prognostic factors. We found that melanoma on chronic UVR exposure sites (face, dorsum of hands; adjusted HR 0.6; CI 0.4-0.7) and moderately intermittent UVR sites (lateral arms, lower legs, dorsum of feet; HR 0.7; CI 0.6-0.8) were associated with a favorable prognosis compared with highly intermittent sites (chest, back, neck, shoulders and thighs). Further, melanoma on poorly visible skin sites upon self-examination (scalp, retroauricular area, back, posterior upper arms and thighs, buttocks, pubic area; HR 1.3; CI 1.1-1.5) had a worse prognosis than those on easily visible sites (face, chest, abdomen, anterior upper arms and thighs, lower arms and legs, dorsum of hands and feet, palms). In conclusion, highly intermittent UVR exposure sites and poor skin visibility presumably correlate with reduced melanoma survival, independent of established tumor characteristics. A limitation of the study was the lack of information on actual individual UVR exposure.

Surveillance Imaging Patterns and Outcomes Following Radiation Therapy and Radical Resection for Localized Extremity and Trunk Soft Tissue Sarcoma.

BACKGROUND: Optimal surveillance imaging (SI) regimens following radiation therapy (RT) and radical resection for localized soft tissue sarcoma (STS) are unknown and practice patterns vary. METHODS: Between 2006 and 2014, 94 patients with localized STS of the extremity/trunk treated with preoperative RT and radical resection were identified. Timing of local recurrence (LR), distant recurrence (DR), and SI were evaluated. The Kaplan-Meier method was used to determine recurrence-free and overall survival (OS), and the method of recurrence detection (SI or due to signs/symptoms) was determined. RESULTS: Median tumor size was 7.5 cm, and 92% were intermediate/high grade. After a median follow-up of 60 months for surviving patients, 30 patients (32%) recurred, including 5 LRs and 26 DRs. The median time to LR and DR was 36.2 months (range 14.4-65.7) and 10.4 months (range 5.2-76.9), respectively, and the 5-year local recurrence-free survival (RFS), distant RFS, and OS was 95, 71, and 76%, respectively. Local SI was performed for 90% of patients, mostly by magnetic resonance imaging (MRI; 91%). Of the five LRs, two were detected by SI and three had signs/symptoms preceding imaging. All patients underwent distant SI. Of the 26 DRs, 23 (88%) were in the lung. SI detected 22 (85%) DRs, and only 4 of 26 had signs/symptoms prompting imaging. CONCLUSION: Given excellent local control with RT and radical resection for intermediate/high-grade STS of the extremity/trunk, SI of the primary site should be reserved for select patients at high risk of LR. Conversely, due to frequent occurrence of asymptomatic DR in the lungs, periodic lung SI is appropriate. Routine abdominopelvic SI may not be indicated for most histologies.

[Not Available].

OBJECTIVE: To evaluate the efficacy and influential factors for 308 nm excimer laser in the treatment of stable vitiligo patients.
 METHODS: A total of 207 stable vitiligo patients with 1 763 patches were treated with 308 nm excimer laser. Open-label study was carried out to investigate the efficacy and safety regarding the treatment with 308 nm excimer laser, and to compare the response under different conditions including gender, age, duration, lesion location, and hair color.
 RESULTS: After treatment, 560 (31.8%) patches achieved 100% repigmentation, 650 (36.9%) lesions showed 75%-99% repigmentation, 189(10.7%) showed 50%-75% repigmentation, 231(13.1%) showed 25%-49% repigmentation, 108(6.1%) showed 1%-24% repigmentation, 25(1.4%) displayed no response. The rates of total excellent response (50%-100% repigmentation) in underage patients was 86.9%, much higher than that in adult patients (P<0.001). Total excellent response rates was 90.6% in disease duration <2 years, and 40.7% in disease duration ≥2 years. Lesions on the faciocervical region responded better than trunk and limbs, showing 95.4%, 70.3%, and 41.7% total excellent response, respectively. Patients with poliosis showed 54.9% in total excellent response rate, much lower than 84.5% in patients without poliosis(P<0.001). No significant response differences in gender were found.
 CONCLUSION: 308 nm excimer laser is effective and safe in treatment of vitiligo. Aging, disease duration, lesion location, and hair color in lesion may be the influential factors for 308 nm excimer laser in treatment of vitiligo patients.

Reduction in radiation doses from paediatric CT scans in Great Britain.

OBJECTIVE: Although CT scans provide great medical benefits, concerns have been raised about the magnitude of possible associated cancer risk, particularly in children who are more sensitive to radiation than adults. Unnecessary high doses during CT examinations can also be delivered to children, if the scan parameters are not adjusted for patient age and size. We conducted the first survey to directly assess the trends in CT scan parameters and doses for paediatric CT scans performed in Great Britain between 1978 and 2008. METHODS: We retrieved 1073 CT film sets from 36 hospitals. The patients were 0-19 years old, and CT scans were conducted between 1978 and 2008. We extracted scan parameters from each film including tube current-time product [milliampere seconds (mAs)], tube potential [peak kilovoltage (kVp)] and manufacturer and model of the CT scanner. We estimated the mean mAs for head and trunk (chest and abdomen/pelvis) scans, according to patient age (0-4, 5-9, 10-14 and 15-19 years) and scan year (<1990, 1990-1994, 1995-1999 and ≥2000), and then derived the volumetric CT dose index and estimated organ doses. RESULTS: For head CT scans, mean mAs decreased by about 47% on average from before 1990 to after 2000, with the decrease starting around 1990. The mean mAs for head CTs did not vary with age before 1990, whereas slightly lower mAs values were used for younger patients after 1990. Similar declines in mAs were observed for trunk CTs: a 46% decline on an average from before 1990 to after 2000. Although mean mAs for trunk CTs did not vary with age before 1990, the value varied markedly by age, from 63 mAs for age 0-4 years compared with 315 mAs for those aged >15 years after 2000. No material changes in kVp were found. Estimated brain-absorbed dose from head CT scans decreased from 62 mGy before 1990 to approximately 30 mGy after 2000. For chest CT scans, the lung dose to children aged 0-4 years decreased from 28 mGy before 1990 to 4 mGy after 2000. CONCLUSION: We found that mAs for head and trunk CTs was approximately halved starting around 1990, and age-specific mAs was generally used for paediatric scans after this date. These changes will have substantially reduced the radiation exposure to children from CT scans in Great Britain. ADVANCES IN KNOWLEDGE: The study shows that mAs and major organ doses for paediatric CT scans in Great Britain began to decrease around 1990.

The effects of device position on the operator's radiation dose when using a handheld portable X-ray device.

INTRODUCTION: Handheld X-ray devices are now offered in dental practice. Handheld X-ray units challenge the concept of a restricted access to the "controlled area" as they are held by the operator. Although an integral lead shield is provided, the distance from the body is variable, dependent on how the device is held. The aim of this article was to investigate the level of operator dose when using a handheld X-ray device in various positions. MATERIAL AND METHODS: A NOMAD Pro™ Handheld X-ray system (Aribex Inc., Charlotte, NC) fitted with a remote control and mounted on a tripod was used in this study. A maxillofacial phantom ATOM(®) Max Dental and Diagnostic Phantom, model 711 HN (CIRS Inc., Norfolk, VA) was used to simulate the patient's head position. A mannequin was used to represent the operator. Pre-calibrated thermoluminescent dosemeters (TLDs) (Qados, Agar Scientific, Stansted, UK) were placed on the mannequin close to the eyes and at the level of thyroid, trunk, waist, hand (right finger + left palm) and feet, and three TLDs were used for background radiation. Three test scenarios were investigated; Position 1, close to operators' body and parallel to the ground; Position 2, away from the body with the arms fully extended (approximately 40 cm distance) and parallel to the ground; Position 3, perpendicular to the ground while the arms are partially extended. 30 exposures each of 1 s were performed in each test. RESULTS: Background radiation was measured at 0.0110 mGy. The highest exposure after subtracting background radiation was recorded on the palm of the left hand (0.0310 mGy) at Position 3. The estimated dose to the operator was calculated based on an average workload of 100 intraoral radiographs weekly for a dental practitioner working 46 weeks a year. CONCLUSIONS: There is a negligible increase in operator exposure levels using handheld X-ray devices which remain well below the recommended levels of the Ionizing Radiation Regulations 1999. They could however represent an increase from what should be a nil exposure when using a wall-mounted machine. The position of the device relative to the operator has a significant effect on the overall operator's radiation exposure. The use of personal dosemeters is highly recommended to ensure a continuity of low radiation dose exposure. Furthermore, guidance, training and protocols on usage must be in place, strictly adhered to and regular audits are necessary to ensure compliance.

Occupational radiation exposure of medical staff performing 9°Y-loaded microsphere radioembolization.

PURPOSE: Radioembolization of liver cancer with (90)Y-loaded microspheres is increasingly used but data regarding hospital staff exposure are scarce. We evaluated the radiation exposure of medical staff while preparing and injecting (90)Y-loaded glass and resin microspheres especially in view of the increasing use of these products. METHODS: Exposure of the chest and finger of the radiopharmacist, nuclear medicine physician and interventional radiologist during preparation and injection of 78 glass microsphere preparations and 16 resin microsphere preparations was monitored. Electronic dosimeters were used to measure chest exposure and ring dosimeters were used to measure finger exposure. RESULTS: Chest exposure was very low for both products used (<10 µSv from preparation and injection). In our experience, finger exposure was significantly lower than the annual limit of 500 mSv for both products. With glass microspheres, the mean finger exposure was 13.7 ± 5.2 µSv/GBq for the radiopharmacist, and initially 17.9 ± 5.4 µSv/GBq for the nuclear medicine physician reducing to 13.97 ± 7.9 µSv/GBq with increasing experience. With resin microspheres, finger exposure was more significant: mean finger exposure for the radiopharmacist was 295.1 ± 271.9 µSv/GBq but with a reduction with increasing experience to 97.5 ± 35.2 µSv/GBq for the six most recent dose preparations. For administration of resin microspheres, the greatest mean finger exposure for the nuclear medicine physician (the most exposed operator) was 235.5 ± 156 µSv/GBq. CONCLUSION: Medical staff performing (90)Y-loaded microsphere radioembolization procedures are exposed to safe levels of radiation. Exposure is lower than that from treatments using (131)I-lipiodol. The lowest finger exposure is from glass microspheres. With resin microspheres finger exposure is acceptable but could be optimized in accordance with the ALARA principle, and especially in view of the increasing use of radioembolization.

Possible risks due to exposure of workers and patients with implants by TETRA transmitters.

Several studies have demonstrated that mobile telephones that use different technologies, such as Global System for Mobile Communication (GSM) or Universal Mobile Telecommunication System (UMTS), have the potential to influence the functionality of active electronic implants, including cardiac pacemakers. According to these studies, a few safety measures, such as maintaining minimum distances of 25 cm between implants and transmitters, are sufficient to avoid such effects. Terrestrial Trunked Radio (TETRA) has become a well-established communication standard in many countries, including Germany and Austria. TETRA transmitters are typically used by police forces and emergency services. Employees and volunteers working for such institutions are often in close contact with patients, causing TETRA transmitters to potentially have an impact on the functionality of the implants of patients. Therefore, the main focus of our study was to investigate the functionality of several types of implants when exposed to TETRA transmitters. Moreover, we investigated the difference in the degree of exposure of users of TETRA transmitters when they carry the devices in different locations near the body, and when they use them in different positions near the head. Our results show that a compliance distance of 30 cm between implant and transmitter is sufficient to exclude any influence on the examined implants. All examined exposure conditions demonstrated that the levels were well below recommended limits. If a user wants to minimize their exposure, use of transmitters in front of the mouth leads to somewhat lower exposure when compared to typical mobile phone like use.

The feasibility of using a conventional flexible RF coil for an online MR-guided radiotherapy treatment.

The purpose of this paper is to evaluate the impact of a flexible radiofrequency coil on the treatment delivery of an online MR-guided radiotherapy treatment. For this study, we used a Synergy MR body coil (Philips, Best) in combination with the current MRL prototype of the UMC Utrecht. The compatibility of the coil is evaluated in two steps. First, we evaluated the dosimetric impact of the MR coil on both a simple and a complex irradiation strategy for treating spinal bone metastases. This tumor site will likely be chosen for the first in-man treatments with the UMC Utrecht MRL system. Second, we investigated the impact of the treatment beam on the MRI performance of the body coil. In case a single posterior-anterior rectangular field was applied, dose to the target volume was underestimated up to 2.2% as a result of beam attenuation in the MR coil. This underestimation however, decreased to 1% when a stereotactic treatment strategy was employed. The presence of the MR coil in or near the distal site of the treatment beam decreased the exit dose when a magnetic field was present. The MRI performance of the coil was unaffected as the result of the radiation. It is feasible to use the Synergy MR body coil for an online MR-guided radiotherapy treatment without any modification to the coil or attenuation correction methods in the planning stage. The effect of the MRI coil on the dose delivery is minimal and there is no effect of the treatment beam on the SNR of the acquired MRI data.

[Analysis of methods for measurement and assessment of occupational exposure to electromagnetic fields in dielectric heating]. / Analiza metod pomiarowych i oceniajacych ekspozycje zawodowa na pola elektromagnetyczne stosowane w nagrzewnictwie pojemnosciowym.

BACKGROUND: High-frequency (HF) welders are the most common devices that make use of dielectric heating. They are a source of high-intensity electromagnetic fields (EMFs). Manual operation of those welders makes that the limbs are exposed to EMFs of extremely high intensity, far in excess of the currently admissible values. The aim of this study was to update knowledge of actual exposure of HF welder operators to EMF and to optimize the procedure of exposure assessment. MATERIAL AND METHODS: Measurements of the EMF intensity in the vicinity of 10 dielectric welders at work posts of 12 operators were performed. EMF measurements were made using the reference method, extended by auxiliary measurement points to measure induced currents I(L) in the limbs. Induced current measurements were performed in 20 operators tending the same HF welder. RESULTS: the highest values of the electric (E) and magnetic (H) fields measured at work posts were for whole body: E, up to 350 V/m, and H, up to 1.00 A/m; and for limbs: E, up to 600 V/m and H, up to 3.30 A/m. The W exposure indicator in the primary vertical measurement points was almost as high as 60. I(L) values measured at the wrist exceeded 64 mA and were individual-operator-dependent. CONCLUSIONS: EMF exposure of 25% of HF welder operators exceeded the national admissible values and after taking into account the operators' hands, this figure rose to 50%. The measured value of I(L), representing a measure of internal exposure to EMF, should serve as the main criterion in deciding whether working conditions are admissible.