PURPOSE: Craniospinal irradiation (CSI) has greatly increased survival rates for patients with a diagnosis of medulloblastoma and other primitive neuroectodermal tumors. However, as it includes exposure of a large volume of healthy tissue to unwanted doses, there is a strong concern about the complications of the treatment, especially for the children. To estimate the risk of second cancers and other unwanted effects, out-of-field dose assessment is necessary. The purpose of this study is to evaluate and compare out-of-field doses in pediatric CSI treatment using conventional and advanced photon radiotherapy (RT) and advanced proton therapy. To our knowledge, it is the first such comparison based on in-phantom measurements. Additionally, for out-of-field doses during photon RT in this and other studies, comparisons were made using analytical modeling. METHODS: In order to describe the out-of-field doses absorbed in a pediatric patient during actual clinical treatment, an anthropomorphic phantom, which mimics the 10-year-old child, was used. Photon 3D-conformal RT (3D-CRT) and two advanced, highly conformal techniques: photon volumetric-modulated arc therapy (VMAT) and active pencil beam scanning (PBS) proton RT were used for CSI treatment. Radiophotoluminescent and poly-allyl-diglycol-carbonate nuclear track detectors were used for photon and neutron dosimetry in the phantom, respectively. Out-of-field doses from neutrons were expressed in terms of dose equivalent. A two-Gaussian model was implemented for out-of-field doses during photon RT. RESULTS: The mean VMAT photon doses per target dose to all organs in this study were under 50% of the target dose (i.e., <500 mGy/Gy), while the mean 3D-CRT photon dose to oesophagus, gall bladder, and thyroid, exceeded that value. However, for 3D-CRT, better sparing was achieved for eyes and lungs. The mean PBS photon doses for all organs were up to three orders of magnitude lower compared to VMAT and 3D-CRT and exceeded 10 mGy/Gy only for the oesophagus, intestine, and lungs. The mean neutron dose equivalent during PBS for eight organs of interest (thyroid, breasts, lungs, liver, stomach, gall bladder, bladder, prostate) ranged from 1.2 mSv/Gy for bladder to 23.1 mSv/Gy for breasts. Comparison of out-of-field doses in this and other phantom studies found in the literature showed that a simple and fast two-Gaussian model for out-of-field doses as a function of distance from the field edge can be applied in a CSI using photon RT techniques. CONCLUSIONS: PBS is the most promising technique for out-of-field dose reduction in comparison to photon techniques. Among photon techniques, VMAT is a preferred choice for most of out-of-field organs and especially for the thyroid, while doses for eyes, breasts, and lungs are lower for 3D-CRT. For organs outside the field edge, a simple analytical model can be helpful for clinicians involved in treatment planning using photon RT but also for retrospective data analysis for cancer risk estimates and epidemiology in general.
- MeSH
- celková dávka radioterapie MeSH
- dítě MeSH
- konformní radioterapie * metody MeSH
- kraniospinální iradiace * škodlivé účinky metody MeSH
- kritické orgány účinky záření MeSH
- lidé MeSH
- nádory mozečku * radioterapie MeSH
- plánování radioterapie pomocí počítače metody MeSH
- protony MeSH
- radioterapie s modulovanou intenzitou * škodlivé účinky metody MeSH
- retrospektivní studie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND AND PURPOSE: To update the digital online atlas for organs at risk (OARs) delineation in neuro-oncology based on high-quality computed tomography (CT) and magnetic resonance (MR) imaging with new OARs. MATERIALS AND METHODS: In this planned update of the neurological contouring atlas published in 2018, ten new clinically relevant OARs were included, after thorough discussion between experienced neuro-radiation oncologists (RTOs) representing 30 European radiotherapy-oncology institutes. Inclusion was based on daily practice and research requirements. Consensus was reached for the delineation after critical review. Contouring was performed on registered CT with intravenous (IV) contrast (soft tissue & bone window setting) and 3 Tesla (T) MRI (T1 with gadolinium & T2 FLAIR) images of one patient (1 mm slices). For illustration purposes, delineation on a 7 T MRI without IV contrast from a healthy volunteer was added. OARs were delineated by three experienced RTOs and a neuroradiologist based on the relevant literature. RESULTS: The presented update of the neurological contouring atlas was reviewed and approved by 28 experts in the field. The atlas is available online and includes in total 25 OARs relevant to neuro-oncology, contoured on CT and MRI T1 and FLAIR (3 T & 7 T). Three-dimensional (3D) rendered films are also available online. CONCLUSION: In order to further decrease inter- and intra-observer OAR delineation variability in the field of neuro-oncology, we propose the use of this contouring atlas in photon and particle therapy, in clinical practice and in the research setting. The updated atlas is freely available on www.cancerdata.org.
- MeSH
- antitumorózní látky toxicita MeSH
- časná detekce nádoru MeSH
- karcinogeny toxicita MeSH
- kardiotoxicita * diagnóza etiologie MeSH
- kardiotoxiny toxicita MeSH
- kritické orgány MeSH
- lidé MeSH
- nádorové biomarkery MeSH
- rizikové faktory kardiovaskulárních chorob MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- kongresy MeSH
- zprávy MeSH
BACKGROUND: The purpose of this study was to estimate the additional risk of side effects attributed to internal mammary node irradiation (IMNI) as part of regional lymph node irradiation (RNI) in breast cancer patients and to compare it with estimated overall survival (OS) benefit from IMNI. MATERIAL AND METHODS: Treatment plans (n = 80) with volumetric modulated arc therapy (VMAT) were calculated for 20 patients (4 plans per patient) with left-sided breast cancer from the prospective GATTUM trial in free breathing (FB) and in deep inspiration breath hold (DIBH). We assessed doses to organs at risk ((OARs) lung, contralateral breast and heart) during RNI with and without additional IMNI. Based on the OAR doses, the additional absolute risks of 10-year cardiac mortality, pneumonitis, and secondary lung and breast cancer were estimated using normal tissue complication probability (NTCP) and risk models assuming different age and risk levels. RESULTS: IMNI notably increased the mean OAR doses. The mean heart dose increased upon IMNI by 0.2-3.4 Gy (median: 1.9 Gy) in FB and 0.0-1.5 Gy (median 0.4 Gy) in DIBH. However, the estimated absolute additional 10-year cardiac mortality caused by IMNI was <0.5% for all patients studied except 70-year-old high risk patients (0.2-2.4% in FB and 0.0-1.1% in DIBH). In comparison to this, the published oncological benefit of IMNI ranges between 3.3% and 4.7%. The estimated additional 10-year risk of secondary cancer of the lung or contralateral breast ranged from 0-1.5% and 0-2.8%, respectively, depending on age and risk levels. IMNI increased the pneumonitis risk in all groups (0-2.2%). CONCLUSION: According to our analyses, the published oncological benefit of IMNI outweighs the estimated risk of cardiac mortality even in case of (e.g., cardiac) risk factors during VMAT. The estimated risk of secondary cancer or pneumonitis attributed to IMNI is low. DIBH reduces the estimated additional risk of IMNI even further and should be strongly considered especially in patients with a high baseline risk.
- MeSH
- celková dávka radioterapie * MeSH
- kritické orgány MeSH
- lidé MeSH
- nádory prsu radioterapie MeSH
- nemoci srdce mortalita MeSH
- plánování radioterapie pomocí počítače MeSH
- prospektivní studie MeSH
- radiační poranění mortalita MeSH
- radioterapie škodlivé účinky mortalita MeSH
- senioři MeSH
- srdce účinky záření MeSH
- zadržování dechu MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
It is well known that radiation damage of the pharyngeal constrictor muscles, the glottic larynx, and the supraglottic larynx may lead to dysphagia, an unwanted effect of head and neck radiotherapy. The reduction of radiotherapy-induced dysphagia might be achieved by adaptive radiotherapy. Although the number of studies concerning adaptive radiotherapy of head and neck cancer is continuously increasing, there are only a few studies concerning changes in dysphagia-related structures during radiotherapy.The goal of this review is to summarize the current knowledge about volumetric, dosimetric, and other changes of the pharyngeal constrictor muscles associated with head and neck radiotherapy. A literature search was performed in the MEDLINE database according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The conclusions of 8 studies that passed the criteria indicate a significant increase in the volume and the thickness of the pharyngeal constrictor muscles during radiotherapy. Moreover, the changes in magnetic resonance imaging signal intensity of the pharyngeal constrictor muscles correlate with the absorbed dose (typically higher than 50 Gy) and also with the grade of dysphagia. This systematic review presents 2 variables, which are suitable for estimation of radiotherapy-related pharyngeal constrictor muscles changes-magnetic resonance imaging signal intensity and the thickness. In the case of the thickness, there is no consensus in the level of the measurement-C2 vertebra, C3 vertebra, and the middle of the craniocaudal axis are used. It seems that reference to a position associated with a vertebral body could be more reproducible and beneficial for future research. Although late pharyngeal toxicity remains a challenge in head and neck cancer treatment, better knowledge of radiotherapy-related changes in the pharyngeal constrictor muscles contributes to adaptive radiotherapy development and thus improves the treatment results.
- MeSH
- celková dávka radioterapie MeSH
- faryngální svaly diagnostické zobrazování patologie účinky záření MeSH
- kritické orgány * MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- nádory hlavy a krku komplikace diagnostické zobrazování radioterapie MeSH
- počítačová rentgenová tomografie MeSH
- poruchy polykání etiologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- metaanalýza MeSH
- práce podpořená grantem MeSH
About 26 000 patients are treated per year with radiotherapy for non-malignant diseases in the Czech Republic. Approximately 75% of them are treated on X-ray therapy units and most of these patients undergo radiotherapy of heel spurs. The evaluation of radiation exposure of these patients was based on measured organ doses and on data from clinical practice. Collective effective doses for particular diagnoses were calculated in order to compare doses resulting from different diagnoses treated on X-ray therapy units. The collective effective dose from radiotherapy of heel spurs in the Czech Republic in 2013 was evaluated to 77 manSv. It represents 25.6% of the total collective effective dose for all diagnoses of radiotherapy for non-malignant diseases treated on X-ray therapy units.
- MeSH
- celková dávka radioterapie MeSH
- fantomy radiodiagnostické * MeSH
- kritické orgány účinky záření MeSH
- lidé MeSH
- monitorování radiace metody MeSH
- ostruha kosti patní radioterapie MeSH
- plánování radioterapie pomocí počítače metody MeSH
- radiační expozice analýza MeSH
- rentgenová terapie metody MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
The pilot dose survey on paediatric general radiography, fluoroscopy and CT procedures was performed in four university hospitals. The analysis of data was focused on the radiography and CT imaging of head, chest, abdomen, pelvis and spine and fluoroscopic procedures of gastrointestinal and urinary tracts. The survey was conducted by the National Radiation Protection Institute. Two hospitals exported data from the patient dose management system, while the others collected the data manually. The methodology of diagnostic reference levels assessment was proposed and tested. Local diagnostic reference levels were calculated in terms of air kerma-area product $P_{KA}$, CT air kerma-length product $P_{KL,CT}$ and volumetric CT air kerma index $C_{VOL}$. The lack of procedure standardisation, e.g. in tube voltage setting irrespective of patient's weight, was revealed at one hospital. Dose and exposure parameters distributions with respect to patient's anatomical constitution are presented in this article. In future, this pilot study will be a base for national survey of paediatric diagnostic reference levels.
- MeSH
- dávka záření MeSH
- dítě MeSH
- fluoroskopie metody MeSH
- gastrointestinální nemoci diagnostické zobrazování MeSH
- intervenční radiografie metody MeSH
- kritické orgány účinky záření MeSH
- lidé MeSH
- pilotní projekty MeSH
- počítačová rentgenová tomografie metody MeSH
- počítačové zpracování obrazu metody MeSH
- radiační expozice analýza MeSH
- radiační ochrana MeSH
- urologické nemoci diagnostické zobrazování MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Breast cancer radiotherapy may in the long term lead to radiation-induced secondary cancer or heart disease. These health risks hugely vary among patients, partially due to anatomy-driven differences in doses deposited to the heart, ipsilateral lung and contralateral breast. We identify four anatomic features that largely cover these dosimetric variations to enable personalized risk estimates. For three exemplary, very different risk scenarios, the given parameter set reproduces 63-74% of the individual risk variability for left-sided breast cancer patients. These anatomic features will be used in the PASSOS software to support decision processes in breast-cancer therapy.
- MeSH
- celková dávka radioterapie MeSH
- kritické orgány účinky záření MeSH
- lidé MeSH
- nádory prsu radioterapie MeSH
- nádory vyvolané zářením etiologie patologie MeSH
- plánování radioterapie pomocí počítače metody MeSH
- plíce patologie účinky záření MeSH
- počítačová rentgenová tomografie metody MeSH
- počítačové zpracování obrazu metody MeSH
- prsy patologie účinky záření MeSH
- radiační poranění etiologie patologie MeSH
- radioterapie s modulovanou intenzitou škodlivé účinky MeSH
- srdce anatomie a histologie účinky záření MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Twenty (10 intensity-modulated proton therapy (IMPT) and 10 intensity-modulated x-ray therapy (IMXT) treatment plans for patients with advanced prostate carcinoma were compared in this study. All chosen patients were indicated for prostate and pelvic lymph nodes irradiation using simultaneous integrated boost technique. These patients represent typical specimen for this diagnose. IMPT irradiates just half of the tissue volume with a low dose (up to 10 cobalt gray equivalent) compared to IMXT without compromise in target volumes coverage and in this way reduces the risk of secondary cancer development or other possible complications.
- MeSH
- celková dávka radioterapie MeSH
- kritické orgány účinky záření MeSH
- lidé MeSH
- lymfatické uzliny účinky záření MeSH
- nádory prostaty radioterapie MeSH
- pánev účinky záření MeSH
- plánování radioterapie pomocí počítače metody MeSH
- protonová terapie metody MeSH
- radioterapie s modulovanou intenzitou metody MeSH
- rentgenová terapie metody MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Introduction: Within an International Atomic Energy Agency (IAEA) co-ordinated research project (CRP), a remote end-to-end dosimetric quality audit for intensity modulated radiation therapy (IMRT)/ volumetric arc therapy (VMAT) was developed to verify the radiotherapy chain including imaging, treatment planning and dose delivery. The methodology as well as the results obtained in a multicentre pilot study and national trial runs conducted in close cooperation with dosimetry audit networks (DANs) of IAEA Member States are presented.Material and methods: A solid polystyrene phantom containing a dosimetry insert with an irregular solid water planning target volume (PTV) and organ at risk (OAR) was designed for this audit. The insert can be preloaded with radiochromic film and four thermoluminescent dosimeters (TLDs). For the audit, radiotherapy centres were asked to scan the phantom, contour the structures, create an IMRT/VMAT treatment plan and irradiate the phantom. The dose prescription was to deliver 4 Gy to the PTV in two fractions and to limit the OAR dose to a maximum of 2.8 Gy. The TLD measured doses and film measured dose distributions were compared with the TPS calculations.Results: Sixteen hospitals from 13 countries and 64 hospitals from 6 countries participated in the multicenter pilot study and in the national runs, respectively. The TLD results for the PTV were all within ±5% acceptance limit for the multicentre pilot study, whereas for national runs, 17 participants failed to meet this criterion. All measured doses in the OAR were below the treatment planning constraint. The film analysis identified seven plans in national runs below the 90% passing rate gamma criteria.Conclusion: The results proved that the methodology of the IMRT/VMAT dosimetric end-to-end audit was feasible for its intended purpose, i.e., the phantom design and materials were suitable; the phantom was easy to use and it was robust enough for shipment. Most importantly the audit methodology was capable of identifying suboptimal IMRT/VMAT delivery.
- MeSH
- celková dávka radioterapie MeSH
- fantomy radiodiagnostické * MeSH
- jaderná energie MeSH
- kritické orgány * MeSH
- lidé MeSH
- mezinárodní agentury MeSH
- pilotní projekty MeSH
- plánování radioterapie pomocí počítače metody MeSH
- počítačová rentgenová tomografie MeSH
- radiometrie metody normy MeSH
- radioterapie s modulovanou intenzitou metody normy MeSH
- revize kvality lékařské péče metody normy MeSH
- studie proveditelnosti MeSH
- zajištění kvality zdravotní péče MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
