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41.
AimTo evaluate patient choice of prostate cancer radiotherapy fractionation, using a decision aid.BackgroundRecent ASTRO guidelines recommend patients with localised prostate cancer be offered moderately hypofractionated radiation therapy after discussing increased acute toxicity and uncertainty of long-term results compared to conventional fractionation.Materials and methodsA decision aid was designed to outline the benefits and potential downsides of conventionally and moderately hypofractionated radiation therapy. The aid incorporated the ASTRO guideline to outline risks and benefits.ResultsIn all, 124 patients with localised prostate cancer were seen from June-December 2018. Median age was 72 (range 50–90), 49.6 % were intermediate risk (50.4 % high risk). All except three patients made a choice using the aid; the three undecided patients were hypofractionated. In all, 33.9 % of patients chose hypofractionation: falling to 25.3 % for patients under 75 years, 24.3 % for patients living within 30 miles of the cancer centre, and 14.3 % for patients with baseline gastrointestinal symptoms. On multivariate analysis, younger age, proximity to the centre, and having baseline gastrointestinal symptoms significantly predicted for choosing conventional fractionation. Insurance status, attending clinician, baseline genitourinary symptoms, work/carer status, ECOG, cancer risk group and driving status did not impact choice. Reasons for choosing conventional fractionation were certainty of long-term results (84 %) and lower acute bowel toxicity (51 %).ConclusionsMost patients declined the convenience of moderate hypofractionation due to potentially increased acute toxicity, and the uncertainty of long-term outcomes. We advocate that no patient should be offered hypofractionation without a thorough discussion of uncertainty and acute toxicity.  相似文献   
42.
PurposeReport our matured outcomes of European nasopharyngeal carcinoma (NPC) treatment from a non-endemic region in the IMRT era.MethodsWe reviewed 109 consecutive patients with biopsy proven NPC treated between 2009 and 2013. All received IMRT as per RTOG 0615. Toxicity was scored accordingly to CTCAE 4.03. Platinum-based chemotherapy was delivered following the Intergroup 0099.ResultsMedian age of 53 years; 97% Caucasian; 74% male; 72% WHO grade III; 43% T1; 14% T2; 18% T3, 25% T4; 17% N0; 17% N1; 39% N2; 27% N3. Compliance to adjuvant chemotherapy was 88%. With a median follow up of 56 months, the 4-year local control was 90.2% (88.6% for T1; 100% for T2; 85% for T3; and 91.7% for T4), the 4-year distant metastases-free survival was 86% and an overall survival rate was 77%. Local control and survival were better in G3 (p < 0.001 and p = 0.032, respectively). Xerostomia was the most frequent late toxicity in 55% (n = 60). Hypothyroidism requiring hormonal reposition occurred in 15.5% (n = 17). From the 36 deaths, 20 were due to distant metastases, 3 grade 5 toxicity, 2 from local progression, 5 non-cancer deaths and unknown cause in the remaining 6. On multivariable analysis, age (p = 0.017), local recurrence and distant metastases were associated with death (p < 0.001, both).ConclusionOur matured data from the IMRT era showed a major improvement from our 3D cohort series reaching excellent local and regional control, even in T4. Local recurrences, despite few, and distant metastases were correlated with the risk of death.  相似文献   
43.
PurposeRestricted studies comparing different dose rate parameters are available while ITV-based VMAT lung SBRT planning leads to perform the analysis of the most suitable parameters of the external beams used. The special emphasis was placed on the impact of dose rate on dose distribution variations in target volumes due to interplay effects.MethodsFour VMAT plans were calculated for 15 lung tumours using 6 MV photon beam quality (flattening filter FF vs. flattening filter free FFF beams) and maximum dose rate of 600 MU/min, 1000 MU/min and 1400 MU/min. Three kinds of motion simulations were performed finally giving 180 plans with perturbed dose distributions.Results6FFF-1400 MUs/min plans were characterized by the shortest beam on time (1.8 ± 0.2 min). Analysing the performed motion simulation results, the mean dose (Dmean) is not a sensitive parameter to related interplay effects. Looking for local maximum and local minimum doses, some discrepancies were found, but their significance was presented for individual patients, not for the whole cohort. The same was observed for other verified dose metrics.ConclusionsGenerally, the evaluation of VMAT robustness between FF and FFF concepts against interplay effect showed a negligible effect of simulated motion influence on tumour coverage among different photon beam quality parameters. Due to the lack of FFF beams, smaller radiotherapy centres are able to perform ITV-based VMAT lung SBRT treatment in a safe way. Radiotherapy department having FFF beams could perform safe, fast and efficient ITV-based VMAT lung SBRT without a concern about significance of interplay effects.  相似文献   
44.
AimThe aim of this study was to compare the outcomes, patterns of failure and laryngeal preservation rates in patients with T1N0 glottic cancer treated with surgery or radiotherapy.Materials/methodsRetrospective study of T1N0 glottic cancer patients treated in our institution between January 2007 and December 2017. Histologically proven squamous cell carcinoma patients, treated with upfront cordectomy/partial laryngectomy (S group) or radiotherapy (RT group) were included. Elective treatment of the neck was not permitted. Local failure (LF), disease-free survival (DFS), ultimate disease-free survival (UDFS), laryngectomy-free survival (LFS), disease-specific mortality (DSM) and overall survival (OS) were evaluated.ResultsTwo hundred and one patients were eligible (172 S group, 29 RT group), with a median follow-up of 38.8 months. Overall, 33 (16%) patients had a recurrence, 30 (17%) in the S group and 3 (10%) in the RT group. Local failure was the predominant site of failure (28 S, 2 RT). Overall, of all those that were salvaged, 17 (8%) underwent total laryngectomy (15 S, 2 RT). There was no significant difference in the 5-year cumulative incidence of LF (20.8% S, 8.1% RT, p = 0.138), 5-y LFS (85.0% vs. 91.7%, p = 0.809), 5-y DFS (67.5% vs. 82.1%, p = 0.343), 5-y UDFS (82.5% vs. 90.3%, p = 0.647) and 5-y OS (84.5% vs. 90.3%, p = 0.892). Multivariate analysis showed no correlation between initial treatment and the analyzed outcomes.ConclusionPrimary surgery or radiotherapy were similar first line options, since they do not differ in all outcomes. Patients’ and physician's preferences must be considered when choosing first treatment.  相似文献   
45.
AimWe conducted a study to validate the MDASI-HN based nomogram, which is used to predict the acute toxicities in head and neck cancer patients undergoing radiation therapy with or without chemotherapy.BackgroundTolerance to radiation varies from patient to patient and also depends on various other factors like tumor volume, dose of radiation, chemotherapy. Predicting the toxicities allow us to identify potential candidates who are likely to have a higher toxicity and, in addition, evaluates the nomogram when done on an independent group of patients.Materials and MethodsSixty biopsy confirmed head and neck cancer patients undergoing radiation were the subjects of the study. The patients completed patient reported outcome instrument (PRO) MDASI-HN questionnaire at the beginning and at the fifth week of radiation. The baseline score obtained was used to obtain the predicted score using nomogram. The nomogram was also externally validated as per the TRIPOD guidelines.ResultsThe mean baseline, predicted and score at the fifth week were 27.28 ± 11.04, 73.33 ± 15.51 and 82.62 ± 17.67, respectively, for all sub-sites. A positive, significant correlation (p < 0.01) between the predicted score and the score at the fifth week was seen across all sub sites such as Oral cavity (p = 0.05), Oropharynx (p = 0.02), Hypo pharynx (p = 0.02) and Larynx (p = 0.02).ConclusionThe MDASI-HN questionnaire based nomogram is simple, easily doable and takes into consideration the initial symptoms as well the treatment details; thereby, it is able to predict the toxicities accurately.  相似文献   
46.
AimTo provide recommendations for the management of patients with cancer in the COVID-19 era.BackgroundThe current global pandemic of COVID-19 has severely impacted global healthcare systems. Several groups of people are considered high-risk for SARS-CoV-2 infection, including patients with cancer. Therefore, protocols for the better management of these patients during this viral pandemic are necessary. So far, several protocols have been presented regarding the management of patients with cancer during the COVID-19 pandemic. However, none of them points to a developing country with limited logistics and facilities.MethodsIn this review, we have provided a summary of recommendations on the management of patients with cancer during the COVID-19 pandemic based on our experience in Shohada-e Tajrish Hospital, Iran.ResultsWe recommend that patients with cancer should be managed in an individualized manner during the COVID-19 pandemic.ConclusionsOur recommendation provides a guide for oncology centers of developing countries for better management of cancer.  相似文献   
47.
PurposeTo define a method and investigate how the adjustment of scan parameters affected the image quality and Hounsfield units (HUs) on a CT scanner used for radiotherapy treatment planning. A lack of similar investigations in the literature may be a contributing factor in the apparent reluctance to optimise radiotherapy CT protocols.MethodA Catphan phantom was used to assess how image quality on a Toshiba Aquilion LB scanner changed with scan parameters. Acquisition and reconstruction field-of-view (FOV), collimation, image slice thickness, effective mAs per rotation and reconstruction algorithm were varied. Changes were assessed for HUs of different materials, high contrast spatial resolution (HCSR), contrast-noise ratio (CNR), HU uniformity, scan direction low contrast and CT dose-index.ResultsCNR and HCSR varied most with reconstruction algorithm, reconstruction FOV and effective mAs. Collimation, but not image slice width, had a significant effect on CT dose-index with narrower collimation giving higher doses. Dose increased with effective mAs. Highest HU differences were seen when changing reconstruction algorithm: 56 HU for densities close to water and 117 HU for bone-like materials. Acquisition FOV affected the HUs but reconstruction FOV and effective mAs did not.ConclusionsAll the scan parameters investigated affected the image quality metrics. Reconstruction algorithm, reconstruction FOV, collimation and effective mAs were most important. Reconstruction algorithm and acquisition FOV had significant effect on HU. The methodology is applicable to radiotherapy CT scanners when investigating image quality optimisation, prior to assessing the impact of scan protocol changes on clinical CT images and treatment plans.  相似文献   
48.
目的:观察保乳手术联合放射治疗乳腺癌患者临床疗效。方法:选取我院收治的乳腺癌患者84例,均采取保乳手术联合放射治疗,观察临床疗效。结果:所有患者手术均获得成功,84例乳腺癌患者均在出院后进行随访,平均随访时间(2.1±0.4)年,各项检查未发现复发迹象。在放疗的期间内,乳房出现刺痛、发痒的不适患者20例,皮肤色素沉着、红斑的患者37例,在治疗后发生湿性脱皮患者10例,放射性食管炎患者8例;在放疗结束1个月,出现反射性肺炎患者2例。手术及放疗后,患者乳房的美容效果中优秀患者49例,良好患者29例,较差患者6例;行肿瘤扩大切除术患者优秀率高于行象限切除术患者,差异有统计学意义(P0.05)。结论:保乳手术联合放疗可保证治疗效果,同时降低并发症的发生,有利于美观,是一种优秀的乳腺癌治疗方法。  相似文献   
49.

Background

Radiation technology is a discipline of medical science which deals with diagnostics, imaging and radiotherapy, that is treatment by ionizing radiation.

Aim

To present and compare the existing curricula of radiation technology in selected EU countries.

Materials and methods

The research work done for the purpose of the comparative analysis was based on the methods of diagnostic test and document analysis.

Results

The comparison of curricula in selected countries, namely Austria, France, the Netherlands and Poland, showed that admission criteria to radiation technology courses are varied and depend on regulations of respective Ministries of Health. The most restrictive conditions, including written tests in biology, chemistry and physics, and psychometric test, are those in France. Contents of basic and specialist subject groups are very similar in all the countries. The difference is in the number of ECT points assigned to particular subjects and the number of course hours offered. The longest practical training is provided in the Netherlands and the shortest one in Poland. The duration of studies in the Netherlands is 4 years, while in Poland it is 3 years. Austria is the only country to offer extra practical training in quality management.

Conclusion

Graduates in the compared EU countries have similar level of qualifications in the fields of operation of radiological equipment, radiotherapy, nuclear medicine, foreign language and specialist terminology in the field of medical and physical sciences, general knowledge of medical and physical sciences, and detailed knowledge of radiation technology.  相似文献   
50.
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