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1.
J Appl Clin Med Phys ; 22(5): 69-78, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33942952

RESUMO

PURPOSE: The aim of this study was to verify the possibility of summing the dose distributions of combined radiotherapeutic treatment of cervical cancer using the extended Lucas-Kanade algorithm for deformable image registration. MATERIALS AND METHODS: First, a deformable registration of planning computed tomography images for the external radiotherapy and brachytherapy treatment of 10 patients with different parameter settings of the Lucas-Kanade algorithm was performed. By evaluating the registered data using landmarks distance, root mean square error of Hounsfield units and 2D gamma analysis, the optimal parameter values were found. Next, with another group of 10 patients, the accuracy of the dose mapping of the optimized Lucas-Kanade algorithm was assessed and compared with Horn-Schunck and modified Demons algorithms using dose differences at landmarks. RESULTS: The best results of the Lucas-Kanade deformable registration were achieved for two pyramid levels in combination with a window size of 3 voxels. With this registration setting, the average landmarks distance was 2.35 mm, the RMSE was the smallest and the average gamma score reached a value of 86.7%. The mean dose difference at the landmarks after mapping the external radiotherapy and brachytherapy dose distributions was 1.33 Gy. A statistically significant difference was observed on comparing the Lucas-Kanade method with the Horn-Schunck and Demons algorithms, where after the deformable registration, the average difference in dose was 1.60 Gy (P-value: 0.0055) and 1.69 Gy (P-value: 0.0012), respectively. CONCLUSION: Lucas-Kanade deformable registration can lead to a more accurate model of dose accumulation and provide a more realistic idea of the dose distribution.


Assuntos
Braquiterapia , Neoplasias do Colo do Útero , Algoritmos , Feminino , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia
2.
J Contemp Brachytherapy ; 12(2): 118-123, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32395135

RESUMO

PURPOSE: The purpose of this study was to evaluate the influence of 3D brachytherapy planning time on the real dose distribution. MATERIAL AND METHODS: 10 patients with cervical cancer were evaluated using 2 computed tomography (CT) scans brachytherapy. The first scan was performed after the insertion of UVAG applicators, and the second was done after creating the treatment plan, just before the irradiation of first and third fraction. Both plans were compared in terms of changes of volumes and differences in the dose for high-risk organs using GEC-ESTRO Working Group parameters. RESULTS: The median planning time was 54 minutes (36-64 minutes). The absolute median change of volume for bladder, rectum, and sigmoid was 32.1 cm3 (1.6-108.6 cm3), 5.6 cm3 (0.4-61.8 cm3), and 8.4 cm3 (0.2-74.1 cm3), respectively. This difference led to an increased dose for bladder and sigmoid for D0.1cc by 46.7 cGy and 25.7 cGy, for D1cc by 59.2 cGy and 11.8 cGy, and for D2cc by 44.7 cGy and 10 cGy, respectively, per each fraction. Measured volume change in case of rectum led to a decreased dose per each fraction for D0.1cc with 7.1 cGy, for D1cc with 3.5 cGy, and for D2cc with 4.8 cGy. We observed that statistically significant dependency between the planning time and the dose was proved for rectum. The longer time for planning, the higher dose for rectum. The correlation coefficient for D0.1cc was 0.6715 (p = 0.0061), for D1cc was 0.6404 (p = 0.011), and for D2cc was 0.5891 (p = 0.0197). CONCLUSIONS: Extended treatment planning time for brachytherapy due to the changes in topography of small pelvis can lead to different dose in high-risk organs than previously planned. It seems that the most significant changes are related to rectum.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31602046

RESUMO

AIMS: The purpose of this study was to compare the treatment times for deep-inspiration breath hold with and without audio-visual (A-V) navigation. METHODS: We measured the real treatment time in 60 patients with breast cancer undergoing postoperative radiotherapy. Thirty consecutive patients were treated without deep-inspiration breath hold (DIBH) and another 30 patients using deep-inspiration breath hold (10 patients with DIBH only, 10 patients with DIBH using visual feedback and 10 patients with DIBH using visual feedback following breath training). The treatment time was relativized to number of fields and 100 monitor units (MU). The independent t-test was used to analyse differences between cohorts. RESULTS: The mean treatment time for patients without DIBH was 46.5 seconds per field and 90.9 seconds per 100 MU, for DIBH only 92.3 and 170.2 seconds, for DIBH with audio-visual navigation 68.1 and 133.8 seconds, and for DIBH with A-V feedback including breath training 66.1 and 132.5 seconds. The treatment times for patients treated using DIBH with visual navigation were significantly shorter in comparison with patients without visual feedback. We were not able to prove any significant benefit for breath training in terms of reducing the treatment time. CONCLUSION: Audio-visual navigation enables to significantly reduce the treatment time in comparison with DIBH without A-V feedback.


Assuntos
Neoplasias da Mama/radioterapia , Suspensão da Respiração , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
4.
Oncol Lett ; 13(3): 1807-1810, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28454327

RESUMO

Esophageal cancer (EC) consists of tumors with a generally poor prognosis, and treatment options for patients with disease recurrence are extremely limited. Due to this poor patient prognosis, the possible treatment toxicity should be carefully balanced against its potential benefit and patient quality of life. Stereotactic body radiotherapy (SBRT) is a rapidly expanding novel technique combining a short treatment time together with high local efficacy and an acceptable toxicity profile. There are no publications thus far presenting data regarding the usage of SBRT utilizing a conventional linear accelerator in locally recurrent EC patients. In the present study, 2 patients with recurrent EC in the neck lymph nodes were treated by SBRT in the Department of Oncology, University Hospital Olomouc, Czech Republic. The treatment dose was 30 and 40 Gy in 5 daily fractions, with a prescribed dose to 65 and 81% isodose, for each patient respectively, utilizing a volumetric arc therapy technique, a 6-MV photon beam and an Elekta Synergy linear accelerator. The treatment was delivered without any unintentional treatment interruptions and without any treatment-related acute toxicity. The maximum dose in the patients was 45.9 and 49.2 Gy, respectively. The maximum doses for the surrounding major blood vessels were 35.4 and 45.7 Gy, respectively. Maximum doses to the trachea and the esophagus in the first patient were 32.6 and 27.0 Gy. In the second patient, these doses were not clinically significant. SBRT utilizing linear accelerators should be considered in patients with localized recurrent EC, offering the patients the chance for local control with minimal treatment toxicity.

5.
PLoS One ; 12(1): e0169308, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28072839

RESUMO

OBJECTIVE: The aim of this study was to examine the potential association between intrauterine exposure to maternal diabetes and attention deficits in the offspring. RESEARCH DESIGN AND METHODS: Adolescent offspring of a prospectively followed cohort of women with type 1 diabetes (n = 269) and a control group from the background population (n = 293) participated in a follow-up assessment in 2012-2013. We used scores from Conners Continuous Performance Test II to assess attention and based on a principal component analysis we evaluated scores on five different attention factors: focused attention, vigilance, hyperactivity/impulsivity, sustained attention and response style. RESULTS: A higher frequency of the exposed offspring had a parent/self-reported use of Attention Deficit Hyperactivity Disorder (ADHD) medication compared to the control group (2.2% vs. 0.0%, p = 0.01). Clinical significant differences between adolescents exposed to maternal diabetes and unexposed controls were not found in either single scores on Conners Continuous Performance Test or on any of the five attention factors identified. CONCLUSIONS: Exposure to maternal type 1 diabetes did not seem to increase the risk of attention deficits in the adolescent offspring. However, a higher self-reported use of ADHD medication in the exposed group could suggest a difference in attention not revealed by the applied test.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Gestacional , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Adolescente , Adulto , Atenção , Dinamarca , Feminino , Seguimentos , Humanos , Masculino , Gravidez , Fatores de Risco , Adulto Jovem
6.
Anticancer Res ; 36(12): 6641-6646, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27919996

RESUMO

BACKGROUND: The management of internal mammary nodes (IMNs) during multidisciplinary treatment of breast cancer has been debated for the last four decades without unequivocal conclusion. PATIENTS AND METHODS: We retrospectively reviewed patients with breast cancer who underwent sentinel lymph node biopsy at our center from 2008 until 2012. IMN drainage was assessed as a potential risk factor for local and distant disease recurrence. RESULTS: We identified 712 patients, with incidence of drainage to IMNs of 18.4%. No detrimental effect of the pattern of drainage to IMNs was found after a median follow-up of 58 months. A similar outcome was observed when drainage to IMNs was evaluated as a risk factor for patient survival. The potential risk factors for drainage to IMNs during sentinel lymph node biopsy were younger age (p=0.002) and tumor location in lower-outer, lower-inner, and upper-inner versus upper-outer quadrant (p<0.0001). CONCLUSION: The drainage to IMNs is unlikely to have a detrimental effect on patient outcome.


Assuntos
Neoplasias da Mama/patologia , Linfonodos/patologia , Drenagem , Humanos , Metástase Linfática , Metástase Neoplásica , Prognóstico
7.
Artigo em Inglês | MEDLINE | ID: mdl-27641139

RESUMO

BACKGROUND AND AIMS: As treatments for primary cancers continue to improve life expectancy, unfortunately, brain metastases also appear to be constantly increasing and life expectancy for patients with brain metastases is low. Longer survival and improved quality of life may be achieved using localised radiological and surgical approaches in addition to low dose corticosteroids. Stereotactic brain radiotherapy is one rapidly evolving localized radiation treatment. This article describes our experience with stereotactic radiotherapy using a linear accelerator. METHODS: We reviewed patients treated with stereotactic radiotherapy, from the time of its introduction into daily practice in our Department of Oncology in 2014. We collected the data on patient treatment and predicted survival based on prognostic indices and actual patient outcome. RESULTS: A total of 10 patients were treated by stereotactic radiotherapy, in one case in combination with whole brain radiotherapy and hippocampal sparing. There was no significant treatment related toxicity during the treatment or follow-up and due to the small number of fractions, the overall tolerance of the treatment was excellent. The patient intrafractional movement in all cases was under 1 mm suggesting that 1 mm margin around the CTV to create the PTV is sufficient and also that patient immobilization using the thermoplastic mask compared with invasive techniques, is feasible. We also found that prognostic indices such as the Graded Prognostic Assessment provide accurate predictions of patient survival. CONCLUSIONS: Based on our current evidence, patients with brain metastases fit enough, should be considered for stereotactic radiotherapy treatment.


Assuntos
Neoplasias Encefálicas/radioterapia , Radiocirurgia/instrumentação , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceleradores de Partículas , Radiocirurgia/mortalidade , Estudos Retrospectivos , Resultado do Tratamento
8.
Oncol Lett ; 11(6): 3777-3781, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27313693

RESUMO

Renal cell cancer patients with brain metastatic disease generally have poor prognosis. Treatment options include surgery, radiotherapy, targeted therapy or best supportive care with respect to disease burden, patient preference and performance status. In the present case report the radiotherapy technique combining whole brain radiotherapy with hippocampal sparing (hippocampal avoidance whole brain radiotherapy HA-WBRT) and hypofractionated stereotactic radiotherapy (SRT) of the brain metastases is performed in a patient with metastatic renal cell carcinoma. HA-WBRT was administered to 30 Gy in 10 fractions with sparing of the hippocampal structures and SRT of 21 Gy in 3 fractions to brain metastases which has preceded the HA-WBRT. Two single arc volumetric modulated arc radiotherapy (VMAT) plans were prepared using Monaco planning software. The HA-WBRT treatment plan achieved the following results: D2=33.91 Gy, D98=25.20 Gy, D100=14.18 Gy, D50=31.26 Gy. The homogeneity index was calculated as a deduction of the minimum dose in 2% and 98% of the planning target volume (PTV), divided by the minimum dose in 50% of the PTV. The maximum dose to the hippocampus was 17.50 Gy and mean dose was 11.59 Gy. The following doses to organs at risk (OAR) were achieved: Right opticus Dmax, 31.96 Gy; left opticus Dmax, 30.96 Gy; chiasma D max, 32,76 Gy. The volume of PTV for stereotactic radiotherapy was 3,736 cm3, with coverage D100=20.95 Gy and with only 0.11% of the PTV being irradiated to dose below the prescribed dose. HA-WBRT with SRT represents a feasible technique for radiotherapy of brain metastatic disease, however this technique is considerably demanding on departmental equipment and staff time/experience.

9.
Diabetes Care ; 39(8): 1356-63, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27271191

RESUMO

OBJECTIVE: Exposure to maternal diabetes in utero may have a negative impact on the developing brain. The objective was to examine long-term cognitive consequences of intrauterine hyperglycemia in adolescent offspring of women with type 1 diabetes and to ascertain a possible association with maternal HbA1c. RESEARCH DESIGN AND METHODS: Offspring of a prospectively followed cohort of women with type 1 diabetes (n = 277) participated in a follow-up examination at the age of 13-19 years. A control group from the background population was identified (n = 301). Cognitive function was evaluated using Reynolds Intellectual Assessment Scales and classified into indices of composite intelligence, verbal and nonverbal intelligence, and composite memory. Frequencies of reading and writing problems and attendance to classes for children with learning difficulties were assessed. RESULTS: Offspring of women with type 1 diabetes scored lower in all normalized and standardized intelligence indices compared with controls: composite intelligence (95.7 vs. 100, P = 0.001), verbal intelligence (96.2 vs. 100, P = 0.004), nonverbal intelligence (96.4 vs. 100, P = 0.008), and composite memory (95.7 vs. 100, P = 0.001). A higher frequency of diabetes-exposed offspring had parent-reported learning difficulties in primary school. Differences between groups remained after adjustment for confounders and potential mediators. We found no direct association between maternal HbA1c and offspring cognitive function in the exposed group. CONCLUSIONS: Adolescent offspring of women with type 1 diabetes had lower cognitive function compared with a control group, also after adjustment for confounders and potential mediators. These differences may reflect direct harmful effects of maternal diabetes on neurodevelopment in the offspring.


Assuntos
Cognição , Disfunção Cognitiva/diagnóstico , Diabetes Mellitus Tipo 1/sangue , Hiperglicemia/sangue , Gravidez em Diabéticas/sangue , Efeitos Tardios da Exposição Pré-Natal/diagnóstico , Adolescente , Glicemia/metabolismo , Disfunção Cognitiva/sangue , Feminino , Seguimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Hiperglicemia/diagnóstico , Modelos Lineares , Modelos Logísticos , Masculino , Análise Multivariada , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Estudos Prospectivos , Instituições Acadêmicas , Adulto Jovem
11.
Diabetes Care ; 38(7): 1238-44, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26070588

RESUMO

OBJECTIVE: This study examined the effect of maternal pregestational type 1 diabetes on offspring primary school performance. RESEARCH DESIGN AND METHODS: We performed a prospective combined clinical and register-based cohort study comparing primary school performance in offspring (n = 707) of women with pregestational type 1 diabetes with matched control offspring (n = 60,341). We also examined the association between HbA1c levels during pregnancy and later school performance among offspring born to women with pregestational type 1 diabetes. RESULTS: Offspring of mothers with pregestational type 1 diabetes obtained similar school grades as control offspring when finishing primary school (regression coefficient [ß] = -0.13; 95% CI = -0.30 to 0.03; P = 0.12). Adjusting for parental education also resulted in an insignificant difference between the two groups (ß = -0.07; 95% CI = -0.23 to 0.09; P = 0.37). Among offspring of women with type 1 diabetes, increasing maternal HbA1c pregestationally and throughout the pregnancy was associated with lower average school grades. Offspring born to mothers with good glycemic control in the third trimester obtained higher average school grades compared with control offspring. The opposite applied to offspring born to mothers with inadequate glycemic control, who obtained significantly lower average school grades compared with control offspring. CONCLUSIONS: Offspring of mothers with pregestational type 1 diabetes obtained similar average grades when finishing primary school compared with matched control offspring. Among offspring of women with type 1 diabetes, we found a consistent negative association between maternal HbA1c in pregnancy and primary school grades. However, whether this association reflects a direct causal influence of intrauterine hyperglycemia is uncertain.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Gestacional , Hiperglicemia , Inteligência/fisiologia , Efeitos Tardios da Exposição Pré-Natal/psicologia , Adulto , Glicemia/metabolismo , Estudos de Casos e Controles , Criança , Escolaridade , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Mães , Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Instituições Acadêmicas
12.
Diabetologia ; 58(7): 1454-63, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25924986

RESUMO

AIMS/HYPOTHESIS: We aimed to investigate metabolic risk factors, insulin sensitivity and insulin secretion in adolescent offspring of mothers with type 1 diabetes compared with offspring of non-diabetic mothers. METHODS: During 1993-1999, pregnancies of women with type 1 diabetes in Denmark were prospectively reported to a central registry in the Danish Diabetes Association. Data included information on maternal demography, diabetes status and pregnancy outcome. We invited 746 eligible children from this cohort (index offspring) to a follow-up examination. Control offspring were identified through The Danish Central Office of Civil Registration and matched with respect to date of birth, sex and postal code. Anthropometric measurements and blood sampling for metabolic characterisation, including an oral glucose tolerance test, were performed. RESULTS: We examined 278 index offspring (mean age 16.7 years; range 13.0-19.8 years) and 303 control offspring (mean age 16.8 years; range 13.5-20.4 years). Index offspring had higher BMI SD score (0.44: 95% CI 0.21, 0.66) compared with controls, after adjustments for pubertal development and maternal pre-pregnancy BMI. Furthermore, index offspring had a higher prevalence of components included in metabolic syndrome and prediabetes (impaired fasting glucose and/or impaired glucose tolerance), with reduced insulin sensitivity and relative insulin secretion deficiency, compared with controls. Maternal HbA1c levels in pregnancy were not directly associated with offspring metabolic outcomes. CONCLUSIONS/INTERPRETATION: Adolescent offspring of mothers with type 1 diabetes had a less favourable metabolic profile and higher frequency of prediabetes than the background population. Significant associations between these outcomes and maternal HbA1c levels in pregnancy could not be demonstrated. TRIAL REGISTRATION: ClinicalTrials.gov NCT01559181.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Doenças Metabólicas/epidemiologia , Adolescente , Adulto , Antropometria , Dinamarca/epidemiologia , Feminino , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/análise , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Mães , Gravidez , Resultado da Gravidez , Gravidez em Diabéticas , Fatores de Risco , População Branca , Adulto Jovem
13.
Diabetes Care ; 38(5): 821-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25710920

RESUMO

OBJECTIVE: This study examined the long-term consequences for offspring born to mothers with pregestational type 1 diabetes regarding mortality, hospital admissions, and medication. We also examined the association between HbA1c levels during pregnancy and mortality and incidence of hospital admissions. RESEARCH DESIGN AND METHODS: We performed a prospective combined clinical and register-based cohort study comparing mortality, hospital admissions, and use of medication in offspring (n = 1,326) of women with pregestational type 1 diabetes (index children) with matched control subjects (n = 131,884). We also examined the association between HbA1c levels during pregnancy and mortality and the incidence of hospital admissions. Participants were monitored from birth to the age of 13-21 years. RESULTS: Overall mortality was significantly increased for index children (hazard ratio 2.10, 95% CI 1.33-3.30, P = 0.001). The incidence of hospital admissions for index children was significantly increased (incidence rate ratio [IRR] 1.45, 95% CI 1.38-1.53, P < 0.001), and this was the case for all age groups until the age of 15 years. The incidence of hospital admissions among index children was positively associated with maternal HbA1c before pregnancy and in the first trimester. In addition, the overall use of medication was increased in index children (IRR 1.13, 95% CI 1.07-1.19, P < 0.001). CONCLUSIONS: Type 1 diabetes during pregnancy has long-term implications on the health of offspring, with increased mortality, incidence of hospital admissions, and use of medication. Among mothers with type 1 diabetes, glycemic regulation is positively associated with incidence of hospital admissions in offspring.


Assuntos
Diabetes Mellitus Tipo 1/mortalidade , Efeitos Tardios da Exposição Pré-Natal/mortalidade , Adolescente , Adulto , Glicemia/metabolismo , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Hemoglobinas Glicadas/metabolismo , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Lactente , Recém-Nascido , Mães , Gravidez , Estudos Prospectivos , Adulto Jovem
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