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1.
Radiother Oncol ; 158: 97-103, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33636231

RESUMO

PURPOSE/OBJECTIVE: Total body irradiation (TBI) remains a key component of conditioning for allogeneic haemopoietic stem cell transplant (HSCT), with interstitial pneumonitis (IP) and chronic kidney disease (CKD) important late sequelae. We undertook a retrospective service evaluation of TBI patients treated with a forward-planned intensity modulated radiotherapy technique (FP IMRT). MATERIAL/METHODS: 74 adult patients were identified; all received step and shoot FP IMRT TBI, 14.4 Gy in 8 fractions over 4 days. Mean doses to the lungs and kidneys were 12-12.5 Gy. Toxicities were defined as per CTCAE v4.0: IP as multilobar infiltrates on CT with symptoms of dyspnoea, and renal dysfunction as an Estimated Glomerular Filtration rate (eGFR) < 60 ml/min/1.73 m2 for > 3 months. Secondary endpoints were overall survival (OS), progression free survival (PFS), cumulative incidence of non-relapse mortality (NRM), relapse risk and of acute and chronic GvHD. RESULTS: Patients received treatment for the following diagnosis: ALL/LBL (n = 37); AML (n = 33), CML-BC (n = 2) and High grade NHL (n = 2). The rate of IP due to any cause was 30%; positive microbiological evidence in 73% (16 /22). Idiopathic IP was seen in 8%, with only 4% (n = 3) having IP Grade ≥ 3. Two (4%) of 52 long term survivors developed CKD, one with thrombotic microangiopathy. 4 year NRM was 16% (CI 11-32%); no treatment related deaths in matched sibling or umbilical cord blood HSCT. CONCLUSION: FP IMRT TBI, reducing dose to the lungs and kidneys, has lower rates of idiopathic IP and CKD compared to the literature. This technique is safe and effective conditioning for full intensity HSCT.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Doenças Pulmonares Intersticiais , Radioterapia de Intensidade Modulada , Insuficiência Renal Crônica , Adulto , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Incidência , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/etiologia , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Retrospectivos , Condicionamento Pré-Transplante/efeitos adversos , Transplante Homólogo , Irradiação Corporal Total/efeitos adversos
2.
Br J Radiol ; 89(1058): 20150603, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26585543

RESUMO

OBJECTIVE: To determine if subsets of patients may benefit from smaller or larger margins when using laser setup and bony anatomy verification of breast tumour bed (TB) boost radiotherapy (RT). METHODS: Verification imaging data acquired using cone-beam CT, megavoltage CT or two-dimensional kilovoltage imaging on 218 patients were used (1574 images). TB setup errors for laser-only setup (dlaser) and for bony anatomy verification (dbone) were determined using clips implanted into the TB as a gold standard for the TB position. Cases were grouped by centre-, patient- and treatment-related factors, including breast volume, TB position, seroma visibility and surgical technique. Systematic (Σ) and random (σ) TB setup errors were compared between groups, and TB planning target volume margins (MTB) were calculated. RESULTS: For the study population, Σlaser was between 2.8 and 3.4 mm, and Σbone was between 2.2 and 2.6 mm, respectively. Females with larger breasts (p = 0.03), easily visible seroma (p ≤ 0.02) and open surgical technique (p ≤ 0.04) had larger Σlaser. Σbone was larger for females with larger breasts (p = 0.02) and lateral tumours (p = 0.04). Females with medial tumours (p < 0.01) had smaller Σbone. CONCLUSION: If clips are not used, margins should be 8 and 10 mm for bony anatomy verification and laser setup, respectively. Individualization of TB margins may be considered based on breast volume, TB and seroma visibility. ADVANCES IN KNOWLEDGE: Setup accuracy using lasers and bony anatomy is influenced by patient and treatment factors. Some patients may benefit from clip-based image guidance more than others.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Tomografia Computadorizada de Feixe Cônico/métodos , Erros de Configuração em Radioterapia/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Posicionamento do Paciente , Fótons , Interpretação de Imagem Radiográfica Assistida por Computador , Planejamento da Radioterapia Assistida por Computador , Radioterapia Guiada por Imagem , Reino Unido
3.
PLoS One ; 10(9): e0136962, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26325073

RESUMO

INTRODUCTION: The wildlife plague system in the Pre-Balkhash desert of Kazakhstan has been a subject of study for many years. Much progress has been made in generating a method of predicting outbreaks of the disease (infection by the gram negative bacterium Yersinia pestis) but existing methods are not yet accurate enough to inform public health planning. The present study aimed to identify characteristics of individual mammalian host (Rhombomys opimus) burrows related to and potentially predictive of the presence of R.opimus and the dominant flea vectors (Xenopsylla spp.). METHODS: Over four seasons, burrow characteristics, their current occupancy status, and flea and tick burden of the occupants were recorded in the field. A second data set was generated of long term occupancy trends by recording the occupancy status of specific burrows over multiple occasions. Generalised linear mixed models were constructed to identify potential burrow properties predictive of either occupancy or flea burden. RESULTS: At the burrow level, it was identified that a burrow being occupied by Rhombomys, and remaining occupied, were both related to the characteristics of the sediment in which the burrow was constructed. The flea burden of Rhombomys in a burrow was found to be related to the tick burden. Further larger scale properties were also identified as being related to both Rhombomys and flea presence, including latitudinal position and the season. CONCLUSIONS: Therefore, in advancing our current predictions of plague in Kazakhstan, we must consider the landscape at this local level to increase our accuracy in predicting the dynamics of gerbil and flea populations. Furthermore this demonstrates that in other zoonotic systems, it may be useful to consider the distribution and location of suitable habitat for both host and vector species at this fine scale to accurately predict future epizootics.


Assuntos
Animais Selvagens/microbiologia , Reservatórios de Doenças/microbiologia , Peste/microbiologia , Peste/transmissão , Animais , Surtos de Doenças , Vetores de Doenças , Ecossistema , Cazaquistão , Densidade Demográfica , Doenças dos Roedores/microbiologia , Doenças dos Roedores/transmissão , Estações do Ano , Sifonápteros/microbiologia , Xenopsylla/microbiologia , Yersinia pestis/patogenicidade
4.
AIDS Res Treat ; 2015: 740212, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26257954

RESUMO

Adult women (n = 113) and men (n = 100) initiating combination antiretroviral therapy (cART) and women not yet eligible for cART (n = 199) in Kigali, Rwanda, were followed for 6-24 months between 2007 and 2010. In the cART groups, 21% of patients required a drug change due to side effects and 11% of patients had virological failure (defined as >1,000 HIV RNA copies/mL) after 12 months of cART. About a third of the pregnancies since HIV diagnosis were unintended. The proportion of women in the pre-cART group using modern contraception other than condoms (50%) was similar to women in the general population, but this proportion was only 25% in women initiating cART. Of the women who carried at least one pregnancy to term since having been diagnosed HIV-positive, a third reported to have participated in a prevention-of-mother-to-child-transmission (PMTCT, option A) intervention. Many patients were coinfected with herpes simplex virus type 2 (79-92%), human papillomavirus (38-53%), and bacterial sexually transmitted infections (STIs) with no differences between groups. We applaud the Rwandan government for having strengthened family planning and PMTCT services and for having introduced HPV vaccination in recent years, but additional work is needed to strengthen STI and HPV-related cancer screening and management in the HIV-positive population.

5.
J Biogeogr ; 42(7): 1281-1292, 2015 07.
Artigo em Inglês | MEDLINE | ID: mdl-26877580

RESUMO

AIM: The spatial structure of a population can strongly influence the dynamics of infectious diseases, yet rarely is the underlying structure quantified. A case in point is plague, an infectious zoonotic disease caused by the bacterium Yersinia pestis. Plague dynamics within the Central Asian desert plague focus have been extensively modelled in recent years, but always with strong uniformity assumptions about the distribution of its primary reservoir host, the great gerbil (Rhombomys opimus). Yet, while clustering of this species' burrows due to social or ecological processes could have potentially significant effects on model outcomes, there is currently nothing known about the spatial distribution of inhabited burrows. Here, we address this knowledge gap by describing key aspects of the spatial patterns of great gerbil burrows in Kazakhstan. LOCATION: Kazakhstan. METHODS: Burrows were classified as either occupied or empty in 98 squares of four different sizes: 200 m (side length), 250 m, 500 m and 590-1020 m. We used Ripley's K statistic to determine whether and at what scale there was clustering of occupied burrows, and semi-variograms to quantify spatial patterns in occupied burrows at scales of 250 m to 9 km. RESULTS: Significant spatial clustering of occupied burrows occurred in 25% and 75% of squares of 500 m and 590-1020 m, respectively, but not in smaller squares. In clustered squares, the clustering criterion peaked around 250 m. Semi-variograms showed that burrow density was auto-correlated up to a distance of 7 km and occupied density up to 2.5 km. MAIN CONCLUSIONS: These results demonstrate that there is statistically significant spatial clustering of occupied burrows and that the uniformity assumptions of previous plague models should be reconsidered to assess its significance for plague transmission. This field evidence will allow for more realistic approaches to disease ecology models for both this system and for other structured host populations.

7.
Radiother Oncol ; 93(3): 424-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19854526

RESUMO

INTRODUCTION: One method to overcome the problem of lung tumour movement in patients treated with radiotherapy is to restrict tumour motion with an active breathing control (ABC) device. This study evaluated the feasibility of using ABC in patients receiving radical radiotherapy for non-small cell lung cancer. METHODS: Eighteen patients, median (range) age of 66 (44-82) years, consented to the study. A training session was conducted to establish the patient's breath hold level and breath hold time. Three planning scans were acquired using the ABC device. Reproducibility of breath hold was assessed by comparing lung volumes measured from the planning scans and the volume recorded by ABC. Patients were treated with a 3-field coplanar beam arrangement and treatment time (patient on and off the bed) and number of breath holds recorded. The tolerability of the device was assessed by weekly questionnaire. Quality assurance was performed on the two ABC devices used. RESULTS: 17/18 patients completed 32 fractions of radiotherapy using ABC. All patients tolerated a maximum breath hold time >15s. The mean (SD) patient training time was 13.8 (4.8)min and no patient found the ABC very uncomfortable. Six to thirteen breath holds of 10-14 s were required per session. The mean treatment time was 15.8 min (5.8 min). The breath hold volumes were reproducible during treatment and also between the two ABC devices. CONCLUSION: The use of ABC in patients receiving radical radiotherapy for NSCLC is feasible. It was not possible to predict a patient's ability to hold breath. A minimum tolerated breath hold time of 15 s is recommended prior to commencing treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Respiração , Técnicas de Imagem de Sincronização Respiratória/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Movimento , Tomografia Computadorizada por Raios X
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