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1.
Lancet Oncol ; 22(9): e391-e399, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34478675

RESUMEN

The number of patients with cancer in Africa has been predicted to increase from 844 279 in 2012 to more than 1·5 million in 2030. However, many countries in Africa still lack access to radiotherapy as a part of comprehensive cancer care. The objective of this analysis is to present an updated overview of radiotherapy resources in Africa and to analyse the gaps and needs of the continent for 2030 in the context of the UN Sustainable Development Goals. Data from 54 African countries on teletherapy megavoltage units and brachytherapy afterloaders were extracted from the Directory for Radiotherapy Centres, an electronic, centralised, and continuously updated database of radiotherapy centres. Cancer incidence and future predictions were taken from the GLOBOCAN 2018 database of the International Agency for Research on Cancer. Radiotherapy need was estimated using a 64% radiotherapy utilisation rate, while assuming a machine throughput of 500 patients per year. As of March, 2020, 28 (52%) of 54 countries had access to external beam radiotherapy, 21 (39%) had brachytherapy capacity, and no country had a capacity that matched the estimated treatment need. Median income was an important predictor of the availability of megavoltage machines: US$1883 (IQR 914-3269) in countries without any machines versus $4485 (3079-12480) in countries with at least one megavoltage machine (p=0·0003). If radiotherapy expansion continues at the rate observed over the past 7 years, it is unlikely that the continent will meet its radiotherapy needs. This access gap might impact the ability to achieve the Sustainable Development Goals, particularly the target to reduce preventable, premature mortality by a third, and meet the target of the cervical cancer elimination strategy of 90% with access to treatment. Urgent, novel initiatives in financing and human capacity building are needed to change the trajectory and provide comprehensive cancer care to patients in Africa in the next decade.


Asunto(s)
Recursos en Salud/tendencias , Necesidades y Demandas de Servicios de Salud/tendencias , Radioterapia/tendencias , África/epidemiología , Predicción , Recursos en Salud/estadística & datos numéricos , Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Humanos , Agencias Internacionales , Neoplasias/epidemiología , Neoplasias/radioterapia , Radioterapia/estadística & datos numéricos , Desarrollo Sostenible
2.
Lancet Oncol ; 18(10): e587-e594, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28971825

RESUMEN

During the past six decades, the International Atomic Energy Agency (IAEA) has helped to address the growing cancer burden, by delivering substantial cancer-related assistance to low-income and middle-income member states. IAEA assistance has primarily been facilitated through sustainable radiotherapy and nuclear medicine programmes to establish safe and effective diagnostic imaging, nuclear medicine, and radiotherapy capacity to safely treat patients with cancer. Planning of a National Cancer Control Programme starts with a needs assessment of all aspects of cancer control in the country to ensure evidence-based strategies are adapted to the country's specific needs. The IAEA offers its member states a tool, known as an integrated mission of Programme of Action for Cancer Therapy Review, to assess the status of national capacities for implementation and delivery of cancer control plans and activities and the readiness to develop and implement a long-term radiation medicine infrastructure and plan to improve capacity.


Asunto(s)
Agencias Internacionales/organización & administración , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Energía Nuclear , Oncología por Radiación/organización & administración , Países en Desarrollo , Femenino , Planificación en Salud/organización & administración , Humanos , Masculino , Evaluación de Necesidades , Medicina Nuclear , Perú , Medición de Riesgo , Rol
3.
Strahlenther Onkol ; 190(10): 891-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24715241

RESUMEN

BACKGROUND OR PURPOSE: A joint analysis of data from three contributing centres within the intraoperative electron-beam radiation therapy (IOERT) Spanish program was performed to investigate the main contributions of IORT to the multidisciplinary treatment of high-risk extremity soft tissue sarcoma (STS). METHODS AND MATERIALS: Patients with an histologic diagnosis of primary extremity STS, with absence of distant metastases, undergoing limb-sparing surgery with radical intent, external beam radiotherapy (median dose 45 Gy) and IOERT (median dose 12.5 Gy) were considered eligible for participation in this study. RESULTS: From 1986-2012, a total of 159 patients were analysed in the study from three Spanish institutions. With a median follow-up time of 53 months (range 4-316 years), 5-year local control (LC) was 82 %. The 5-year IOERT in-field control, disease-free survival (DFS) and overall survival (OS) were 86, 62 and 72 %, respectively. On multivariate analysis, only microscopically involved margin (R1) resection status retained significance in relation to LC (HR 5.20, p < 0.001). With regard to IOERT in-field control, incomplete resection (HR 4.88, p = 0.001) and higher IOERT dose (≥ 12.5 Gy; HR 0.32, p = 0.02) retained a significant association in multivariate analysis. CONCLUSION: From this joint analysis emerges the fact that an IOERT dose ≥ 12.5 Gy increases the rate of IOERT in-field control, but DFS remains modest, given the high risk of distant metastases. Intensified local treatment needs to be tested in the context of more efficient concurrent, neo- and adjuvant systemic therapy.


Asunto(s)
Fraccionamiento de la Dosis de Radiación , Procedimientos Quirúrgicos Mínimamente Invasivos/mortalidad , Tratamientos Conservadores del Órgano/mortalidad , Radioterapia Conformacional/mortalidad , Radioterapia de Alta Energía/mortalidad , Sarcoma/mortalidad , Sarcoma/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada/métodos , Terapia Combinada/estadística & datos numéricos , Electrones/uso terapéutico , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , España/epidemiología , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
4.
Radiother Oncol ; 197: 110343, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38806114

RESUMEN

BACKGROUND AND PURPOSE: The optimal utilization rate of radiotherapy (oRUR) serves as a benchmark for assessing service demand and improving access to cancer care. While it is estimated that approximately 50 % of adult cancer patients require external beam radiotherapy during their treatment, there is a scarcity of data regarding the optimal use of radiotherapy in pediatric cancer. In this study, we adopted an established method and developed a model to estimate the oRUR in childhood neuroblastoma. MATERIALS AND METHODS: We developed a decision tree model to calculate the oRUR using indications for radiotherapy and corresponding epidemiological data collected through systematic review and meta-analysis. Sensitivity analyses were performed to evaluate the impact of variations in radiotherapy indications between treatment protocols and variables in the model. We calculated and compared the oRUR for global, high-income, and low- and middle-income settings. RESULTS: The oRUR for pediatric neuroblastoma was 64 % (95 % CI: 58 %-71 %) in the global setting, 50 % in high-income countries, and 68 % in low- and middle-income countries. The impact of variation in radiotherapy indications between major international treatment protocols was negligible. CONCLUSION: The knowledge of oRUR is crucial for evaluating current practices, identifying gaps in access, and planning future radiotherapy services for treating childhood cancer. Based on our results, 64 % of children with neuroblastoma have an indication for radiotherapy. Patients in low- and middle-income countries have more indications for radiotherapy than those in high-income countries, due to a more adverse tumour stage distribution caused by limited access to healthcare resources.

5.
Int J Radiat Oncol Biol Phys ; 118(3): 595-604, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37979709

RESUMEN

PURPOSE: To meet the demand for cervical cancer care in Africa, access to surgical and radiation therapy services needs to be understood. We thus mapped the availability of gynecologic and radiation therapy equipment and staffing for treating cervical cancer. METHODS AND MATERIALS: We collected data on gynecologic and radiation oncology staffing, equipment, and infrastructure capacities across Africa. Data was obtained from February to July 2021 through collaboration with international partners using Research Electronic Data Capture. Cancer incidence was taken from the International Agency for Research on Cancer's GLOBOCAN 2020 database. Treatment capacity, including the numbers of radiation oncologists, radiation therapists, physicists, gynecologic oncologists, and hospitals performing gynecologic surgeries, was calculated per 1000 cervical cancer cases. Adequate capacity was defined as 2 radiation oncologists and 2 gynecologic oncologists per 1000 cervical cancer cases. RESULTS: Forty-three of 54 African countries (79.6%) responded, and data were not reported for 11 countries (20.4%). Respondents from 31 countries (57.4%) reported access to specialist gynecologic oncology services, but staffing was adequate in only 11 countries (20.4%). Six countries (11%) reported that generalist obstetrician-gynecologists perform radical hysterectomies. Radiation oncologist access was available in 39 countries (72.2%), but staffing was adequate in only 16 countries (29.6%). Six countries (11%) had adequate staffing for both gynecologic and radiation oncology; 7 countries (13%) had no radiation or gynecologic oncologists. Access to external beam radiation therapy was available in 31 countries (57.4%), and access to brachytherapy was available in 25 countries (46.3%). The number of countries with training programs in gynecologic oncology, radiation oncology, medical physics, and radiation therapy were 14 (26%), 16 (30%), 11 (20%), and 17 (31%), respectively. CONCLUSIONS: We identified areas needing comprehensive cervical cancer care infrastructure, human resources, and training programs. There are major gaps in access to radiation oncologists and trained gynecologic oncologists in Africa.


Asunto(s)
Neoplasias de los Genitales Femeninos , Oncología por Radiación , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/radioterapia , Recursos Humanos , África/epidemiología
6.
Lancet Reg Health Southeast Asia ; 16: 100218, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37694176

RESUMEN

Background: High-dose-rate image guided brachytherapy (IGBT) for cervical cancer leads to improved local control and reduced toxicity and is a critical component of treatment. However, transition to IGBT requires capacity upscaling. An institutional activity mapping and national impact analysis of such a transition were undertaken to understand feasibility. Methods: Between September 2020 and March 2021, activity mapping was conducted in a high-volume centre that triaged cervical cancer patients for brachytherapy into four workflows; A: two-dimensional (2D) X-Ray point A-based intracavitary brachytherapy, B: CT point A-based intracavitary brachytherapy, C: MRI/CT-volume based intracavitary brachytherapy, D: MRI/CT volume-based intracavitary +/- interstitial brachytherapy. Clinical process time mapping was performed, and case scenarios for transition were modelled at the institutional and national levels based on available incidence and infrastructure levels. Treatment capacity changes were calculated, and potential strategies for workflow reorganisation were proposed. Findings: Eighty-four patients were included in the study. The total time taken for the workflows A, B, C, and D were 176 min (57-208), 224 min (74-260), 267 min (101-302), and 348 min (232-383), respectively. The transition from workflow A to D through sequential steps led to 35%, 49%, and 64% loss of treatment capacity in the index institution. Solutions such as 10-hour or 12-hour overlapping shifts increased treatment capacity by 25% and 50% and performing single implants and delivering multiple fractions increased capacity by 100%. Twenty-three Indian states and Union Territories are predicted to be able to transition to advanced workflows. For four Indian states, it may be detrimental considering the current infrastructure level, and eight Indian states lacked brachytherapy access. Further financial investment is required in the latter 12 states for transition to advanced workflows. Interpretation: Our study demonstrates that unplanned transition to IGBT can lead to treatment capacity loss and increase in waiting lists to access treatment. The proposed solutions of workflow reorganisation, using strategies such as single brachytherapy applicator implant and delivering multiple treatment fractions can improve access to treatment for women with cervix cancer in resource-strained and high patient-volume settings. We recommend state-wise solutions for the upscale from conventional 2D workflows to IGBT, subject to the availability of skilled personnel, infrastructure and training. Financial investments may be needed in some states to achieve this goal. Funding: International Atomic Energy Agency (IAEA) supported the salary of VH through project E33042 that focussed on implementation strategies of image guided brachytherapy.

7.
Int J Radiat Oncol Biol Phys ; 116(2): 448-458, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36549348

RESUMEN

PURPOSE: Latin America faces a shortage in radiation therapy (RT) units and qualified personnel for timely and high-quality treatment of patients with cancer. Investing in equitable and inclusive access to RT over the next decade would prevent thousands of deaths. Measuring the investment gap and payoff is necessary for stakeholder discussions and capacity planning efforts. METHODS AND MATERIALS: Data were collected from the International Atomic Energy Agency's Directory of Radiotherapy Centers, industry stakeholders, and individual surveys sent to national scientific societies. Nationwide data on available devices and personnel were compiled. The 10 most common cancers in 2020 with RT indication and their respective incidence rates were considered for gap calculations. The gross 2-year financial return on investment was calculated based on an average monthly salary across Latin America. A 10-year cost projection was calculated according to the estimated population dynamics for the period until 2030. RESULTS: Eleven countries were included in the study, accounting for 557,213,447 people in 2020 and 561 RT facilities. Approximately 1,065,684 new cancer cases were diagnosed, and a mean density of 768,469 (standard deviation ±392,778) people per available unit was found. By projecting the currently available treatment fractions to determine those required in 2030, it was found that 62.3% and 130.8% increases in external beam RT and brachytherapy units are needed from the baseline, respectively. An overall regional investment of approximately United States (US) $349,650,480 in 2020 would have covered the existing demand. An investment of US $872,889,949 will be necessary by 2030, with the expectation of a 2-year posttreatment gross return on investment of more than US $2.1 billion from patients treated in 2030 only. CONCLUSIONS: Investment in RT services is lagging in Latin America in terms of the population's needs. An accelerated outlay could save additional lives during the next decade, create a self-sustaining system, and reduce region-wide inequities in cancer care access. Cash flow analyses are warranted to tailor precise national-level intervention strategies.


Asunto(s)
Braquiterapia , Neoplasias , Oncología por Radiación , Humanos , América Latina/epidemiología , Neoplasias/radioterapia , Inversiones en Salud
8.
Rep Pract Oncol Radiother ; 17(4): 233-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-24377029

RESUMEN

The gastric antral vascular ectasia (GAVE) is a well recognizable endoscopic entity characterized by the presence of multiple linear angioectatic vessels predominantly located in the antrum, with a typical appearance of "watermelon stomach". This condition typically affects elderly females presenting as iron-deficiency anaemia due to chronic gastric bleeding. Standard treatment is endoscopic ablation of the gastric mucosa. For non-responders, radical surgery is considered a curative treatment but with considerable morbidity and mortality. Radiation therapy is a well-known alternative for many benign diseases, including anomalous vascular hyperproliferative diseases, although its role has not been defined for GAVE. The present case illustrates the efficacy and tolerance of radiotherapy in the treatment of symptomatic gastric watermelon.

9.
Rep Pract Oncol Radiother ; 17(3): 163-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-24377019

RESUMEN

BACKGROUND: Extramammary Paget disease (EMPD) is a rare condition that most commonly affects the anogenital region in the elderly. It may be associated with an underlying invasive carcinoma. Surgical excision is nowadays considered a standard treatment for extramammary Paget's disease, although this approach might not be suitable for all patients. Good rates of local control and cosmetic outcome have been achieved by using high-dose-rate (HDR) plesiotherapy in the treatment of skin tumors arising in different locations. MATERIAL AND METHODS: We present the results observed in a patient with EMPD treated by HDR plesiotherapy with a custom-made mold up to a final dose of 54 Gy in 12 fractions of 450 cGy over 4 weeks. RESULTS: After a follow-up of 18 months, the patient is alive and without evidence of local or distant relapse. Acute toxicity was acceptable and cosmetic result was considered as excellent. CONCLUSION: This technique represents an attractive alternative for those patients who are not candidates for surgical procedures because of unacceptable risk of disfigurements or functional impairment, medical contraindications or patient preference.

10.
JCO Glob Oncol ; 8: e2200106, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36122318

RESUMEN

PURPOSE: Vulnerable populations face geographical barriers in accessing radiotherapy (RT) facilities, resulting in heterogeneity of care received and cancer burden faced. We aimed to explore the current use of Geographical Information Systems (GIS) in access to RT and use these findings to create sustainable solutions against barriers for access in low- and middle-income countries. MATERIALS AND METHODS: A systematic review using the PRISMA search strategy was done for studies using GIS to explore outcomes among patients with cancer. Included studies were reviewed and classified into three umbrella categories of how GIS has been used in studying access to RT. RESULTS: Forty articles were included in the final review. Thirty-eight articles were set in high-income countries and two in upper-middle-income countries. Included studies were published from 2000 to 2020, and were comprised of patients with all-cancers combined, breast, colon, skin, lung, prostate, ovarian, and rectal carcinoma patients. Studies were categorized under three groups on the basis of how they used GIS in their analyses: to describe geographic access to RT, to associate geographic access to RT with outcomes, and for RT planning. Most studies fell under multiple categories. CONCLUSION: Although this field is relative nascent, there is a wide array of functions possible through GIS for RT planning, including identifying high-risk populations, improving access in high-need areas, and providing valuable information for future resource allocation. GIS should be incorporated in future studies, especially set in low- and middle-income countries, which evaluate access to RT.


Asunto(s)
Neoplasias , Oncología por Radiación , Sistemas de Información Geográfica , Geografía , Humanos , Renta , Neoplasias/radioterapia
11.
JAMA Netw Open ; 5(8): e2226319, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35951324

RESUMEN

Importance: Radiotherapy is critical for comprehensive cancer care, but there are large gaps in access. Within Ghana, data on radiotherapy availability and on the relationship between distance and access are unknown. Objectives: To estimate the gaps in radiotherapy machine availability in Ghana and to describe the association between distance and access to care. Design, Setting, and Participants: This is a cross-sectional, population-based study of radiotherapy delivery in Ghana in 2020 and model-based analysis of radiotherapy demand and the radiotherapy utilization rate (RUR) using the Global Task Force on Radiotherapy for Cancer Control investment framework. Exposures: Receipt of radiotherapy and the number of radiotherapy courses delivered. Main Outcomes and Measures: Geocoded location of patients receiving external beam radiotherapy (EBRT); median Euclidean distance from the district centroids to the nearest radiotherapy centers; proportion of population living within geographic buffer zones of 100, 150, and 200 km; additional capacity required for optimal utilization; and geographic accessibility after strategic location of a radiotherapy facility in an underserviced region. Results: A total of 2883 patients underwent EBRT courses in 2020, with an actual RUR of 11%. Based on an optimal RUR of 48%, 11 524 patients had an indication for radiotherapy, indicating that only 23% of patients received treatment. An investment of 23 additional EBRT machines would be required to meet demand. The median Euclidean distance from the district centroids to the nearest radiotherapy facility was 110.6 km (range, 0.62-513.2 km). The proportion of the total population living within a radius of 100, 150 and 200 km of a radiotherapy facility was 47%, 61% and 70%, respectively. A new radiotherapy facility in the northern regional capital would reduce the median of Euclidean distance by 10% to 99.4 km (range, 0.62-267.7 km) and increase proportion of the total population living within a radius of 100, 150 and 200 km to 53%, 69% and 84%, respectively. The greatest benefit was seen in regions in the northern half of Ghana. Conclusions and Relevance: In this cross-sectional study of geographic accessibility and availability of radiotherapy, Ghana had major national deficits of radiotherapy capacity, with significant geographic disparities among regions. Well-planned infrastructure scale-up that accounts for the population distribution could improve radiotherapy accessibility.


Asunto(s)
Accesibilidad a los Servicios de Salud , Estudios Transversales , Ghana/epidemiología , Humanos
12.
Radiother Oncol ; 176: 83-91, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36113775

RESUMEN

BACKGROUND: In 2015, the Global Task Force on Radiotherapy for Cancer Control (GTFRCC) called for 80% of National Cancer Control Plans (NCCP) to include radiotherapy by 2020. As part of the ongoing ESTRO Global Impact of Radiotherapy in Oncology (GIRO) project, we assessed whether inclusion of radiotherapy in NCCPs correlates with radiotherapy machine availability, national income, and geographic region. METHODS: A previously validated checklist was used to determine whether radiotherapy was included in each country's NCCP. We applied the CCORE optimal radiotherapy utilisation model to the GLOBOCAN 2020 data to estimate the demand for radiotherapy and compared this to the International Atomic Energy Agency (IAEA) Directory of Radiotherapy Centres (DIRAC) supply data, stratifying by income level and world region. World regions were defined according to the IAEA. FINDINGS: Complete data (including GLOBOCAN 2020, DIRAC and NCCP) was available for 143 countries. Over half (55%, n = 79) included a radiotherapy-specific checklist item within the plan. Countries which included radiotherapy services planning in their NCCP had a higher median number of machines (1.68 vs 0.75 machines/1000 patients needing radiotherapy, p < 0.001). There was significant regional and income-level heterogeneity in the inclusion of radiotherapy-related items in NCCPs. Low-income and Asia-Pacific countries were least likely to include radiation oncology services planning in their NCCP (p = 0.06 and p = 0.003, respectively). Few countries in the Asia-Pacific (18.6%) had a plan to develop or maintain radiation services, compared to 57% of countries in Europe. INTERPRETATION: Only 55% of current NCCPs included any information regarding radiotherapy, below the GTFRCC's target of 80%. Prioritisation of radiotherapy in NCCPs was correlated with radiotherapy machine availability. There was regional and income-level heterogeneity regarding the inclusion of specific radiotherapy checklist items in the NCCPs. Ongoing efforts are needed to promote the inclusion of radiotherapy in future iterations of NCCPs in order to improve global access to radiation treatment. FUNDING: No direct funding was used in this research.


Asunto(s)
Neoplasias , Oncología por Radiación , Humanos , Neoplasias/radioterapia , Atención a la Salud , Agencias Internacionales , Geografía , Radioterapia
13.
Radiother Oncol ; 146: 1-8, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32065874

RESUMEN

BACKGROUND: A high cancer burden exists among indigenous populations worldwide. Canada and Greenland have similar geographic features that make health service delivery challenging. We sought to describe geographic access to radiotherapy for indigenous populations in both regions. METHODS: We used geospatial analyses to calculate distance and travel-time from indigenous communities in Canada and Greenland to the nearest radiotherapy center. We calculated the proportion of indigenous communities and populations residing within a 1 and 2-hour drive of a radiotherapy center in Canada, and compared the proportion of indigenous versus non-indigenous populations residing within each drive-time area. We calculated the potential distance and travel-time saved if radiotherapy was available in northern Canada (Yellowknife and Iqaluit), and Greenland (Nuuk). RESULTS: Median one-way travel from indigenous communities to nearest radiotherapy center in Canada was 268 km (3 h when considering any transportation mode), and 4111 km (6 h by plane) in Greenland. In Canada, 84% and 68% of indigenous communities were outside a 1 and 2-hour drive from a radiotherapy center, respectively. Only 2% of the total population in Canada resided outside a 2-hour drive from a radiotherapy center. However, indigenous peoples were 336 times more likely to live more than a 2-hour drive away, compared to non-indigenous peoples. Nearly 3 million km and 4000 h of travel could be saved over a 10-year period for patients with newly diagnosed cancers in Canada, and 7 million km and 10,000 h in Greenland, if radiotherapy was available in Yellowknife, Iqaluit and Nuuk. CONCLUSIONS: Geography is an important barrier to accessing radiotherapy for indigenous populations in Canada and Greenland. A significant disparity exists between indigenous and non-indigenous peoples in Canada. Geospatial analyses can help highlight disparities in access to inform radiotherapy service planning.


Asunto(s)
Neoplasias , Canadá , Groenlandia , Humanos , Neoplasias/radioterapia , Viaje
14.
Brachytherapy ; 8(3): 290-6, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19428308

RESUMEN

PURPOSE: To analyze the results of episcleral plaque brachytherapy from the Catalan Institute of Oncology in Spain. MATERIALS AND METHODS: From September 1996 through December 2004, 120 patients with choroidal melanoma (median age, 59 years) were treated with iodine-125 seeds at our institution. Patients were classified according to the criteria developed by the Collaborative Ocular Melanoma Study (COMS) group, as follows-COMS-I: 3 patients; COMS-II: 87 patients; COMS-III: 24 patients; and indeterminate COMS: 9 patients. Followup ranged from 1 year to 8.4 years. RESULTS: Overall survival at 5 and 8 years was 83.9% and 73.3%, respectively. The 5- and 8-year specific survival rate was 85.7%. Local control was 88.2% and 72.7% at 5 and 8 years, respectively. The most common treatment-related toxicity was cataract formation (31.6% of cases), followed by radiation retinopathy (7.5%) and retinal detachment (4.1%). CONCLUSION: The results of this institutional retrospective study confirm that the use of iodine-125 episcleral plaques to treat choroidal melanoma offers the potential for conserving a functioning eyeball. The toxicity profile is favorable and disease control is similar to other techniques.


Asunto(s)
Braquiterapia/métodos , Neoplasias de la Coroides/radioterapia , Melanoma/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Braquiterapia/efectos adversos , Neoplasias de la Coroides/mortalidad , Supervivencia sin Enfermedad , Femenino , Humanos , Radioisótopos de Yodo , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Dosificación Radioterapéutica , Estudios Retrospectivos , España
15.
Radiother Oncol ; 141: 48-55, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31575428

RESUMEN

BACKGROUND AND PURPOSE: Canada is a high-income country with universal healthcare. In international comparisons, its overall level of access to radiotherapy appears sufficient. However, challenges exist due to Canada's large geographic area and small population density. The association between access and cancer outcomes nationally has not yet been described. MATERIALS AND METHODS: We quantified geographic accessibility for 2012 using the linear distance from each Canadian health region centroid to the nearest radiotherapy center. We used geospatial analytic techniques to detect clusters of age-standardized all-cancer mortality-to-incidence ratios (MIRs) across health regions, from 2010-2012. Global ordinary least squares (OLS) and geographically-weighted regression (GWR) were conducted to examine relationships between distance and MIR, adjusting for sociodemographic factors. RESULTS: Median distance from health region centroid to nearest radiotherapy center was 101.73 km (range 1.14-2095.12). One cluster of worse outcomes (MIR range 0.45-0.88) involved most of northern Canada, with a second cluster of better outcomes (MIR range 0.40-0.41) in southern British Columbia. In both regression models, regions with longer distance to radiotherapy center (ß = 0.0001), increased smoking (ß = 0.002), and poorer food security (ß = -0.003) were significantly associated with worse outcomes (OLS R2 = 0.70, GWR R2 = 0.74). Distance remained independently associated with MIR for lung and colorectal cancer subgroups, but not breast and prostate. CONCLUSIONS: A clear north-south discordance in cancer outcomes exists in Canada, with poorer outcomes in the north, while radiotherapy centers are concentrated along the south. Increased distance to radiotherapy, along with other sociodemographic and health-system factors, are associated with poorer cancer outcomes. Our study could be replicated, particularly in other high-income countries, to help identify national patterns and regional disparities in access and outcomes.


Asunto(s)
Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Disparidades en Atención de Salud/estadística & datos numéricos , Neoplasias/radioterapia , Colombia Británica/epidemiología , Canadá/epidemiología , Análisis por Conglomerados , Femenino , Sistemas de Información Geográfica , Humanos , Incidencia , Renta , Masculino , Persona de Mediana Edad , Neoplasias/epidemiología , Pronóstico , Fumar/epidemiología , Resultado del Tratamiento
16.
Bioresour Technol ; 99(7): 2141-7, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17624772

RESUMEN

The effects of amendment with municipal solid waste compost (MSWC) and sewage sludge (SS) on acid-base properties of soil humic acids (HAs) were investigated. For this purpose, HAs were isolated from MSWC and SS and two different Portuguese soils, one sandy and the other clay loam, either unamended or amended with MSWC or SS at a rate of 60 t ha(-1), and analysed by potentiometric titrations at various ionic strengths (0.01, 0.05, 0.1 and 0.3M) over the pH range from 3.5 to 10.5. All titration data were fitted with the NICA-Donnan model and the variations of model parameters between the various HA samples were discussed. The HAs from MSWC and SS had lower acidic functional group contents and higher proton binding affinities than the control soil HAs. Amending soils with MSWC and SS determined a decrease of acidic functional group contents and an increase on proton binding affinities of soil HAs. These effects were more evident in SS-amended soil HAs than in MSWC-amended soil HAs, and in clay loam soil HA than in sandy soil HA.


Asunto(s)
Sustancias Húmicas/análisis , Aguas del Alcantarillado , Suelo , Silicatos de Aluminio , Arcilla , Concentración de Iones de Hidrógeno , Protones , Dióxido de Silicio , Termodinámica
17.
Waste Manag ; 28(11): 2183-91, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18042373

RESUMEN

The effects of amendment with municipal solid waste compost (MSWC) and anaerobically digested sewage sludge (SS) on the compositional and structural features of soil humic acids (HAs) were investigated. For this purpose, HAs were isolated from MSWC, SS, and two different Portuguese soils, a sandy Haplic Podzol and a clay loam Calcic Vertisol, which were either unamended or amended with MSWC or SS at a rate of 60 t ha(-1). The isolated HAs were analyzed for elemental and acidic functional group composition, and by ultraviolet/visible, Fourier transform infrared (FT IR), and fluorescence spectroscopies. The application of MSWC and especially SS to soils determined an increase of C, N, H, and S contents and E4/E6 ratios (i.e., ratios of absorbances at 465 and 665 nm), and a decrease of O, COOH, and phenolic OH contents and C/N, C/H, and O/C ratios of soil HAs. The FT IR and fluorescence results showed that the organic amendments, especially SS, caused an increase of the aliphatic character and a decrease of the degrees of aromatic polycondensation, polymerization, and humification of amended soil HAs. Both MSWC and SS affected more markedly the clayey soil HAs than the sandy soil HAs, possibly due to less extended mineralization processes and the protective action of clay minerals on amended soil HAs.


Asunto(s)
Sustancias Húmicas/análisis , Eliminación de Residuos/métodos , Aguas del Alcantarillado , Suelo/análisis , Elementos Químicos , Compuestos Orgánicos/análisis , Portugal , Espectroscopía Infrarroja por Transformada de Fourier , Agua/análisis
18.
Radiother Oncol ; 83(1): 3-10, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17321620

RESUMEN

The aim of this paper is to supplement the GEC/ESTRO/EAU recommendations for permanent seed implantations in prostate cancer to develop consistency in target and volume definition for permanent seed prostate brachytherapy. Recommendations on target and organ at risk (OAR) definitions and dosimetry parameters to be reported on post implant planning are given.


Asunto(s)
Braquiterapia , Neoplasias de la Próstata/radioterapia , Humanos , Masculino , Neoplasias de la Próstata/patología , Traumatismos por Radiación/etiología , Dosificación Radioterapéutica , Recto/efectos de la radiación , Uretra/efectos de la radiación
19.
J Agric Food Chem ; 55(20): 8206-12, 2007 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-17877411

RESUMEN

Sewage sludge obtained by a conventional aerobic activated sludge process (CSS), P-rich sewage sludge from an enhanced biological P removal process (PRS), and struvite (MgNH 4PO 4 x 6H 2O) recovered from an anaerobic digester supernatant using a low-grade MgO byproduct from the calcination of natural magnesite as a Mg source (STR) were evaluated as P sources for plant growth. For this purpose, a greenhouse pot experiment was conducted using a P-deficient loamy sand soil and perennial ryegrass ( Lolium perenne L.) as the test crop. The P sources were applied at rates equivalent to 0, 9, 17, 26, 34, and 44 mg/kg P. Single superphosphate (SUP) was used as reference for comparison with the other P sources. The results obtained indicated that STR was as effective as SUP in increasing the dry matter yield and supplying P to ryegrass. Compared to SUP and STR, PRS and especially CSS exhibited less agronomic effectiveness as P sources, which may be attributed, at least partially, to greater soil P fixation because of the larger amount of Fe incorporated with these materials.


Asunto(s)
Agricultura/métodos , Lolium/crecimiento & desarrollo , Compuestos de Magnesio/administración & dosificación , Fosfatos/administración & dosificación , Fósforo/administración & dosificación , Aguas del Alcantarillado/química , Fertilizantes , Lolium/metabolismo , Estruvita
20.
Bioresour Technol ; 98(1): 29-37, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16427275

RESUMEN

The potential impact of different types of organic (sewage sludge) or inorganic (mineral fertilizer) amendments to a basic soil was investigated under dry conditions. A soil incubation experiment was carried out over 64 days; there were two fertility treatments: sewage sludge (SS) (140 t ha(-1)), mineral fertilizer (M) and an unamended control (C). Two levels of irrigation were imposed: (1) well-watered, kept at 60% of its water holding capacity, and (2) water-deficit at 6%. Available N-NO3-, N-NH4+ and P, and electrical conductivity (EC) increased in SS and M-treated soils. Under well-watered conditions activities of some enzymes (protease-BAA, phosphatase and beta-glucosidase), and microbiological properties (microbial biomass carbon, basal respiration and dehydrogenase activity) were stimulated in SS-treated soils. Under water-deficit conditions, protease-BAA, phosphatase and beta-glucosidase activities, and basal respiration were more reduced in SS than in C and M. Results showed that under severe dry conditions, soil microbial activity always remained higher in organic amended soils than when mineral fertilizer was added.


Asunto(s)
Fertilizantes/análisis , Aguas del Alcantarillado/análisis , Microbiología del Suelo , Agua/análisis , Amoníaco/análisis , Proteínas Bacterianas/análisis , Biomasa , Nitratos/análisis , Fósforo/química , Factores de Tiempo
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