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1.
BMC Health Serv Res ; 24(1): 417, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38570764

ABSTRACT

BACKGROUND: Adjuvant radiotherapy represents a key component in curative-intent treatment for early-stage breast cancer patients. In recent years, two accelerated partial breast irradiation (APBI) techniques are preferred for this population in our organization: electron-based Intraoperative radiation therapy (IORT) and Linac-based External Beam Radiotherapy, particularly Intensity-modulated radiation therapy (IMRT). Recently published long-term follow-up data evaluating these technologies have motivated a health technology reassessment of IORT compared to IMRT. METHODS: We developed a Markov model to simulate health-state transitions from a cohort of women with early-stage breast cancer, after lumpectomy and adjuvant APBI using either IORT or IMRT techniques. The cost-effectiveness from a private health provider perspective was assessed from a disinvestment point of view, using life-years (LYs) and recurrence-free life-years (RFLYs) as measure of benefits, along with their respective quality adjustments. Expected costs and benefits, and the incremental cost-effectiveness ratio (ICER) were reported. Finally, a sensitivity and scenario analyses were performed to evaluate the cost-effectiveness using lower IORT local recurrence and metastasis rates in IORT patients, and if equipment maintenance costs are removed. RESULTS: IORT technology was dominated by IMRT in all cases (i.e., fewer benefits with greater costs). Despite small differences were found regarding benefits, especially for LYs, costs were considerably higher for IORT. For sensitivity analyses with lower recurrence and metastasis rates for IORT, and scenario analyses without equipment maintenance costs, IORT was still dominated by IMRT. CONCLUSIONS: For this cohort of patients, IMRT was, at least, non-inferior to IORT in terms of expected benefits, with considerably lower costs. As a result, IORT disinvestment should be considered, favoring the use of IMRT in these patients.


Subject(s)
Breast Neoplasms , Radiotherapy, Intensity-Modulated , Humans , Female , Breast Neoplasms/radiotherapy , Breast Neoplasms/surgery , Breast Neoplasms/pathology , Cost-Benefit Analysis , Intraoperative Care/methods , Radiotherapy, Adjuvant , Mastectomy, Segmental/methods
2.
Medwave ; 23(4)2023 May 25.
Article in English | MEDLINE | ID: mdl-37233030

ABSTRACT

Introduction: Prostate cancer is one of the most frequent cancers in Chile, with 8157 new cases in 2020. Worldwide, 5 to 10% of men have metastatic disease at diagnosis, and androgen deprivation therapy with or without chemotherapy is the standard of care for these patients. The use of local treatment in this setting has no formal recommendation due to the lack of high-quality evidence. Some retrospective studies have sought to elucidate the benefit of surgery on the primary tumor in the setting of metastatic disease since it has been proven to be an effective local treatment for other metastatic malignant diseases. Despite these efforts, the benefit of cytoreductive radical prostatectomy as local treatment in these patients remains unclear. Methods: We searched Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, and Cochrane, among others. We extracted data from systematic reviews, reanalyzed data from primary studies, conducted a meta-analysis, and generated a summary results table using the GRADE approach. Results and conclusions: We identified 12 systematic reviews, including seven studies in total, none of which was a trial. Only six of those seven primary studies were used in the results summary. Despite the lack of high-quality evidence, the results summary shows the benefits of performing surgery on the primary tumor in terms of all-cause mortality, cancer-specific mortality, and disease progression. There was also a potential benefit in local complications related to the progression of the primary tumor, supporting the implementation of this intervention in patients with metastatic disease. The absence of formal recommendations highlights the need to evaluate the benefits of surgery on a case-by-case basis, presenting the available evidence to patients for a shared decision-making process and considering future local complications that could be difficult to manage.


Subject(s)
Prostatic Neoplasms , Male , Humans , Prostatic Neoplasms/surgery , Prostatic Neoplasms/pathology , Retrospective Studies , Cytoreduction Surgical Procedures , Androgen Antagonists/therapeutic use , Systematic Reviews as Topic , Prostatectomy/methods
3.
Medwave ; 23(4): e2661, 31-05-2023.
Article in English | LILACS-Express | LILACS | ID: biblio-1436201

ABSTRACT

Introducción El cáncer de próstata es uno de los cánceres más frecuentes en Chile, con 8157 nuevos casos en 2020. A nivel mundial, 5 a 10% de los hombres presentan metástasis al diagnóstico, y la terapia de deprivación androgénica con o sin quimioterapia es el estándar de cuidado para estos pacientes. El uso de tratamiento local en este contexto tiene una recomendación formal debido a la falta de evi-dencia de alta calidad. Algunos estudios retrospectivos han intentado dilucidar el beneficio de la cirugía sobre el tumor primario en el contexto de la enfermedad metastásica, ya que se ha demostrado que es un tratamiento local eficaz para otras neoplasias metastá-sicas. A pesar de estos esfuerzos, el beneficio de la prostatectomía radical citorreductora como tratamiento local en estos pacientes sigue sin estar claro. Métodos Se realizó una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, que se mantiene mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE y Cochrane, entre otras. Se extrajeron los datos de las revisiones sistemáticas, se volvieron a analizar los datos de los estudios primarios, se realizó un metanálisis y se generó una tabla de resumen de resultados utilizando el enfoque GRADE. Resultados y conclusiones Se identificaron 12 revisiones sistemáticas, que incluían siete estudios primarios en total, ninguno de los cuales era un ensayo alea-torizado controlado. Sólo seis de esos siete estudios primarios se utilizaron en el resumen de resultados. A pesar de la falta de evi-dencia de alta calidad, los resultados de este resumen muestran los beneficios de realizar la cirugía en el tumor primario en términos de mortalidad por cualquier causas, mortalidad específica por cáncer y progresión de la enfermedad. También se observó un bene-ficio potencial en las complicaciones locales relacionadas con la progresión del tumor primario, lo que apoya la realización de esta intervención en pacientes con enfermedad metastásica. La ausencia de recomendaciones formales subraya la necesidad de evaluar los beneficios de la cirugía caso por caso, presentando la evidencia disponibles a los pacientes para un proceso de toma de decisiones compartido, teniendo en cuenta las futuras complicaciones locales que podrían ser difíciles de manejar.


Introduction Prostate cancer is one of the most frequent cancers in Chile, with 8157 new cases in 2020. Worldwide, 5 to 10% of men have metastatic disease at diagnosis, and androgen deprivation therapy with or without chemotherapy is the standard of care for these patients. The use of local treatment in this setting has no formal recommendation due to the lack of high- quality evidence. Some retrospective studies have sought to elucidate the benefit of surgery on the primary tumor in the setting of metastatic disease since it has been proven to be an effective local treatment for other metastatic malignant diseases. Despite these efforts, the benefit of cytoreductive radical prostatectomy as local treatment in these patients remains unclear. Methods We searched Epistemonikos, the largest database of systematic reviews in health, which is main-tained by screening multiple information sources, including MEDLINE, EMBASE, and Cochrane, among others. We extracted data from systematic reviews, reanalyzed data from primary studies, conducted a meta- analysis, and generated a summary results table using the GRADE approach. Results and conclusions We identified 12 systematic reviews, including seven studies in total, none of which was a trial. Only six of those seven primary studies were used in the results summary. Despite the lack of high- quality evidence, the results summary shows the benefits of performing surgery on the primary tumor in terms of all- cause mortality, cancer- specific mortality, and disease progression. There was also a potential benefit in local complications related to the progression of the prima-ry tumor, supporting the implementation of this intervention in patients with metastatic disease. The absence of formal recommendations highlights the need to evaluate the benefits of surgery on a case- by- case basis, presenting the available evidence to patients for a shared decision- making process and considering future local complications that could be difficult to manage.

4.
Biol Lett ; 14(6)2018 06.
Article in English | MEDLINE | ID: mdl-29899130

ABSTRACT

G. L. Stebbins' most effective pollinator principle states that when pollinators are not limiting, plants are expected to specialize and adapt to the most abundant and effective pollinator species available. In this study, we quantify the effectiveness of bees, hummingbirds and hawkmoths in a Chilean population of Erythranthe lutea (Phrymaceae), and examine whether flower traits are subject to pollinator-mediated selection by the most effective pollinator species during two consecutive years. Unlike most species in the pollinator community, the visitation rate of the recently arrived Bombus terrestris did not change substantially between years, which together with its high and stable pollen delivery to flower stigmas made this species the most important in the pollinator assemblage, followed by the solitary bee Centris nigerrima Flower traits were under significant selection in the direction expected for short-tongue bees, suggesting that E. lutea is in the initial steps of adaptation to the highly effective exotic bumblebee. Our results illustrate the applicability of Stebbins' principle for new invasive pollinators, and stress their importance in driving flower adaptation of native plant species, a critical issue in the face of biotic exchange and homogenization.


Subject(s)
Flowers/anatomy & histology , Magnoliopsida/anatomy & histology , Pollination , Animals , Appetitive Behavior , Bees , Birds , Chile , Introduced Species , Moths , Selection, Genetic
5.
PLoS One ; 11(1): e0146437, 2016.
Article in English | MEDLINE | ID: mdl-26785039

ABSTRACT

Herbivory has been long considered an important component of plant-animal interactions that influences the success of invasive species in novel habitats. One of the most important hypotheses linking herbivory and invasion processes is the enemy-release hypothesis, in which exotic plants are hypothesized to suffer less herbivory and fitness-costs in their novel ranges as they leave behind their enemies in the original range. Most evidence, however, comes from studies on leaf herbivory, and the importance of flower herbivory for the invasion process remains largely unknown. Here we present the results of a meta-analysis of the impact of flower herbivory on plant reproductive success, using as moderators the type of damage caused by floral herbivores and the residence status of the plant species. We found 51 papers that fulfilled our criteria. We also included 60 records from unpublished data of the laboratory, gathering a total of 143 case studies. The effects of florivory and nectar robbing were both negative on plant fitness. The methodology employed in studies of flower herbivory influenced substantially the outcome of flower damage. Experiments using natural herbivory imposed a higher fitness cost than simulated herbivory, such as clipping and petal removal, indicating that studies using artificial herbivory as surrogates of natural herbivory underestimate the real fitness impact of flower herbivory. Although the fitness cost of floral herbivory was high both in native and exotic plant species, floral herbivores had a three-fold stronger fitness impact on exotic than native plants, contravening a critical element of the enemy-release hypothesis. Our results suggest a critical but largely unrecognized role of floral herbivores in preventing the spread of introduced species into newly colonized areas.


Subject(s)
Ecosystem , Flowers/physiology , Genetic Fitness , Herbivory/physiology , Introduced Species , Plants/genetics , Animals , Genes, Plant , Plant Leaves/genetics , Plant Leaves/growth & development , Reproduction/physiology
6.
Glob Chang Biol ; 21(11): 3951-60, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26149368

ABSTRACT

Anthropogenic habitat disturbance is a strong biodiversity change driver that compromises not only the species persistence but also the ecological interactions in which they are involved. Even though seed dispersal is a key interaction involved in the recruitment of many tree species and in consequence critical for biodiversity maintenance, studies assessing the effect of different anthropogenic disturbance drivers on this interaction have not been performed under a meta-analytical framework. We assessed the way habitat fragmentation and degradation processes affect species diversity (abundance and species richness) and interaction rates (i.e., fruit removal and visitation rates) of different groups of seed-disperser species at a global scale. We obtained 163 case studies from 37 articles. Results indicate that habitat degradation had a negative effect on seed-disperser animal diversity, whereas habitat fragmentation had a negative effect on interaction rates. Birds and insects were more sensitive in terms of their diversity, whereas mammals showed a negative effect on interaction rates. Regarding habitat, both fragmentation and degradation had a negative effect on seed-disperser animal diversity only in temperate habitats, and negative effects on interaction rates in tropical and temperate habitats. Our results indicate that the impact of human disturbance on seed-disperser species and interactions is not homogeneous. On the contrary, the magnitude of effects seems to be dependent on the type of disturbance, taxonomic group under assessment, and geographical region where the human impact occurs.


Subject(s)
Birds/physiology , Feeding Behavior , Insecta/physiology , Mammals/physiology , Seed Dispersal , Animals , Climate , Conservation of Natural Resources , Ecosystem
7.
Naturwissenschaften ; 101(7): 599-602, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24880245

ABSTRACT

Habitat fragmentation and degradation are important biodiversity change drivers worldwide. Their effects have been described for many animal groups, but little is known about marsupials. We conducted a meta-analysis aiming to evaluate the actual effects of habitat fragmentation and degradation on forest marsupials. From a literature survey, we obtained 85 case studies reporting disturbance comparisons. We found a negative overall effect, as well as a negative effect for habitat fragmentation, but not for habitat degradation. Marsupials from Oceania were negatively affected by habitat disturbance, whereas there was no effect for those from South America. Arboreal marsupials were negatively affected, whereas terrestrial marsupials did not. Species from the families Dasyuridae (Antechinus spp.) and Microbiotheriidae (Dromiciops gliroides) showed to be sensitive to habitat disturbance.


Subject(s)
Ecosystem , Marsupialia/physiology , Trees , Animals , Australia , South America
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