Evaluation of ionizing radiation as a risk factor for the incidence of breast cancer: long-term analysis after the cesium-137 accident in Goiânia, Brazil. An ecological study

ABSTRACT BACKGROUND: The largest radiological accident to occur in any urban area happened in Goiânia, Brazil, in 1987. OBJECTIVE: To evaluate the association between breast cancer incidence and ionizing radiation levels. DESIGN AND SETTING: Ecological study among residents of the city of Goiânia, Brazil. METHODS: The central region of Goiânia, with seven major sources of contamination from cesium-137, was defined as the study area. The addresses of women diagnosed with breast cancer were identified between 2001 and 2010. The data were geographically referenced and, using census data, the annual averages of crude incidence rates were estimated. The existence of clusters of new cases was ascertained by means of the Moran index. Correlations of radiometric measurements with the incidence were assessed using unconditional linear regression. RESULTS: A total of 4,105 new cases were identified, of which 2,233 were in the study area, and of these, 1,286 (57.59%) were georeferenced. The gross rates of total and referenced cases were 102.91 and 71.86/100,000 women, respectively. These were close to the average for Brazilian state capitals, which is 79.37/100,000 women. The cluster analysis showed slight correlations in three small sets of census tracts, but these were far from the sources of contamination. The scatter plot of points and the R2 value close to zero indicated that there was no association between the variables. CONCLUSION: This study reinforces the hypothesis that the ionizing radiation levels to which women living in Goiânia are now exposed to are not associated with the onset of new cases of breast cancer.

Residential radon and lung cancer: a cohort study in Galicia, Spain / Radón residencial y cáncer de pulmón: un estudio de cohorte en Galicia, España / Radônio residencial e câncer de pulmão: um estudo de coorte na Galícia, Espanha

Case-control studies show an association between residential radon and lung cancer. The aim of this paper is to investigate this association through a cohort study. We designed an ambispective cohort study using the Galician radon map, Spain, with controls drawn from a previous case-control study. Subjects were recruited between 2002 and 2009. The data were cross-checked to ascertain lung cancer incidence and then analysed using a Cox regression model. A total of 2,127 subjects participated; 24 lung cancer cases were identified; 76.6% of subjects were drawn from the radon map. The adjusted hazard ratio was 1.2 (95%CI: 0.5-2.8) for the category of subjects exposed to 50Bq/m3 or more. This risk rose when subjects from the case-control study were analyzed separately. In conclusion, we did not observe any statistically significant association between residential radon exposure and lung cancer; however, it appears that with a sample of greater median age (such as participants from the case-control study), the risk of lung cancer would have been higher.

Los estudios de casos y controles muestran una asociación entre el radón residencial y el cáncer de pulmón. El objetivo del artículo fue investigar esa asociación a través de un estudio de cohorte. Proyectamos un estudio de cohorte ambispectivo, utilizando el mapa de radón de Galicia, España, con los controles obtenidos de un estudio anterior de casos y controles. Los individuos fueron reclutados entre 2002 y 2009. Los datos fueron verificados para confirmar la incidencia de cáncer de pulmón y después analizados con un modelo de regresión de Cox. Participaron un total de 2.127 individuos; se identificaron 24 casos de cáncer de pulmón; un 76,6% de los individuos fueron obtenidos a través del mapa de radón. El hazard ratio ajustado era 1,2 (IC95%: 0,5-2,8) para la categoría de individuos expuestos a 50Bq/m3 o más. El riesgo aumentó cuando los individuos del estudio de casos y controles fueron analizados separadamente. En conclusión, no se observó una asociación estadísticamente significativa entre exposición al radón residencial y cáncer de pulmón; sin embargo, parece que con una muestra con una media de edad más elevada (tales como los participantes del estudio de casos y controles), el riesgo de cáncer de pulmón habría sido más alto.

Estudos de casos e controles mostram uma associação entre radônio residencial e câncer de pulmão. O artigo teve como objetivo investigar essa associação através de um estudo de coorte. Projetamos um estudo ambispectivo coorte, utilizando o mapa de radônio da Galícia, Espanha, com os controles obtidos de um estudo anterior de casos e controles. Os indivíduos foram recrutados entre 2002 e 2009. Os dados foram verificados para confirmar a incidência de câncer de pulmão e depois analisados com um modelo de regressão de Cox. Participaram um total de 2.127 indivíduos; foram identificados 24 casos de câncer de pulmão; 76,6% dos indivíduos foram obtidos através do mapa de radônio. O hazard ratio ajustado era 1,2 (IC95%: 0,5-2,8) para a categoria de indivíduos expostos a 50Bq/m3 ou mais. O risco aumentou quando os indivíduos do estudo de casos e controles foram analisados separadamente. Em conclusão, não foi observada associação estatisticamente significativa entre exposição ao radônio residencial e câncer de pulmão; entretanto, parece que com uma amostra com mediana de idade mais elevada (tais como os participantes do estudo de casos e controles), o risco de câncer de pulmão teria sido mais alto.

Cutaneous melanoma in Latin America: the need for more data / El melanoma cutâneo en América Latina: la necesidad de mßs datos

OBJECTIVE: To identify the scientific literature on cutaneous melanoma in Latin America and compile all available epidemiologic data to demonstrate the need for reliable regional and country-specific data on incidence and mortality estimates. METHODS: Literature searches were conducted in PubMed, Embase, LILACS, and Google Scholar databases for epidemiologic studies from 1 January 2000 to 31 October 2010 related to melanoma in Argentina, Brazil, Colombia, Mexico, Puerto Rico, and Venezuela. A final search on melanoma cases was carried out using country-specific population-based cancer registries. No statistical analyses were conducted. RESULTS: For all six countries, most epidemiological research on cutaneous melanoma consists of hospital-based or case-control studies. Very few studies report incidence and mortality rates. Attempts to estimate disease rates have relied on national incidence and mortality data and information extracted from cancer registries. While predominance of European ancestry is a known risk factor for developing melanoma, the association of melanoma and ethnicity is not well-documented in some of the populations reviewed. Latin Americans are frequently exposed to ultraviolet (UV) radiation due to the tropical weather, high altitude, and thinning ozone layer in some regions. Tanned skin is viewed as healthy and beautiful. While melanoma public health campaigns have been under way in Latin America for decades, increasing melanoma awareness remains imperative. CONCLUSIONS: There is an urgent need to collect accurate epidemiologic melanoma data in Latin America. Future research in the region should include more comprehensive, countryspecific, population-based studies to allow for comparative evaluation of incidence and mortality rates.

OBJETIVO: Identificar la literatura científica sobre el melanoma cutßneo en América Latina y recopilar todos los datos epidemiológicos disponibles, con objeto de demostrar la necesidad de información fiable a escala regional y de país sobre los datos de incidencia y mortalidad. MÉTODOS: Se realizaron búsquedas bibliogrßficas en las bases de datos PubMed, Embase, LILACS y Google Scholar para encontrar estudios epidemiológicos relacionados con el melanoma llevados a cabo del 1 de enero del 2000 al 31 de octubre del 2010 en Argentina, Brasil, Colombia, México, Puerto Rico y Venezuela. Se efectuó una búsqueda final de casos de melanoma mediante la consulta de los registros poblacionales de cßncer de cada país. No se realizó ningún anßlisis estadístico. RESULTADOS: En los seis países, la mayor parte de la investigación epidemiológica sobre el melanoma cutßneo consiste en estudios hospitalarios o estudios de casos y testigos. Muy pocos estudios informan sobre las tasas de incidencia y mortalidad. Los intentos de calcular las tasas de la enfermedad se han basado en los datos nacionales de incidencia y mortalidad, y en la información extraída de los registros de cßncer. Aunque el predominio de la ascendencia europea constituye un conocido factor de riesgo de melanoma, la asociación entre el melanoma y el grupo étnico no puede demostrarse adecuadamente en algunas de las poblaciones estudiadas. Los latinoamericanos estßn frecuentemente expuestos a la radiación ultravioleta como consecuencia del clima tropical, la elevada altitud y la disminución de la capa de ozono en algunas regiones. La piel bronceada se considera como saludable y bella. Aunque hace decenios que se llevan a cabo campa±as de salud pública dedicadas al melanoma en América Latina, es indispensable incrementar la conciencia de esta enfermedad. Conclusiones: Existe la urgente necesidad de recopilar datos epidemiológicos precisos sobre el melanoma en América Latina. Las futuras actividades...

Primary cutaneous melanoma: an 18-year study

BACKGROUND: Primary cutaneous melanoma still constitutes the main cause of skin cancer death in developed countries, and its incidence in recent years has been increasing in a steady, worrisome manner. OBJECTIVES: This study evaluated the clinical, epidemiological and demographic aspects of this disease, and correlated them with patient prognosis. METHODS: Using epidemiologic and clinical data, we analyzed 84 patients with mild to severe primary cutaneous melanoma treated between 1990 and 2007. Slides containing surgical specimens were analyzed, and new slides were made from archived paraffin sections when necessary. RESULTS: The melanoma incidence was higher in areas of sun exposure, with lesions commonly observed in the trunk for males, and lower limbs for females. In addition to Breslow's thickness and ulceration (p = 0.043 and p < 0.001, respectively), the mitotic rate per mm² also correlated with worse patient outcome (p = 0.0007). The sum of ulceration (0 when absent or 1 when present), the Breslow index (1 when <1 mm, 2 when >1 mm and <4 mm, 3 when >4 mm) and the mitotic index (0 when absent or 1 when >1 per mm²) allowed the establishment of a prognostic score: if the sum was equal to or over three, nearly all (91.7 percent) patients had systemic disease. The 5-year survival was approximately seventy percent. CONCLUSION: Because American Join Committee of Cancer Staging will update the classification of malignant tumors (TNM) staging in the near future, and introduce mitosis as a prognostic factor, our results show the importance of such a feature. Additional studies are necessary to confirm the importance of a prognostic score as proposed herein.

Análisis de la densidad y distribución anatómica de nevos melanocíticos adquiridos, en adolescentes del estrato socioeconómico bajo de Santiago de Chile / Body distribution and density of acquired melanocytic nevi in adolescents of low socioeconomic stratus of Santiago, Chile

Background: There is an increase in the incidence of malignant melanoma in Chile. Previous studies have shown that the density and size of acquired melanocytic nevi (AMN) are a risk factor for developing malignant melanoma. Aim: To assess the number and anatomical distribution of acquired melanocytic nevi in Chilean adolescents. Material and methods: The number of AMN was counted in 30 anatomical sites in 201 Chilean school children (111 females), aged from 11 to 15 years. The number oí small AMN (2-4.9 mm) and large AMN (>5 mm ofdiameter) was determined. Results: Mean AMN number per person was 32.7 (95 percent confidence interval (CI) 30.7-42.3) in males and 29 (95 percent CI 271-38.6) in females (p =NS). Males had a higher number of AMN in the face, neck and trunk. Females had a higher number of AMN in the upper and lower limbs. Older children, adolescents with history of sunburns and with lighter skin had a higher number of total, small and large nevi. Conclusions: The average number ofAMNfound in this study is similar to that reported in the literature. The differences in site distribution between males and femalesmay be explainedby a differentsun exposurepattern.

Childhood thyroid cancer in Belarus, Russia, and Ukraine after Chernobyl and at present

Thyroid cancer in children is usually rare, but in the individuals exposed to radiation risk of disease increases considerably. After the Chernobyl accident in 1986, an over 10-fold maximal elevation in the incidence of thyroid cancer was registered about a decade later, cumulatively resulting in more than a thousand of newly diagnosed cases in children who lived in the territories of Belarus, Russia, and Ukraine affected by radioactive fallouts. Experience from the epidemic substantially promoted knowledge in clinical pediatric oncology, pathology and basic sciences. This article overviews epidemiology, clinical features, results of treatment and follow-up of childhood patients with radiation-induced Chernobyl thyroid cancer in comparison to sporadic cases diagnosed at present. In addition, we discuss general issues of pathology and molecular findings in childhood thyroid carcinomas.

O câncer de tiróide é habitualmente raro em crianças, mas em indivíduos expostos a radiação o risco da doença aumenta consideravelmente. Cerca de uma década após o acidente de Chernobil, em 1986, foi registrado um aumento de mais de 10 vezes na incidência de câncer de tiróide, resultando cumulativamente em mais de mil novos casos diagnosticados em crianças que viviam nos territórios da Bielorrússia, Russia, e Ucrânia, afetadas pela chuva radioativa. A experiência com essa epidemia resultou em conhecimento substancial de oncologia pediátrica clínica, patologia e ciências básicas. Este artigo analisa a epidemiologia, os achados clínicos, os resultados do tratamento e a evolução de pacientes pediátricos com câncer de tiróide induzido pela radiação de Chernobil, em comparação com casos esporádicos diagnosticados atualmente. Adicionalmente, serão discutidos tópicos de patologia e achados moleculares no carcinoma de tiróide infantil.

Cáncer radioinducido / Radioinduced cancer

Publications about approximately 2 million irradiated people and their death after irradiation, were reviewed. This review considers only statistically important publications. In 140.000 people exposed to environmental radiation in zones of high background and in 350.000 occupationally exposed within recommended annual doses, no excess cancer was detected. In 1,504,000 people prenatally exposed to low doses (about 1cGY) due to diagnostic radiological examinations, the rate of cancer death before 15 years of age, was similar to unexposed populations. In 195,000 exposed to high radiotherapeutic doses, a variable increase in the incidence of cancer was detected. In 825,000 people that received internal and external irradiation in Chernobyl, no increase in cancer deaths was detected until 1991. In 1993, an increased incidence of thyroid gland carcinoma was preliminarily reported. Finally, in 100,000 people irradiated at Hiroshima and Nagasaki ab excess leukemia rate was found in the group that received doses over 200 cGY

Carcinoma papilífero da tireóide: revisäo anatomopatológica / Papillory carcinoma of the thyroid: revision

O A. faz consideraçöes gerais a propósito da história natural do câncer da tireóide, em particular sobre questöes epidemiológicas e prognósticas. Por fim, discute os aspectos histopatológicos mais salientes sobre as variantes morfológicas do carcinoma papilífero

Risco de neoplasias associado ao exame de abreugrafia / the phofluorography and risk of neoplasms

Analisam-se os efeitos à saúde causados pela utilizaçäo da radiaçäo ionizante no diagnóstico médico, considerando unidades de dose, risco de neoplasias e eficácia dos exames abreugráficos