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1.
Br J Cancer ; 112(1): 44-51, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25349972

RESUMO

BACKGROUND: Abdominal radiotherapy for testicular cancer (TC) increases risk for second stomach cancer, although data on the radiation dose-response relationship are sparse. METHODS: In a cohort of 22,269 5-year TC survivors diagnosed during 1959-1987, doses to stomach subsites were estimated for 92 patients who developed stomach cancer and 180 matched controls. Chemotherapy details were recorded. Odds ratios (ORs) were estimated using logistic regression. RESULTS: Cumulative incidence of second primary stomach cancer was 1.45% at 30 years after TC diagnosis. The TC survivors who received radiotherapy (87 (95%) cases, 151 (84%) controls) had a 5.9-fold (95% confidence interval (CI) 1.7-20.7) increased risk of stomach cancer. Risk increased with increasing stomach dose (P-trend<0.001), with an OR of 20.5 (3.7-114.3) for ⩾50.0 Gy compared with <10 Gy. Radiation-related risks remained elevated ⩾20 years after exposure (P<0.001). Risk after any chemotherapy was not elevated (OR=1.1; 95% CI 0.5-2.5; 14 cases and 23 controls). CONCLUSIONS: Radiotherapy for TC involving parts of the stomach increased gastric cancer risk for several decades, with the highest risks after stomach doses of ⩾30 Gy. Clinicians should be aware of these excesses when previously irradiated TC survivors present with gastrointestinal symptoms and when any radiotherapy is considered in newly diagnosed TC patients.


Assuntos
Neoplasias Induzidas por Radiação/etiologia , Neoplasias Gástricas/etiologia , Neoplasias Testiculares/radioterapia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Relação Dose-Resposta à Radiação , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Sobreviventes , Adulto Jovem
2.
Br J Cancer ; 110(10): 2623-32, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24755883

RESUMO

BACKGROUND: Retinoblastoma is a rare childhood eye cancer caused by germline or somatic mutations in the RB1 gene. Previous studies observed elevated breast cancer risk among retinoblastoma survivors. However, there has been no research on breast cancer risk in relation to radiation (primarily scatter radiation from the primary treatment) and genetic susceptibility of retinoblastoma survivors. METHODS: Two groups of retinoblastoma survivors from the US and UK were selected, and breast cancer risk analysed using a case-control methodology, nesting within the respective cohorts, matching on heritability (that is to say, having bilateral retinoblastoma or being unilateral cases with at least one relative with retinoblastoma), and using exact statistical methods. There were a total of 31 cases and 77 controls. RESULTS: Overall there was no significant variation of breast cancer risk with dose (P>0.5). However, there was a pronounced and significant (P=0.047) increase in the risk of breast cancer with increasing radiation dose for non-heritable retinoblastoma patients and a slight and borderline significant (P=0.072) decrease in risk of breast cancer with increasing radiation dose for heritable retinoblastoma patients, implying significant (P=0.024) heterogeneity in radiation risk between the heritable and non-heritable retinoblastoma groups; this was unaffected by the blindness status. There was no significant effect of any type of alkylating-agent chemotherapy on breast cancer risk (P>0.5). CONCLUSIONS: There is significant radiation-related risk of breast cancer for non-heritable retinoblastoma survivors but no excess risk for heritable retinoblastoma survivors, and no significant risk overall. However, these results are based on very small numbers of cases; therefore, they must be interpreted with caution.


Assuntos
Neoplasias da Mama/etiologia , Neoplasias Oculares/radioterapia , Neoplasias Induzidas por Radiação/etiologia , Retinoblastoma/radioterapia , Adolescente , Adulto , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama Masculina/epidemiologia , Neoplasias da Mama Masculina/etiologia , Neoplasias da Mama Masculina/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Relação Dose-Resposta à Radiação , Neoplasias Oculares/genética , Feminino , Genes do Retinoblastoma , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/epidemiologia , Neoplasias Induzidas por Radiação/epidemiologia , Radioterapia/efeitos adversos , Retinoblastoma/genética , Estudos Retrospectivos , Risco , Tamanho da Amostra , Método Simples-Cego , Sobreviventes , Reino Unido/epidemiologia , Estados Unidos/epidemiologia , Adulto Jovem
3.
Ann Oncol ; 25(10): 2073-2079, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25185241

RESUMO

BACKGROUND: Although elevated risks of pancreatic cancer have been observed in long-term survivors of Hodgkin lymphoma (HL), no prior study has assessed the risk of second pancreatic cancer in relation to radiation dose and specific chemotherapeutic agents. PATIENTS AND METHODS: We conducted an international case-control study within a cohort of 19 882 HL survivors diagnosed from 1953 to 2003 including 36 cases and 70 matched controls. RESULTS: Median ages at HL and pancreatic cancer diagnoses were 47 and 60.5 years, respectively; median time to pancreatic cancer was 19 years. Pancreatic cancer risk increased with increasing radiation dose to the pancreatic tumor location (Ptrend = 0.005) and increasing number of alkylating agent (AA)-containing cycles of chemotherapy (Ptrend = 0.008). The odds ratio (OR) for patients treated with both subdiaphragmatic radiation (≥10 Gy) and ≥6 AA-containing chemotherapy cycles (13 cases, 6 controls) compared with patients with neither treatment was 17.9 (95% confidence interval 3.5-158). The joint effect of these two treatments was significantly greater than additive (P = 0.041) and nonsignificantly greater than multiplicative (P = 0.29). Especially high risks were observed among patients receiving ≥8400 mg/m(2) of procarbazine with nitrogen mustard or ≥3900 mg/m(2) of cyclophosphamide. CONCLUSION: Our study demonstrates for the first time that both radiotherapy and chemotherapy substantially increase pancreatic cancer risks among HL survivors treated in the past. These findings extend the range of nonhematologic cancers associated with chemotherapy and add to the evidence that the combination of radiotherapy and chemotherapy can lead to especially large risks.


Assuntos
Doença de Hodgkin/complicações , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/etiologia , Adulto , Idoso , Estudos de Casos e Controles , Relação Dose-Resposta à Radiação , Feminino , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/patologia , Neoplasias Pancreáticas/induzido quimicamente , Radioterapia/efeitos adversos , Fatores de Risco
4.
Ann Oncol ; 23(12): 3081-3091, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22745217

RESUMO

BACKGROUND: Radiotherapy for breast cancer may expose the esophagus to ionizing radiation, but no study has evaluated esophageal cancer risk after breast cancer associated with radiation dose or systemic therapy use. DESIGN: Nested case-control study of esophageal cancer among 289 748 ≥5-year survivors of female breast cancer from five population-based cancer registries (252 cases, 488 individually matched controls), with individualized radiation dosimetry and information abstracted from medical records. RESULTS: The largest contributors to esophageal radiation exposure were supraclavicular and internal mammary chain treatments. Esophageal cancer risk increased with increasing radiation dose to the esophageal tumor location (P(trend )< 0.001), with doses of ≥35 Gy associated with an odds ratio (OR) of 8.3 [95% confidence interval (CI) 2.7-28]. Patients with hormonal therapy ≤5 years preceding esophageal cancer diagnosis had lower risk (OR = 0.4, 95% CI 0.2-0.8). Based on few cases, alkylating agent chemotherapy did not appear to affect risk. Our data were consistent with a multiplicative effect of radiation and other esophageal cancer risk factors (e.g. smoking). CONCLUSIONS: Esophageal cancer is a radiation dose-related complication of radiotherapy for breast cancer, but absolute risk is low. At higher esophageal doses, the risk warrants consideration in radiotherapy risk assessment and long-term follow-up.


Assuntos
Intervalo Livre de Doença , Neoplasias Esofágicas/mortalidade , Neoplasias Induzidas por Radiação/etiologia , Segunda Neoplasia Primária/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas , Índice de Massa Corporal , Neoplasias da Mama/radioterapia , Estudos de Casos e Controles , Relação Dose-Resposta à Radiação , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/tratamento farmacológico , Neoplasias Induzidas por Radiação/radioterapia , Segunda Neoplasia Primária/tratamento farmacológico , Segunda Neoplasia Primária/radioterapia , Dosagem Radioterapêutica , Risco , Fatores de Risco , Fumar , Sobreviventes
5.
Soc Secur Bull ; 64(1): 52-83, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12428518

RESUMO

This article analyzes the impact of policy variables--employer accommodations, state Social Security Disability Insurance (DI) allowance rates, and DI benefits--on the timing of an application for DI benefits by workers with a work-limiting health condition starting when their health condition first begins to bother them. The analysis uses a rich mixture of personal and employer characteristics from the Health and Retirement Study linked to Social Security administrative records. We find that most workers do not apply immediately for DI benefits when they are first bothered by a health condition. On the contrary, the median working-age man with a work-limiting condition waits 7 years after that time before applying, and the median working-age woman waits 8 years. Although the risk of applying for benefits is greatest in the year following onset, only 16 percent of men and 13 percent of women in our sample apply within the first year, and the risk of application falls thereafter. That finding suggests that institutional factors, in addition to health factors, may play a role in the timing of DI applications. Using kernel density estimates of the distribution of application and nonapplication ordered by state allowance rates (the rate of acceptance per DI determination in each state), we find that both men and women who live in states with high allowance rates are disproportionately more likely to apply for benefits in the first year after their condition begins to bother them than are those in states with low allowance rates. Using life-table analysis, we also find that men and women who are accommodated by their employers are significantly less likely to apply for DI benefits in each of the first few years after their condition begins to bother them than are those who are not accommodated. On the basis of this evidence, we include these policy variables in a model of the timing of DI application that controls for other socioeconomic variables as well as health. Using a hazard model, we find that workers who live in states with higher allowance rates apply for DI benefits significantly sooner than those living in states with lower allowance rates following the onset of a work-limiting health condition. Workers who are accommodated following the onset of a work-limiting health condition, however, are significantly slower to apply for DI benefits. Using the mean values of all explanatory variables, we estimate the relative importance of changes in these policy variables on the speed with which workers apply for benefits after onset. We find that the mean time until application for men is 10.22 years. Universal accommodations following onset would delay application by 4.36 years. In contrast, a 20 percent decrease in state allowance rates would delay application by only 0.88 years. For working-age women, the average expected time until application once a condition begins to bother them is 10.58 years. Universal accommodations would delay that by 3.76 years, and a 20 percent decrease in allowance rates would delay it by 1.47 years. A complication in this analysis is that the policy variables are to some degree endogenous. Accommodation is probably offered more often to workers who want to continue working. Allowance rates are chosen by states on the basis of federal policy and local choices and probably in part on the health condition of workers in the state. Therefore, our estimates are upper bounds of these policy effects. Still, we believe we provide evidence that the social environment faced by workers with work-limiting health conditions can significantly influence their decision to apply for DI benefits, holding their specific health conditions constant.


Assuntos
Tomada de Decisões , Benefícios do Seguro , Seguro por Deficiência/estatística & dados numéricos , Política Organizacional , Previdência Social/estatística & dados numéricos , Adulto , Análise de Variância , Definição da Elegibilidade , Feminino , Humanos , Tábuas de Vida , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Tempo , Estados Unidos
6.
Radiol Technol ; 46(4): 279-81, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1110983

RESUMO

In cranial angiography it has always been difficult to visualize extracranial vessels of the cervico-thoracic region, upon one radiograph, by using the same exposure factors for both regions. For this reason, we experimented and found that by applying a dry cornmeal bolus on specific areas of the neck a technically superior radiograph of these regions can be achieved. This bolus simulated added soft tissue to the cervical region. The density of the cervical region is now similar to that of the upper thoracic. As a result, factors set for one exposure will adequately penetrate both areas.


Assuntos
Angiografia Cerebral/métodos , Humanos , Pescoço , Tecnologia Radiológica/métodos , Zea mays
7.
Radiol Technol ; 47(6): 385-9, 1976.
Artigo em Inglês | MEDLINE | ID: mdl-951504

RESUMO

Double contrast arthrography of the knee is the method of choice for visualization of the menisci, while the single positive contrast technique is the preferred method for evaluation of the cruciate ligaments. A technique is described which combines the advantages of these two methods. Following radiography of the menisci, an essentially single positive contrast study of the cruciate ligaments is obtained by positioning the patient in the lateral recumbent position with the knee flexed to about 90degree. The positive contrast medium in this position fills the joint cavity beyond its mid-point and surrounds the cruciate ligaments. Tomographic studies of the midline of the knee joint, made in this position with a polytome unit, demonstrate the cruciate ligaments to best advantage.


Assuntos
Articulação do Joelho/diagnóstico por imagem , Ligamentos/diagnóstico por imagem , Tomografia por Raios X/métodos , Humanos
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