Lifetime Cancer Mortality Risks Research Articles

Lifetime exposure to rubber dusts, fumes and N-nitrosamines and cancer mortality in a cohort of British rubber workers with 49 years follow-up

ObjectivesTo quantitatively evaluate exposure-response associations between occupational exposures to rubber dust, fumes and N-nitrosamines and cancer mortality in the UK rubber industry.MethodsCompeting risk survival analyses were used to examine cancer...

Radiation Exposure and Attributable Cancer Risk in Patients With Esophageal Atresia.

Cases of esophageal carcinoma have been documented in survivors of esophageal atresia (EA). Children with EA undergo considerable amounts of diagnostic imaging and consequent radiation exposure potentially increasing their lifetime cancer mortality risk. This study evaluates the radiological procedures performed on patients with EA and estimates their cumulative radiation exposure and attributable lifetime cancer mortality risk. Medical records of patients with EA managed at a tertiary care center were reviewed for demographics, EA subtype, and number and type of radiological investigations. Existing normative data were used to estimate the cumulative radiation exposure and lifetime cancer risk per patient. The present study included 53 patients with a mean follow-up of 5.7 years. The overall median and maximum estimated effective radiation dose in the neonatal period was 5521.4 μSv/patient and 66638.6 μSv/patient, respectively. This correlates to a median and maximum estimated cumulative lifetime cancer mortality risk of 1:1530 and 1:130, respectively. Hence, radiation exposure in the neonatal period increased the cumulative cancer mortality risk a median of 130-fold and a maximum of 1575-fold in EA survivors. Children with EA are exposed to significant amounts of radiation and an increased estimated cumulative cancer mortality risk. Efforts should be made to eliminate superfluous imaging.

Analyzing overdiagnosis risk in cancer screening: A case of screening mammography for breast cancer

ABSTRACTOverdiagnosis is defined as the diagnosis of an asymptotic cancer that would not have presented clinically in a patient's lifetime in the absence of screening. Quantifying overdiagnosis is difficult, since it is impossible to distinguish between a cancer that would cause symptoms in the patient lifetime and the ones that would not. In this study, a mathematical framework is developed to estimate the lifetime overdiagnosis and cancer mortality risks associated with cancer screening policies. We also develop an optimization model to extract screening policies with minimum overdiagnosis and lifetime breast cancer mortality risk. The proposed optimization model is highly nonlinear with complex structure. Therefore, we linearize the optimization model by introducing new decision variables and restructuring the equations to solve it optimally. We utilize existing data on breast cancer for average-risk women and evaluated mammography screening policies in terms of their associated lifetime overdiagnosis and breast cancer mortality risk. Optimal policies with minimum overdiagnosis and mortality risks are derived. The optimal policies outperform the existing in-practice policies by recommending more frequent screenings at younger ages, as the cancer is more aggressive and the remaining life expectancy is higher for younger patients.

P-40: Radiation Exposure and Attributable Lifetime Cancer Mortality Risk for Patients with Esophageal Atresia

P-40: Radiation Exposure and Attributable Lifetime Cancer Mortality Risk for Patients with Esophageal Atresia

Imaging, radiation exposure, and attributable cancer risk for neonates with necrotizing enterocolitis

PurposeNeonates with necrotizing enterocolitis (NEC) receive numerous radiologic investigations that potentially increase their lifetime cancer mortality risk. We evaluated our radiologic practice pattern for patients with NEC and estimated cumulative radiation exposure and lifetime cancer risk. MethodsInfants with NEC in a tertiary care NICU had patient demographics, imaging, treatments/interventions, and outcomes analyzed over 3years. The number and type of imaging were recorded, including NEC-related imaging (thoraco-abdominal “babygrams” and abdominal radiographs), and all other imaging modalities. Patients were stratified by birth weight: group 1 (<750g); group 2 (751–1500g); and group 3 (>1501g). Pre-existing normative data were used to calculate radiation exposure, absorption, and attributable cancer risk from NEC-related imaging. ResultsSixty-four neonates with 72 episodes of NEC were identified. Overall survival was 75.0%. When stratified by birth weight, mean abdominal radiographs and babygrams comprised 51%, 60%, and 74% of total imaging, giving median mGy doses of 2.1, 0.4, and 0.2, respectively. Compared to normative data, radiation dosing, and median cumulative cancer lifetime mortality risk increased by an average of 4.3× from baseline, with two cases documenting a 20-fold increase. ConclusionNeonates with NEC are exposed to significant amounts of radiation directly attributable to disease surveillance. Non-radiologic surveillance methods could significantly reduce radiation exposure and cancer risk in these infants.

Effective dose estimation and lifetime cancer mortality risk assessment from exposure to Chernobyl 137Cs on the territory of Belgrade City and the region of Vojvodina, Serbia

The purpose of this paper is to determine the activity concentrations of radionuclide (137)Cs in soil samples on the territory of Belgrade and the province of Vojvodina. Also, the lifetime cancer mortality risk from external exposure during 1 year is assessed, and the effective dose is estimated. Eighty eight soil samples were collected from 30 uncultivated locations in Belgrade, and 30 soil samples were collected from 10 locations in the province of Vojvodina. Activity concentrations were measured using an HPGe detector. Using dose conversion factors taken from "EPA Federal Guidance Report 12," annual effective doses from external sources were estimated. The lifetime cancer mortality risk was assessed using cancer risk coefficients taken from "EPA Federal Guidance Report 13." Activity concentrations of (137)Cs for the territory of Belgrade are in the range of 2.07-89.1 Bq/kg with a mean value of 23.77 Bq/kg; the estimated annual effective doses are in the range of 0.41-17.5 nSv with a mean value of 4.67 nSv, and assessed lifetime cancer mortality risks, normalized on 100,000 inhabitants, are in the range 0.2-9.5 × 10(-5) with a mean value 2.5 × 10(-5). Activity concentrations of (137)Cs for the province of Vojvodina are in the range of 2.73-18.9 Bq/kg with a mean value of 8.57 Bq/kg; estimated annual effective doses are in the range of 0.54-3.71 nSv with a mean value of 1.68 nSv, and assessed lifetime cancer mortality risks, normalized on 100,000 inhabitants, are in the range of 0.3-2.0 × 10(-5) with a mean value 0.9 × 10(-5). Receiving doses are low from (137)Cs radionuclides occurring in soil, according to the linear no-threshold approach; the risk for cancer development exists but is very small.

Surveillance Computed Tomography Scans for Patients With Lymphoma: Is the Risk Worth the Benefits?

Concerns regarding the risks of cancer and cancer-related death as a result of radiation from computed tomography (CT) scans and the lack of data demonstrating a survival advantage for surveillance CT scans following lymphoma therapy have raised questions regarding their benefit. We compared the radiation-related lifetime cancer incidence (LCI) and mortality risks (LCMRs) associated with CT scans for staging and surveillance of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) with the cumulative probability of lymphoma death (CPLD) during surveillance. The LCI and LCMR were calculated using published estimates of the cumulative organ-specific radiation doses from full-body CT scans and sex-, age-, and organ-dependent cancer risks per 0.1 Gy provided by the Biologic Effects of Ionizing Radiations VII report. Surveillance, Epidemiology, and End Results (SEER) data were used to identify cases between 2000 and 2006 from 17 SEER registries and calculate CPLD for specified cohorts. For a 70-year-old patient, a single full-body CT examination is associated with a LCI of 0.044% and 0.057%, and a LCMR of 0.032% and 0.044% for males and females, respectively. For 20-year-old patients the LCMRs were 0.071% for men and 0.108% for women. The LCI and LCMR were lower for males and were markedly less than the CPLD at 5 years for most lymphoma subtypes, but relevant for younger women with HL. Although the LCMR from CT scans is small compared with lymphoma-related deaths for most subgroups, these data should be discussed with patients in formulating plans for surveillance following lymphoma therapy.

Head Trauma: When Is a CT Not Indicated?

Head Trauma: When Is a CT Not Indicated?

Lymphoma and Whole Body CT Scan Mortality Risk

Background: Recent concerns regarding the risks of cancer and cancer-related death due to radiation from computed tomography (CT) scans (Brenner, NEJM 2007) and the lack of data demonstrating a survival advantage for surveillance CT scans following lymphoma therapy have raised questions regarding their benefit. We compared the radiation-related lifetime cancer incidence (LCI) and mortality risks (LCMR) associated with CT scans for staging and surveillance of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) with the cumulative probability of lymphoma death (CPLD) during monitoring.Methods: Using 2008 NCCN Guidelines for HL and NHL, we estimated that the average number of scans a patient would need during 5 years of treatment and follow-up would be 10. We utilized published estimates of the cumulative organ-specific radiation doses from full-body CT scans (Brenner, Radiology 2004) and calculated the LCI and LCMR using sex-, age-, and organ-dependent cancer risks per 0.1Gy provided by the Biological Effects of Ionizing Radiations VII report. Site-specific cancer risks were summed to yield the overall LCI and LCMR as described by Brenner (Med Phys 2001). Surveillance, Epidemiology, and End Results (SEER) data were used to identify cases between 2000 and 2005 from 17 SEER Registries and calculate CPLD for specified cohorts.Results: LCI and LCMR were lower for males and were markedly less than the CPLD at 5 years for most patients, but relevant for younger women with HL given their low risk of HL death (Table 1). The relationship between LCMR and the number of CT scans is shown in Figure 1. Additional implications of surveillance strategies on specific cancer risks will be presented.Conclusion: While the LCMR from CT scans is small compared to lymphoma-related deaths for most subgroups, these data should be discussed with patients in formulating plans for surveillance following lymphoma therapy.Table 1 LCI and LCMR due to CT scans compared with CPLD for lymphoma subtypes by age at diagnosis and genderLymphoma Subtype (Age at Diagnosis)LCI from CT*LCMR from CT*5-year Cumulative Probability of Lymphoma Death**MalesFemalesMalesFemalesMalesFemalesNHL (70 yrs)0.00440.00570.00320.00440.310.28FL (70 yrs)0.220.18DLBCL (70 yrs)0.390.37HL (20 yrs)0.01330.02420.00700.01080.070.07HL (80 yrs)0.00220.00300.00190.00260.470.55* per person exposed to the cumulative radiation dose associated with 10 full-body CT scans during 5 years from diagnosis** Age group studied were HL (20–29 & 80–84), DLBCL (60–79), FL (60–79), NHL (60–79) [Display omitted]

Routine scans for lymphoma produce minimal radiation-related cancer mortality risk

17508 Background: Recent concern regarding the risks of cancer and cancer-related death due to radiation from computed tomography (CT) scans (Brenner, NEJM 2007) is accompanied by increased use of 18FDG positron emission tomography (PET) scans in lymphoma (Cheson, JCO 2007). We compared the radiation-related lifetime cancer mortality risks (LCMR) associated with CT and PET scans for staging and monitoring of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) with the probability of cancer death during this monitoring period. Methods: Using NCCN Guidelines for HL and NHL, we determined the number of scans a patient would undergo in the 5 years after diagnosis. We utilized published estimates of the cumulative organ-specific radiation doses from full-body CT scans (Brenner, Radiology 2004) and PET (Brix, J Nucl Med 2005), and calculated the lifetime cancer mortality risk (LCMR) associated with scans, using sex-, age-, and organ-dependent cancer risks per 0.1Gy provided by the Biological Effects of Ionizing Radiations VII report. Site-specific cancer risks were summed to yield the overall LCMR as described by Brenner (Med Phys 2001). To provide a comparator for the LCMRs, Surveillance, Epidemiology, and End Results data were used to identify cases between 1973 and 2004 and calculate cumulative probability of cancer death (CPCD) for the specified cohorts. Results: Since LCMR depends on gender and age at exposure, the table shows the LCMRs for CT and PET scans and CPCD for lymphoma subtypes by age at diagnosis. LCMRs were lower for males, were markedly less than the CPCD at 5-years for most lymphoma patients, but become relevant for younger women with HL undergoing CTs given their low risk of cancer death. Although PET scans are not recommended for lymphoma surveillance, they have a reduced LCMR due to less radiation exposure. Conclusions: While the LCMR from scans is small compared to cancer-related deaths for most individuals, these data should be discussed with patients in formulating plans for surveillance following lymphoma therapy. Lymphoma Subtype (Age at Diagnosis) LCMR from CT * LCMR from PET * 5-year Cumulative Probability of Cancer Death Males Females Males Females Males Females NHL (70 yrs) 0.58 0.80 0.33 0.42 46% 42% FL (70 yrs) 0.58 0.80 0.33 0.42 30% 27% DLBCL (70 yrs) 0.58 0.80 0.33 0.42 55% 53% HL (20 yrs) 1.27 1.95 0.61 0.83 13% 8% HL (80 yrs) 0.35 0.47 0.21 0.27 68% 61% * deaths per 100 persons exposed to the cumulative radiation dose associated with scans at 5 years No significant financial relationships to disclose.

Water consumption patterns in rural Bangladesh: are we underestimating total arsenic load?

Risk related to the ingestion of any water contaminants depends on many factors, including the daily per capita amount of consumed water relative to body weight. This study explored the water consumption pattern of a rural arsenic-affected population in Bangladesh. The study findings are likely to contribute to the risk estimation attributable to ingestion of arsenic and other drinking water contaminants. A total of 640 individuals participated in this cross-sectional study carried out in an arsenic-affected rural population in Bangladesh. In this study daily per capita water consumption for drinking purposes was found to be 73.04 ml/kg/d (range = 71.24–74.84 ml/kg/d), which is higher than for both the US and Taiwan populations. This difference in per capita drinking water consumption might contribute to much higher lifetime cancer mortality and other morbidity risks from arsenic among the Bangladesh population compared to either the US or Taiwan populations. Arsenic is also ingested through cooking water which, if considered, might increase the risk further. The findings of this study highlight the urgent need for a holistic water supply programme for Bangladesh, with special emphasis on the arsenic-affected population.

Estimated radiation risks potentially associated with full-body CT screening.

To estimate the radiation-related cancer mortality risks associated with single or repeated full-body computed tomographic (CT) examinations by using standard radiation risk estimation methods. The estimated dose to the lung or stomach from a single full-body CT examination is 14-21 mGy, which corresponds to a dose region for which there is direct evidence of increased cancer mortality in atomic bomb survivors. Total doses for repeated examinations are correspondingly higher. The authors used estimated cancer risks in a U.S. population derived from atomic bomb-associated cancer mortality data, together with calculated organ doses from a full-body CT examination, to estimate the radiation risks associated with single and multiple full-body CT examinations. A single full-body CT examination in a 45-year-old adult would result in an estimated lifetime attributable cancer mortality risk of around 0.08%, with the 95% credibility limits being a factor of 3.2 in either direction. A 45-year-old adult who plans to undergo annual full-body CT examinations up to age 75 (30 examinations) would accrue an overall estimated lifetime attributable risk of cancer mortality of about 1.9%, with the 95% credibility limits being a factor of 2 in either direction. The authors provide estimates of lifetime cancer mortality risks from both single and annual full-body CT examinations. These risk estimates are needed to assess the utility of full-body CT examinations from both an individual and a public health perspective.

Radiation dose and cancer risk to children undergoing skull radiography.

Limited data exist in the literature concerning the patient-effective dose from paediatric skull radiography. No information has been provided regarding organ doses, patient dose during PA skull projection, risk of cancer induction and dose to comforters, i.e. individuals supporting children during exposure. To estimate patient-effective dose, organ doses, lifetime cancer mortality risk to children and radiation dose to comforters associated with skull radiography. Data were collected from 136 paediatric examinations, including AP, PA and lateral skull radiographs. Entrance-surface dose (ESD) and dose to comforters were measured using thermoluminescent dosimeters. Patients were divided into the following age groups: 0.5-2, 3-7, 8-12 and 13-18 years. The patient-effective dose and corresponding organ doses were calculated using data from the NRPB and Monte Carlo techniques. The risk for fatal cancer induction was assessed using appropriate risk coefficients. For AP, PA and lateral skull radiography, effective dose ranges were 8.8-25.4, 8.2-27.3 and 8.4-22.7 microSv respectively, depending upon the age of the child. For each skull projection, the organs receiving doses above 10 microGy are presented. The number of fatal cancers was found to be less than or equal to 2 per 1 million children undergoing a skull radiograph. The mean radiation dose absorbed by the hands of comforters was 13.4 microGy. The current study provides detailed tabular and graphical data on ESD, effective dose, organ doses and lifetime cancer mortality risk to children associated with AP, PA and lateral skull projections at all patient ages.

Estimated risks of radiation-induced fatal cancer from pediatric CT.

In light of the rapidly increasing frequency of pediatric CT examinations, the purpose of our study was to assess the lifetime cancer mortality risks attributable to radiation from pediatric CT. Organ doses as a function of age-at-diagnosis were estimated for common CT examinations, and estimated attributable lifetime cancer mortality risks (per unit dose) for different organ sites were applied. Standard models that assume a linear extrapolation of risks from intermediate to low doses were applied. On the basis of current standard practice, the same exposures (milliampere-seconds) were assumed, independent of age. The larger doses and increased lifetime radiation risks in children produce a sharp increase, relative to adults, in estimated risk from CT. Estimated lifetime cancer mortality risks attributable to the radiation exposure from a CT in a 1-year-old are 0.18% (abdominal) and 0.07% (head)-an order of magnitude higher than for adults-although those figures still represent a small increase in cancer mortality over the natrual background rate. In the United States, of approximately 600,000 abdominal and head CT examinations annually performed in children under the age of 15 years, a rough estimate is that 500 of these individuals might ultimately die from cancer attributable to the CT radiation. The best available risk estimates suggest that pediatric CT will result in significantly increased lifetime radiation risk over adult CT, both because of the increased dose per milliampere-second, and the increased lifetime risk per unit dose. Lower milliampere-second settings can be used for children without significant loss of information. Although the risk-benefit balance is still strongly tilted toward benefit, because the frequency of pediatric CT examinations is rapidly increasing, estimates that quantitative lifetime radiation risks for children undergoing CT are not negligible may stimulate more active reduction of CT exposure settings in pediatric patients.

Application of “Four-step analgesic ladder” in the treatment of cancer-related pain — Analysis of 251 cases

Concerns regarding the risks of cancer and cancer-related death as a result of radiation from computed tomography (CT) scans and the lack of data demonstrating a survival advantage for surveillance CT scans following lymphoma therapy have raised questions regarding their benefit. We compared the radiation-related lifetime cancer incidence (LCI) and mortality risks (LCMRs) associated with CT scans for staging and surveillance of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) with the cumulative probability of lymphoma death (CPLD) during surveillance.The LCI and LCMR were calculated using published estimates of the cumulative organ-specific radiation doses from full-body CT scans and sex-, age-, and organ-dependent cancer risks per 0.1 Gy provided by the Biologic Effects of Ionizing Radiations VII report. Surveillance, Epidemiology, and End Results (SEER) data were used to identify cases between 2000 and 2006 from 17 SEER registries and calculate CPLD for specified cohorts.For a 70-year-old patient, a single full-body CT examination is associated with a LCI of 0.044% and 0.057%, and a LCMR of 0.032% and 0.044% for males and females, respectively. For 20-year-old patients the LCMRs were 0.071% for men and 0.108% for women. The LCI and LCMR were lower for males and were markedly less than the CPLD at 5 years for most lymphoma subtypes, but relevant for younger women with HL.Although the LCMR from CT scans is small compared with lymphoma-related deaths for most subgroups, these data should be discussed with patients in formulating plans for surveillance following lymphoma therapy.