RESUMO
BACKGROUND: Lung cancer screening with annual chest computed tomography (CT) is recommended for current and former smokers with a ≥30-pack-year smoking history. Patients with chronic obstructive pulmonary disease (COPD) are at increased risk of developing lung cancer and may benefit from screening at lower pack-year thresholds. METHODS: We used a previously validated simulation model to compare the health benefits of lung cancer screening in current and former smokers ages 55-80 with ≥30 pack-years with hypothetical programs using lower pack-year thresholds for individuals with COPD (≥20, ≥10, and ≥1 pack-years). Calibration targets for COPD prevalence and associated lung cancer risk were derived using the Framingham Offspring Study limited data set. We performed sensitivity analyses to evaluate the stability of results across different rates of adherence to screening, increased competing mortality risk from COPD, and increased surgical ineligibility in individuals with COPD. The primary outcome was projected life expectancy. RESULTS: Programs using lower pack-year thresholds for individuals with COPD yielded the highest life expectancy gains for a given number of screens. Highest life expectancy was achieved when lowering the pack-year threshold to ≥1 pack-year for individuals with COPD, which dominated all other screening strategies. These results were stable across different adherence rates to screening and increases in competing mortality risk for COPD and surgical ineligibility. CONCLUSIONS: Current and former smokers with COPD may disproportionately benefit from lung cancer screening. A lower pack-year threshold for screening eligibility may benefit this high-risk patient population.
Assuntos
Simulação por Computador/estatística & dados numéricos , Técnicas de Apoio para a Decisão , Detecção Precoce de Câncer , Neoplasias Pulmonares/diagnóstico , Programas de Rastreamento , Medicina de Precisão , Doença Pulmonar Obstrutiva Crônica/complicações , Fumar/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Detecção Precoce de Câncer/tendências , Feminino , Humanos , Expectativa de Vida , Neoplasias Pulmonares/fisiopatologia , Neoplasias Pulmonares/prevenção & controle , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Programas de Rastreamento/tendências , Pessoa de Meia-Idade , Medicina de Precisão/métodos , Medicina de Precisão/normas , Medicina de Precisão/tendências , Prevalência , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Ventilação Pulmonar , Medição de Risco , Fatores de Risco , Espirometria , Tomografia Computadorizada por Raios X , Estados Unidos/epidemiologiaRESUMO
OBJECTIVE: The purpose of this article is to evaluate whether examination-specific radiation dose metrics reliably measure an institution's success in reducing cancer risks. MATERIALS AND METHODS: We projected health benefits from dose-reduction programs in a hypothetical institution that sought to decrease exposures from abdominopelvic CT. Using modeling techniques to project radiation-induced cancer risks and tertiary center data to inform the institution's abdominopelvic CT age distribution, we compared a program in which effective doses were reduced equally (from 10 to 7 mSv) across all scans with programs in which dose reduction was age dependent. For each program, we projected lethal cancers averted, life expectancy gained, and average institutional dose achieved. Markov Chain Monte Carlo methods were used to estimate uncertainty in projections. RESULTS: The analysis's age distribution drew from 20,979 CT scans; 39% were from patients 65 years old and older. To illustrate trends yielded, if all patients in the hypothetical institution underwent 7-mSv (instead of 10-mSv) scans, we projected the maximum number of lethal cancers averted to be seven per 100,000 patients, and maximum life expectancy gained to be 0.26 days per patient, when averaged over the institution's population. When restricting dose reduction (from 10 to 7 mSv) to patients younger than 65 years, benefits were slightly lower (five lethal cancers averted per 100,000 patients and 0.22 days per patient gained); however, the average institutional dose was substantially higher (8.2 mSv). Although dose reduction in patients 65 years old and older accounted for only 16% of possible institutional life expectancy gains, this patient group contributed disproportionately (39%) to the institution's average dose. CONCLUSION: Institutional examination-specific dose metrics can be misleading, because the least-benefited patients may contribute disproportionately toward "improved" averages.
Assuntos
Benchmarking , Assistência Centrada no Paciente , Doses de Radiação , Tomografia Computadorizada por Raios X/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Neoplasias/prevenção & controle , Medição de Risco , Gestão de Riscos , Tomografia Computadorizada por Raios X/efeitos adversos , Adulto JovemRESUMO
BACKGROUND: Current clinical guidelines recommend earlier, more intensive breast cancer screening with both magnetic resonance imaging (MRI) and mammography for women with breast cancer susceptibility gene (BRCA) mutations. Unspecified details of screening schedules are a challenge for implementing guidelines. METHODS: A Markov Monte Carlo computer model was used to simulate screening in asymptomatic women who were BRCA1 and BRCA2 mutation carriers. Three dual-modality strategies were compared with digital mammography (DM) alone: 1) DM and MRI alternating at 6-month intervals beginning at age 25 years (Alt25), 2) annual MRI beginning at age 25 years with alternating DM added at age 30 years (MRI25/Alt30), and 3) DM and MRI alternating at 6-month intervals beginning at age 30 years (Alt30). Primary outcomes were quality-adjusted life years (QALYs), lifetime costs (in 2010 US dollars), and incremental cost-effectiveness (dollars per QALY gained). Additional outcomes included potential harms of screening, and lifetime costs stratified into component categories (screening and diagnosis, treatment, mortality, and patient time costs). RESULTS: All 3 dual-modality screening strategies increased QALYs and costs. Alt30 screening had the lowest incremental costs per additional QALY gained (BRCA1, $74,200 per QALY; BRCA2, $215,700 per QALY). False-positive test results increased substantially with dual-modality screening and occurred more frequently in BRCA2 carriers. Downstream savings in both breast cancer treatment and mortality costs were outweighed by increases in up-front screening and diagnosis costs. The results were influenced most by estimates of breast cancer risk and MRI costs. CONCLUSIONS: Alternating MRI and DM screening at 6-month intervals beginning at age 30 years was identified as a clinically effective approach to applying current guidelines, and was more cost-effective in BRCA1 gene mutation carriers compared with BRCA2 gene mutation carriers.