The Impact of Model Assumptions on Personalized Lung Cancer Screening Recommendations.

BACKGROUND: Recommendations regarding personalized lung cancer screening are being informed by natural-history modeling. Therefore, understanding how differences in model assumptions affect model-based personalized screening recommendations is essential. DESIGN: Five Cancer Intervention and Surveillance Modeling Network (CISNET) models were evaluated. Lung cancer incidence, mortality, and stage distributions were compared across 4 theoretical scenarios to assess model assumptions regarding 1) sojourn times, 2) stage-specific sensitivities, and 3) screening-induced lung cancer mortality reductions. Analyses were stratified by sex and smoking behavior. RESULTS: Most cancers had sojourn times <5 y (model range [MR]; lowest to highest value across models: 83.5%-98.7% of cancers). However, cancer aggressiveness still varied across models, as demonstrated by differences in proportions of cancers with sojourn times <2 y (MR: 42.5%-64.6%) and 2 to 4 y (MR: 28.8%-43.6%). Stage-specific sensitivity varied, particularly for stage I (MR: 31.3%-91.5%). Screening reduced stage IV incidence in most models for 1 y postscreening; increased sensitivity prolonged this period to 2 to 5 y. Screening-induced lung cancer mortality reductions among lung cancers detected at screening ranged widely (MR: 14.6%-48.9%), demonstrating variations in modeled treatment effectiveness of screen-detected cases. All models assumed longer sojourn times and greater screening-induced lung cancer mortality reductions for women. Models assuming differences in cancer epidemiology by smoking behaviors assumed shorter sojourn times and lower screening-induced lung cancer mortality reductions for heavy smokers. CONCLUSIONS: Model-based personalized screening recommendations are primarily driven by assumptions regarding sojourn times (favoring longer intervals for groups more likely to develop less aggressive cancers), sensitivity (higher sensitivities favoring longer intervals), and screening-induced mortality reductions (greater reductions favoring shorter intervals). IMPLICATIONS: Models suggest longer screening intervals may be feasible and benefits may be greater for women and light smokers. HIGHLIGHTS: Natural-history models are increasingly used to inform lung cancer screening, but causes for variations between models are difficult to assess.This is the first evaluation of these causes and their impact on personalized screening recommendations through easily interpretable metrics.Models vary regarding sojourn times, stage-specific sensitivities, and screening-induced lung cancer mortality reductions.Model outcomes were similar in predicting greater screening benefits for women and potentially light smokers. Longer screening intervals may be feasible for women and light smokers.

Pack-Year Smoking History: An Inadequate and Biased Measure to Determine Lung Cancer Screening Eligibility.

PURPOSE: Pack-year smoking history is an imperfect and biased measure of cumulative tobacco exposure. The use of pack-year smoking history to determine lung cancer screening eligibility in the current US Preventive Services Task Force (USPSTF) guideline may unintentionally exclude many high-risk individuals, especially those from racial and ethnic minority groups. It is unclear whether using a smoking duration cutoff instead of a smoking pack-year cutoff would improve the selection of individuals for screening. METHODS: We analyzed 49,703 individuals with a smoking history from the Southern Community Cohort Study (SCCS) and 22,126 individuals with a smoking history from the Black Women's Health Study (BWHS) to assess eligibility for screening under the USPSTF guideline versus a proposed guideline that replaces the ≥20-pack-year criterion with a ≥20-year smoking duration criterion. RESULTS: Under the USPSTF guideline, only 57.6% of Black patients with lung cancer in the SCCS would have qualified for screening, whereas a significantly higher percentage of White patients with lung cancer (74.0%) would have qualified (P < .001). Under the proposed guideline, the percentage of Black and White patients with lung cancer who would have qualified for screening increased to 85.3% and 82.0%, respectively, eradicating the disparity in screening eligibility between the groups. In the BWHS, using a 20-year smoking duration cutoff instead of a 20-pack-year cutoff increased the percentage of Black women with lung cancer who would have qualified for screening from 42.5% to 63.8%. CONCLUSION: Use of a 20-year smoking duration cutoff instead of a 20-pack-year cutoff greatly increases the proportion of patients with lung cancer who would qualify for screening and eliminates the racial disparity in screening eligibility between Black versus White individuals; smoking duration has the added benefit of being easier to calculate and being a more precise assessment of smoking exposure compared with pack-year smoking history.

Unspoken Truths: Mental Health Among Academic Surgeons.

OBJECTIVE: To characterize the current state of mental health within the surgical workforce in the United States. BACKGROUND: Mental illness and suicide is a growing concern in the medical community; however, the current state is largely unknown. METHODS: Cross-sectional survey of the academic surgery community assessing mental health, medical error, and suicidal ideation. The odds of suicidal ideation adjusting for sex, prior mental health diagnosis, and validated scales screening for depression, anxiety, post-traumatic stress disorder (PTSD), and alcohol use disorder were assessed. RESULTS: Of 622 participating medical students, trainees, and surgeons (estimated response rate=11.4%-14.0%), 26.1% (141/539) reported a previous mental health diagnosis. In all, 15.9% (83/523) of respondents screened positive for current depression, 18.4% (98/533) for anxiety, 11.0% (56/510) for alcohol use disorder, and 17.3% (36/208) for PTSD. Medical error was associated with depression (30.7% vs. 13.3%, P <0.001), anxiety (31.6% vs. 16.2%, P =0.001), PTSD (12.8% vs. 5.6%, P =0.018), and hazardous alcohol consumption (18.7% vs. 9.7%, P =0.022). Overall, 13.2% (73/551) of respondents reported suicidal ideation in the past year and 9.6% (51/533) in the past 2 weeks. On adjusted analysis, a previous history of a mental health disorder (aOR: 1.97, 95% CI: 1.04-3.65, P =0.033) and screening positive for depression (aOR: 4.30, 95% CI: 2.21-8.29, P <0.001) or PTSD (aOR: 3.93, 95% CI: 1.61-9.44, P =0.002) were associated with increased odds of suicidal ideation over the past 12 months. CONCLUSIONS: Nearly 1 in 7 respondents reported suicidal ideation in the past year. Mental illness and suicidal ideation are significant problems among the surgical workforce in the United States.

Risk Model-Based Lung Cancer Screening : A Cost-Effectiveness Analysis.

BACKGROUND: In their 2021 lung cancer screening recommendation update, the U.S. Preventive Services Task Force (USPSTF) evaluated strategies that select people based on their personal lung cancer risk (risk model-based strategies), highlighting the need for further research on the benefits and harms of risk model-based screening. OBJECTIVE: To evaluate and compare the cost-effectiveness of risk model-based lung cancer screening strategies versus the USPSTF recommendation and to explore optimal risk thresholds. DESIGN: Comparative modeling analysis. DATA SOURCES: National Lung Screening Trial; Surveillance, Epidemiology, and End Results program; U.S. Smoking History Generator. TARGET POPULATION: 1960 U.S. birth cohort. TIME HORIZON: 45 years. PERSPECTIVE: U.S. health care sector. INTERVENTION: Annual low-dose computed tomography in risk model-based strategies that start screening at age 50 or 55 years, stop screening at age 80 years, with 6-year risk thresholds between 0.5% and 2.2% using the PLCOm2012 model. OUTCOME MEASURES: Incremental cost-effectiveness ratio (ICER) and cost-effectiveness efficiency frontier connecting strategies with the highest health benefit at a given cost. RESULTS OF BASE-CASE ANALYSIS: Risk model-based screening strategies were more cost-effective than the USPSTF recommendation and exclusively comprised the cost-effectiveness efficiency frontier. Among the strategies on the efficiency frontier, those with a 6-year risk threshold of 1.2% or greater were cost-effective with an ICER less than $100 000 per quality-adjusted life-year (QALY). Specifically, the strategy with a 1.2% risk threshold had an ICER of $94 659 (model range, $72 639 to $156 774), yielding more QALYs for less cost than the USPSTF recommendation, while having a similar level of screening coverage (person ever-screened 21.7% vs. USPSTF's 22.6%). RESULTS OF SENSITIVITY ANALYSES: Risk model-based strategies were robustly more cost-effective than the 2021 USPSTF recommendation under varying modeling assumptions. LIMITATION: Risk models were restricted to age, sex, and smoking-related risk predictors. CONCLUSION: Risk model-based screening is more cost-effective than the USPSTF recommendation, thus warranting further consideration. PRIMARY FUNDING SOURCE: National Cancer Institute (NCI).

Assessing Bias and Limitations of Clinical Validation Studies of Molecular Diagnostic Tests for Indeterminate Thyroid Nodules: Systematic Review and Meta-Analysis.

Background: Molecular tests for thyroid nodules with indeterminate fine needle aspiration results are increasingly used in clinical practice; however, true diagnostic summaries of these tests are unknown. A systematic review and meta-analysis were completed to (1) evaluate the accuracy of commercially available molecular tests for malignancy in indeterminate thyroid nodules and (2) quantify biases and limitations in studies that validate those tests. Summary: PubMed, EMBASE, and Web of Science were systematically searched through July 2021. English language articles that reported original clinical validation attempts of molecular tests for indeterminate thyroid nodules were included if they reported counts of true-negative, true-positive, false-negative, and false-positive results. We performed screening and full-text review, followed by assessment of eight common biases and limitations, extraction of diagnostic and histopathological information, and meta-analysis of clinical validity using a bivariate linear mixed-effects model. Forty-nine studies were included. Meta-analysis of Afirma Gene expression classifiers (GEC; n = 38 studies) revealed a sensitivity of 0.92 (confidence interval: 0.90-0.94), specificity of 0.26 (0.20-0.32), negative likelihood ratio (LR-) of 0.32 (0.23-0.44), positive LR+ of 1.24 (1.15-1.35), and area under the curve (AUC) of 0.83 (0.74-0.89). Afirma Genomic Sequencing Classifier (GSC; n = 10) had a sensitivity of 0.94 (0.89-0.96), specificity of 0.38 (0.27-0.50), LR- of 0.18 (0.10-0.30), LR+ of 1.52 (1.28-1.87), and AUC of 0.91 (0.62-0.92). ThyroSeq v1 and v2 (n = 10) had a sensitivity of 0.86 (0.82-0.90), specificity of 0.74 (0.59-0.85), LR- of 0.19 (0.13-0.26), LR+ of 3.52 (2.08-5.92), and AUC of 0.86 (0.81-0.90). ThyroSeq v3 (n = 6) had a sensitivity of 0.92 (0.86-0.95), specificity of 0.41 (0.18-0.69), LR- of 0.24 (0.09-0.62), LR+ of 1.67 (1.09-2.98), and AUC of 0.90 (0.63-0.92). Fourteen percent of studies conducted a blinded histopathologic review of excised thyroid nodules, and 8% made the decision to go to surgery blind to molecular test results. Conclusions: Meta-analyses reveal a high diagnostic accuracy of molecular tests for thyroid nodule assessment of malignancy risk; however, these studies are subject to several limitations. Limitations and their potential clinical impacts must be addressed and, when feasible, adjusted for using valid statistical methodologies.

Cost-effectiveness Evaluation of the 2021 US Preventive Services Task Force Recommendation for Lung Cancer Screening.

IMPORTANCE: The US Preventive Services Task Force (USPSTF) issued its 2021 recommendation on lung cancer screening, which lowered the starting age for screening from 55 to 50 years and the minimum cumulative smoking exposure from 30 to 20 pack-years relative to its 2013 recommendation. Although costs are expected to increase because of the expanded screening eligibility criteria, it is unknown whether the new guidelines for lung cancer screening are cost-effective. OBJECTIVE: To evaluate the cost-effectiveness of the 2021 USPSTF recommendation for lung cancer screening compared with the 2013 recommendation and to explore the cost-effectiveness of 6 alternative screening strategies that maintained a minimum cumulative smoking exposure of 20 pack-years and an ending age for screening of 80 years but varied the starting ages for screening (50 or 55 years) and the number of years since smoking cessation (≤15, ≤20, or ≤25). DESIGN, SETTING, AND PARTICIPANTS: A comparative cost-effectiveness analysis using 4 independently developed microsimulation models that shared common inputs to assess the population-level health benefits and costs of the 2021 recommended screening strategy and 6 alternative screening strategies compared with the 2013 recommended screening strategy. The models simulated a 1960 US birth cohort. Simulated individuals entered the study at age 45 years and were followed up until death or age 90 years, corresponding to a study period from January 1, 2005, to December 31, 2050. EXPOSURES: Low-dose computed tomography in lung cancer screening programs with a minimum cumulative smoking exposure of 20 pack-years. MAIN OUTCOMES AND MEASURES: Incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year (QALY) of the 2021 vs 2013 USPSTF lung cancer screening recommendations as well as 6 alternative screening strategies vs the 2013 USPSTF screening strategy. Strategies with a mean ICER lower than $100 000 per QALY were deemed cost-effective. RESULTS: The 2021 USPSTF recommendation was estimated to be cost-effective compared with the 2013 recommendation, with a mean ICER of $72 564 (range across 4 models, $59 493-$85 837) per QALY gained. The 2021 recommendation was not cost-effective compared with 6 alternative strategies that used the 20 pack-year criterion. Strategies associated with the most cost-effectiveness included those that expanded screening eligibility to include a greater number of former smokers who had not smoked for a longer duration (ie, ≤20 years and ≤25 years since smoking cessation vs ≤15 years since smoking cessation). In particular, the strategy that screened former smokers who quit within the past 25 years and began screening at age 55 years was associated with screening coverage closest to that of the 2021 USPSTF recommendation yet yielded greater cost-effectiveness, with a mean ICER of $66 533 (range across 4 models, $55 693-$80 539). CONCLUSIONS AND RELEVANCE: This economic evaluation found that the 2021 USPSTF recommendation for lung cancer screening was cost-effective; however, alternative screening strategies that maintained a minimum cumulative smoking exposure of 20 pack-years but included individuals who quit smoking within the past 25 years may be more cost-effective and warrant further evaluation.

Trends in Thyroid Surgery and Guideline-Concordant Care in the United States, 2007-2018.

Background: The American Thyroid Association (ATA) published the 2015 Management Guidelines for patients with thyroid nodules and differentiated thyroid cancer, recommending a shift to less aggressive diagnostic, surgical, and postoperative treatment strategies. At the same time and perhaps related to the new guidelines, there has been a shift to outpatient thyroid surgery. The aim of the current study was to assess physician adherence to these recommendations by identifying and quantifying temporal trends in the rates and indications for thyroid procedures in the inpatient and outpatient settings. Methods: Using the IBM® MarketScan® Commercial database, we identified employer-insured patients in the United States who underwent outpatient and inpatient thyroid surgery from 2007 to 2018. Thyroid surgery was classified as total thyroidectomy (TT), thyroid lobectomy (TL), or a completion thyroidectomy. The surgical indication diagnosis was also determined and classified as either benign or malignant thyroid disease. We compared outpatient and inpatient trends in surgery between benign and malignant thyroid disease both before and after the release of the 2015 ATA guidelines. Results: A total of 220,088 patients who underwent thyroid surgery were included in the analysis. Approximately 80% of TLs were performed in the outpatient setting versus 70% of TTs. Longitudinal analysis showed a statistically significant changepoint for TT proportion occurring in November 2015. The proportion of TT as compared with TL decreased from 80% in September 2015 to 39% by December 2018. For thyroid cancer, there is an increasing trend in performing TL over TT, increasing from 17% in 2015 to 28% by the end of 2018. Conclusions: There was a significant changepoint occurring in November 2015 in the operative and management trends for benign and malignant thyroid disease.

Music during image-guided breast biopsy reduces patient anxiety levels.

PURPOSE: Interventions to decrease anxiety associated with image-guided breast biopsy are needed. Music intervention has been shown to be helpful in other outpatient procedural settings but data are limited regarding its effectiveness in the setting of breast biopsy. The purpose of this study was to determine whether listening to self-selected music during image-guided breast biopsy lowers anxiety. MATERIALS AND METHODS: This randomized controlled trial was approved by the institutional review board and was HIPAA-compliant. 157 women between 18 and 75 (mean, 49.7 years) years of age, undergoing stereotactic or ultrasound-guided core biopsy, were enrolled in the study and were prospectively randomized to music or usual care. Patients in the music group listened to music of their choice during the biopsy. All patients completed the State Trait Anxiety Inventory (STAI) before and after the biopsy. Differences in pre-biopsy and post-biopsy anxiety levels were compared between the two groups using the Mann-Whitney U test. RESULTS: Baseline trait anxiety scores in the two groups were similar (34.0 music, 31.5 control, p = .11). Patients in both groups showed lower state anxiety levels after the biopsy (45.6 to 34.3 music, 41.0 to 33.8 control, p < .001 for both). Patients who listened to music showed a greater reduction in anxiety (mean decrease 11.2 music, 7.3 control, p = .03). Post-biopsy anxiety levels were similar to normative values for working women in the same age group. CONCLUSION: Listening to self-selected music reduces anxiety in patients undergoing breast biopsy.

Breast cancer risk, worry, and anxiety: Effect on patient perceptions of false-positive screening results.

OBJECTIVE: The impact of mammography screening recall on quality-of-life (QOL) has been studied in women at average risk for breast cancer, but it is unknown whether these effects differ by breast cancer risk level. We used a vignette-based survey to evaluate how women across the spectrum of breast cancer risk perceive the experience of screening recall. METHODS: Women participating in mammography or breast MRI screening were recruited to complete a vignette-based survey. Using a numerical rating scale (0-100), women rated QOL for hypothetical scenarios of screening recall, both before and after benign results were known. Lifetime breast cancer risk was calculated using Gail and BRCAPRO risk models. Risk perception, trait anxiety, and breast cancer worry were assessed using validated instruments. RESULTS: The final study cohort included 162 women at low (n = 43, 26%), intermediate (n = 66, 41%), and high-risk (n = 53, 33%). Actual breast cancer risk was not a predictor of QOL for any of the presented scenarios. Across all risk levels, QOL ratings were significantly lower for the period during diagnostic uncertainty compared to after benign results were known (p < 0.05). In multivariable regression analyses, breast cancer worry was a significant predictor of decreased QoL for all screening scenarios while awaiting results, including scenarios with non-invasive imaging alone or with biopsy. High trait anxiety and family history predicted lower QOL scores after receipt of benign test results (p < 0.05). CONCLUSIONS: Women with high trait anxiety and family history may particularly benefit from discussions about the risk of recall when choosing a screening regimen.

Is Less More? A Microsimulation Model Comparing Cost-effectiveness of the Revised American Thyroid Association's 2015 to 2009 Guidelines for the Management of Patients With Thyroid Nodules and Differentiated Thyroid Cancer.

OBJECTIVE: To assess relative clinical and economic performance of the revised American Thyroid Association (ATA) thyroid cancer guidelines compared to current standard of care. BACKGROUND: Diagnosis of thyroid cancer in the United States has tripled whereas mortality has only marginally increased. Most patients present with small papillary carcinomas and have historically received at least a total thyroidectomy as a treatment. In 2015, the ATA released the revised guidelines recommending an option for active surveillance (AS) of small papillary thyroid carcinoma and thyroid lobectomy for larger unifocal tumors. METHODS: We created a Markov microsimulation model to evaluate the performance of the ATA's 2015 guidelines compared to the ATA's 2009 guidelines. We modeled a cohort of simulated patients with demographic and thyroid nodule characteristics representative of those presenting clinically in the United States. Outcome measures include life expectancy, quality-adjusted life years, costs, and frequency of surgical adverse events. RESULTS: In our base case analysis, the ATA 2015 strategy dominates the ATA 2009 strategy. The ATA 2015 strategy delivers greater discounted average quality-adjusted life years (13.09 vs 12.43) at a lower discounted average cost ($14,752 vs $20,126). Deaths due to thyroid cancer under the 2015 strategy are higher than the 2009 strategy but this is offset by a reduction in surgical deaths, leading to greater average life expectancy under the ATA 2015 strategy. The optimal strategy is sensitive to patients who experience a greater decrement in quality of life while undergoing AS. CONCLUSIONS: The ATA 2015 Guidelines represent a cost-effective strategy regarding AS and extent of surgery.

Long-term health outcomes and cost-effectiveness of coronary CT angiography in patients with suspicion for acute coronary syndrome.

BACKGROUND: Randomized trials have shown favorable clinical outcomes for coronary CT angiography (CTA) in patients with suspected acute coronary syndrome (ACS). Our goal was to estimate the cost-effectiveness of coronary CTA as compared to alternative management strategies for ACP patients over lifetime. METHODS: Markov microsimulation model was developed to compare cost-effectiveness of competitive strategies for ACP patients: 1) coronary CTA, 2) standard of care (SOC), 3) AHA/ACC Guidelines, and 4) expedited emergency department (ED) discharge protocol with outpatient testing. ROMICAT-II trial was used to populate the model with low to intermediate risk of ACS patient data, whereas diagnostic test-, treatment effect-, morbidity/mortality-, quality of life- and cost data were obtained from the literature. We predicted test utilization, costs, 1-, 3-, 10-year and over lifetime cardiovascular morbidity/mortality for each strategy. We determined quality adjusted life years (QALY) and incremental cost-effectiveness ratio. Observed outcomes in ROMICAT-II were used to validate the short-term model. RESULTS: Estimated short-term outcomes accurately reflected observed outcomes in ROMICAT-II as coronary CTA was associated with higher costs ($4,490 vs. $2,513-$4,144) and revascularization rates (5.2% vs. 2.6%-3.7%) compared to alternative strategies. Over lifetime, coronary CTA dominated SOC and ACC/AHA Guidelines and was cost-effective compared to expedited ED protocol ($49,428/QALY). This was driven by lower cardiovascular mortality (coronary CTA vs. expedited discharge: 3-year: 1.04% vs. 1.10-1.17; 10-year: 5.06% vs. 5.21-5.36%; respectively). CONCLUSION: Coronary CTA in patients with suspected ACS renders affordable long-term health benefits as compared to alternative strategies.

Repeat CT Performed Within One Month of CT Conducted in the Emergency Department for Abdominal Pain: A Secondary Analysis of Data From a Prospective Multicenter Study.

OBJECTIVE: The purpose of this study is to determine both the frequency of repeat CT performed within 1 month after a patient visits the emergency department (ED) and undergoes CT evaluation for abdominal pain and the frequency of worsened or new CT-based diagnoses. SUBJECTS AND METHODS: Secondary analysis was performed on data collected during a prospective multicenter study. The parent study included patients who underwent CT in the ED for abdominal pain between 2012 and 2014, and these patients constituted the study group of the present analysis. The proportion of patients who underwent (in any setting) repeat abdominal CT within 1 month of the index CT examination was calculated. For each of these patients, results of the index and repeat CT scans were compared by an independent panel and categorized as follows: no change (group 1); same process, improved (group 2); same process, worse (group 3); or different process (group 4). The proportion of patients in groups 1 and 2 versus groups 3 and 4 was calculated, and patient and ED physician characteristics were compared. RESULTS: The parent study included 544 patients (246 of whom were men [45%]; mean patient age, 49.4 years). Of those 544 patients, 53 (10%; 95% CI, 7.5-13%) underwent repeat abdominal CT. Patients' CT comparisons were categorized as follows: group 1 for 43% of patients (23/53), group 2 for 26% (14/53), group 3 for 15% (8/53), and group 4 for 15% (8/53). New or worse findings were present in 30% of patients (16/53) (95% CI, 19-44%). When patients with findings in groups 1 and 2 were compared to patients with findings in groups 3 and 4, no significant difference was noted in patient age (p = 0.25) or sex (p = 0.76), the number of days between scans (p = 0.98), and the diagnostic confidence of the ED physician after the index CT scan was obtained (p = 0.33). CONCLUSION: Short-term, repeat abdominal CT was performed for 10% of patients who underwent CT in the ED for abdominal pain, and it yielded new or worse findings for 30% of those patients.

A decision analysis comparing 3 active surveillance protocols for the treatment of patients with low-risk prostate cancer.

BACKGROUND: Active surveillance (AS) is a viable management option for approximately 50% of men who are newly diagnosed with prostate cancer. To the authors' knowledge, no direct comparisons between the different variants of AS protocols have been conducted to date. The authors developed a microsimulation decision model to evaluate which of 3 alternative AS protocols is optimal for men with low-risk prostate cancer, and compared each of these with immediate treatment. METHODS: Men who were diagnosed with low-risk prostate cancer at age 65 years were modeled as having been treated with either immediate therapy or via each of 3 AS protocols. Modeled AS protocols represent those in the literature; a modified AS protocol was included in a sensitivity analysis. Immediate therapy included radical prostatectomy, external-beam radiotherapy, or brachytherapy. Outcome measures were quality-adjusted life-years (QALYs) and costs. Cost-effectiveness analysis and deterministic and probabilistic sensitivity analyses were performed. RESULTS: Immediate therapy produced fewer QALYs than all variants of AS. Of the AS protocols evaluated, biennial biopsy was found to be the only efficient option, with an incremental cost-effectiveness ratio of $3490 per QALY compared with immediate therapy. It delayed the need for curative therapy by a mean of 56 months, and was found to be preferred in >86.9% of cases in probabilistic sensitivity analysis. A modified version of low-intensity AS dominated all other options. CONCLUSIONS: For a 65-year-old man with low-risk prostate cancer, AS with biennial biopsy appears to be highly cost-effective compared with common alternatives. An AS protocol using triennial biopsy was found to dominate all other strategies and should be considered for men who are comfortable with a longer period between biopsies. The optimal strategy depends on a patient's tolerance for periodic biopsies and comfort with delaying radical treatment. Physicians should incorporate these patient preferences into decision making.

Predictors of surveillance mammography outcomes in women with a personal history of breast cancer.

PURPOSE: To identify predictors of poor mammography surveillance outcomes based on clinico-pathologic features. METHODS: This study was HIPAA compliant and IRB approved. We performed an electronic medical record review for a cohort of women with American Joint Committee on Cancer (AJCC) Stage I or II invasive breast cancer treated with breast conservation therapy who developed subsequent in-breast treatment recurrence (IBTR) or contralateral breast cancer (CBC). Poor surveillance outcome was defined as second breast cancer not detected by surveillance mammography, including interval cancers (diagnosed within 365 days of surveillance mammogram with negative results) and clinically detected cancers (diagnosed without a surveillance mammogram in the preceding 365 days). Univariate and multivariate logistic regression were performed to identify predictors of poor mammography surveillance outcome, including patient and primary tumor characteristics, breast density, mode of primary tumor detection, and time to second cancer diagnosis. RESULTS: 164 women met inclusion criteria (65 with IBTR, 99 with CBC); 124 had screen-detected second cancers. On univariate analysis, poor surveillance outcome (n = 40) was associated with age at primary cancer diagnosis < 50 years (p < 0.0001), AJCC stage II primary cancers (p = 0.007), and heterogeneously or extremely dense breasts (p = 0.04). On multivariate analysis, age < 50 years at primary breast cancer diagnosis remained a significant predictor of poor surveillance outcome (p = 0.001). CONCLUSION: Women younger than age 50 at primary breast cancer diagnosis are at risk of poor surveillance mammography outcomes, and may be appropriate candidates for more intensive clinical and imaging surveillance.

The thyroid cancer policy model: A mathematical simulation model of papillary thyroid carcinoma in The U.S. population.

BACKGROUND: Thyroid cancer affects over ½ million people in the U.S. and the incidence of thyroid cancer has increased worldwide at a rate higher than any other cancer, while survival has remained largely unchanged. The aim of this research was to develop, calibrate and verify a mathematical disease model to simulate the natural history of papillary thyroid cancer, which will serve as a platform to assess the effectiveness of clinical and cancer control interventions. METHODS: Herein, we modeled the natural pre-clinical course of both benign and malignant thyroid nodules with biologically relevant health states from normal to detected nodule. Using established calibration techniques, optimal parameter sets for tumor growth characteristics, development rate, and detection rate were used to fit Surveillance Epidemiology and End Results (SEER) incidence data and other calibration targets. RESULTS: Model outputs compared to calibration targets demonstrating sufficient calibration fit and model validation are presented including primary targets of SEER incidence data and size distribution at detection of malignancy. Additionally, we show the predicted underlying benign and malignant prevalence of nodules in the population, the probability of detection based on size of nodule, and estimates of growth over time in both benign and malignant nodules. CONCLUSIONS: This comprehensive model provides a dynamic platform employable for future comparative effectiveness research. Future model analyses will test and assess various clinical management strategies to improve patient outcomes related to thyroid cancer and optimize resource utilization for patients with thyroid nodules.

Evaluating lung cancer screening in China: Implications for eligibility criteria design from a microsimulation modeling approach.

More than half of males in China are current smokers and evidence from western countries tells us that an unprecedented number of smoking-attributable deaths will occur as the Chinese population ages. We used the China Lung Cancer Policy Model (LCPM) to simulate effects of computed tomography (CT)-based lung cancer screening in China, comparing the impact of a screening guideline published in 2015 by a Chinese expert group to a version developed for the United States by the U.S. Centers for Medicare & Medicaid Services (CMS). The China LCPM, built using an existing lung cancer microsimulation model, can project population outcomes associated with interventions for smoking-related diseases. After calibrating the model to published Chinese smoking prevalence and lung cancer mortality rates, we simulated screening from 2016 to 2050 based on eligibility criteria from the CMS and Chinese guidelines, which differ by age to begin and end screening, pack-years smoked, and years since quitting. Outcomes included number of screens, mortality reduction, and life-years saved for each strategy. We projected that in the absence of screening, 14.98 million lung cancer deaths would occur between 2016 and 2050. Screening with the CMS guideline would prevent 0.72 million deaths and 5.8 million life-years lost, resulting in 6.58% and 1.97% mortality reduction in males and females, respectively. Screening with the Chinese guideline would prevent 0.74 million deaths and 6.6 million life-years lost, resulting in 6.30% and 2.79% mortality reduction in males and females, respectively. Through 2050, 1.43 billion screens would be required using the Chinese screening strategy, compared to 988 million screens using the CMS guideline. In conclusion, CT-based lung cancer screening implemented in 2016 and based on the Chinese screening guideline would prevent about 20,000 (2.9%) more lung cancer deaths through 2050, but would require about 445 million (44.7%) more screens than the CMS guideline.

Role of CT in the Diagnosis of Nonspecific Abdominal Pain: A Multicenter Analysis.

OBJECTIVE: The objective of our study was to determine whether specific patient and physician factors-known before CT-are associated with a diagnosis of nonspecific abdominal pain (NSAP) after CT in the emergency department (ED). MATERIALS AND METHODS: We analyzed data originally collected in a prospective multicenter study. In the parent study, we identified ED patients referred to CT for evaluation of abdominal pain. We surveyed their physicians before and after CT to identify changes in leading diagnoses, diagnostic confidence, and admission decisions. In the current study, we conducted a multiple regression analysis to identify whether the following were associated with a post-CT diagnosis of NSAP: patient age; patient sex; physicians' years of experience; physicians' pre-CT diagnostic confidence; and physicians' pre-CT admission decision if CT had not been available. We analyzed patients with and those without a pre-CT diagnosis of NSAP separately. For the sensitivity analysis, we excluded patients with different physicians before and after CT. RESULTS: In total, 544 patients were included: 10% (52/544) with a pre-CT diagnosis of NSAP and 90% (492/544) with a pre-CT diagnosis other than NSAP. The leading diagnoses changed after CT in a large proportion of patients with a pre-CT diagnosis of NSAP (38%, 20/52). In regression analysis, we found that physicians' pre-CT diagnostic confidence was inversely associated with a post-CT diagnosis of NSAP in patients with a pre-CT diagnosis other than NSAP (p = 0.0001). No other associations were significant in both primary and sensitivity analyses. CONCLUSION: With the exception of physicians' pre-CT diagnostic confidence, the factors evaluated were not associated with a post-CT diagnosis of NSAP.

Changes in Physician Decision Making after CT: A Prospective Multicenter Study in Primary Care Settings.

Purpose To determine the effect of computed tomography (CT) results on physician decision making in three common clinical scenarios in primary care. Materials and Methods This research was approved by the institutional review board (IRB) and was HIPAA compliant. All physicians consented to participate with an opt-in or opt-out mechanism; patient consent was waived with IRB approval. In this prospective multicenter observational study, outpatients referred by primary care providers (PCPs) for CT evaluation of abdominal pain, hematuria, or weight loss were identified. Prior to CT, PCPs were surveyed to elicit their leading diagnosis, confidence in that diagnosis (confidence range, 0%-100%), a rule-out diagnosis, and a management plan if CT were not available. Surveys were repeated after CT. Study measures were the proportion of patients in whom leading diagnoses and management changed (PCP management vs specialist referral vs emergency department transfer), median changes in diagnostic confidence, and the proportion of patients in whom CT addressed rule-out diagnoses. Regression analyses were used to identify associations between study measures and site and participant characteristics. Specifically, logistic regression analysis was used for binary study measures (change in leading diagnosis, change in management), and linear regression analysis was used for the continuous study measure (change in diagnostic confidence). Accrual began on September 5, 2012, and ended on June 28, 2014. Results In total, 91 PCPs completed pre- and post-CT surveys in 373 patients. In patients with abdominal pain, hematuria, or weight loss, leading diagnoses changed after CT in 53% (131 of 246), 49% (36 of 73), and 57% (27 of 47) of patients, respectively. Management changed in 35% (86 of 248), 27% (20 of 74), and 54% (26 of 48) of patients, respectively. Median absolute changes in diagnostic confidence were substantial and significant (+20%, +20%, and +19%, respectively; P ≤ .001 for all); median confidence after CT was high (90%, 88%, and 80%, respectively). PCPs reported CT was helpful in confirming or excluding rule-out diagnoses in 98% (184 of 187), 97% (59 of 61), and 97% (33 of 34) of patients, respectively. Significant associations between primary measures and site and participant characteristics were not identified. Conclusion Changes in PCP leading diagnoses and management after CT were common, and diagnostic confidence increased substantially. © RSNA, 2016 Online supplemental material is available for this article.

Radiologist Peer Review by Group Consensus.

PURPOSE: The objective of this study was to evaluate the feasibility of the consensus-oriented group review (COGR) method of radiologist peer review within a large subspecialty imaging department. METHODS: This study was institutional review board approved and HIPAA compliant. Radiologist interpretations of CT, MRI, and ultrasound examinations at a large academic radiology department were subject to peer review using the COGR method from October 2011 through September 2013. Discordance rates and sources of discordance were evaluated on the basis of modality and division, with group differences compared using a χ(2) test. Potential associations between peer review outcomes and the time after the initiation of peer review or the number of radiologists participating in peer review were tested by linear regression analysis and the t test, respectively. RESULTS: A total of 11,222 studies reported by 83 radiologists were peer reviewed using COGR during the two-year study period. The average radiologist participated in 112 peer review conferences and had 3.3% of his or her available CT, MRI and ultrasound studies peer reviewed. The rate of discordance was 2.7% (95% confidence interval [CI], 2.4%-3.0%), with significant differences in discordance rates on the basis of division and modality. Discordance rates were highest for MR (3.4%; 95% CI, 2.8%-4.1%), followed by ultrasound (2.7%; 95% CI, 2.0%-3.4%) and CT (2.4%; 95% CI, 2.0%-2.8%). Missed findings were the most common overall cause for discordance (43.8%; 95% CI, 38.2%-49.4%), followed by interpretive errors (23.5%; 95% CI, 18.8%-28.3%), dictation errors (19.0%; 95% CI, 14.6%-23.4%), and recommendation (10.8%; 95% CI, 7.3%-14.3%). Discordant cases, compared with concordant cases, were associated with a significantly greater number of radiologists participating in the peer review process (5.9 vs 4.7 participating radiologists, P < .001) and were significantly more likely to lead to an addendum (62.9% vs 2.7%, P < .0001). CONCLUSIONS: COGR permits departments to collect highly contextualized peer review data to better elucidate sources of error in diagnostic imaging reports, while reviewing a sufficient case volume to comply with external standards for ongoing performance review.