False-positive Screening Results Research Articles

#357 Sex differences in the aldosterone-renin system must be taken into account during screening for primary aldosteronism

Abstract Background and Aims Primary aldosteronism (PA) is one of the most frequent causes of secondary hypertension. Patients with PA are at higher risk for cardiovascular and renal complications than those with essential hypertension. Screening for PA is rarely considered in the assessment of a hypertensive patient, in part because of difficulties in the diagnostic process. Nevertheless, identification of PA is crucial to guide patients towards optimal management, either by mineralocorticoid receptor blockade or by unilateral adrenalectomy, with the latter offering potential cure for patients with aldosterone-producing adenomas (APAs). Numerous studies show inadequate diagnostic accuracy of the aldosterone:renin ratio (ARR) for screening for PA, particularly in females, who have higher ARR variability and lower renin compared to males. Women have a higher risk of false-positive screening results leading to unnecessary confirmatory tests. Use of oral contraception (OC) or hormone replacement therapy (HRT) may also confound the ARR. The aim of this study was to develop improved screening tools for PA, including adjustments for sex-specific differences. Method PROSALDO is a multicenter prospective cohort study designed to test new diagnostic procedures for patients with suspected PA. Medication that interfere with the renin-angiotensin-aldosterone system are withdrawn before laboratory measurements. For screening, the routine ARR is calculated along with additional probability scores based on a peripheral venous steroid hormone profile (PVSP). The latter allows for identification of potentially false-negative ARR results. After a positive screening result of the ARR and/or a high probability score based on the PVSP, PA is confirmed or excluded with a saline infusion test (SIT). PA confirmation is followed by adrenal venous sampling (AVS) to identify patients with unilateral PA. We compared aldosterone, renin and ARR levels between females and males with and without PA. Renin- and sex dependent formulas for aldosterone screening cut-offs were derived from the study population. Logistic regression and the corresponding receiver operating characteristic (ROC) curves were used to determine and compare diagnostic accuracies. Results PA was confirmed in 159 (24.5%) of 649 (328 (50.5%) females and 321 (49.5%) males). Lateralization was shown in 58 out of 117 patients who underwent AVS. In hypertensive patients without PA, ARR was higher in females vs. males (26.4 vs. 11.7 pmol/mU, P < 0.0001), mainly due to a lower renin (9.2 vs. 16.2 mU/L, P < 0.0001). Furthermore, ARRs in patients with vs. without PA showed more overlap in females compared to males. Areas under ROC curves (AUROCs) for the ARR were 0.857 (CI 95%: 0.797-0.902) vs. 0.912 (CI 95%: 0.876-0.938) for females and males respectively. Using liquid chromatography mass spectrometry measurements (LC-MS/MS) of aldosterone, an ARR cut-off of 21.75 pmol/L yielded a sensitivity of 93% with only 45% specificity in females, while for males, a specificity of 66% was obtained for a sensitivity of 97.7%. This meant for females having a higher risk of false-positive screening results (OR 2.36 (CI 95%: 1.65-3.41)), even after excluding patients on OC or HRT (OR 2.17 (CI 95%: 1.5-3.17)). We derived a renin- and sex-dependent formula for the calculation of aldosterone cut-offs, which improved diagnostic accuracy for both males and females (ΔAUROC = 0.05 and 0.045, P < 0.0001 and 0.02 respectively): for a diagnostic sensitivity of 94-95%, specificity was improved to 61% in females and 82% in males. Conclusion Lower renin in females without PA leads to higher ARRs and thus a higher risk of false-positive screening results. Higher overlap of the ARR between females with and without PA compared to their male counterparts weakens utility of the ARR for discrimination of patients with and without PA. Sex- and renin-specific aldosterone cut-offs for screening for PA offer improved diagnostic accuracy. Diagnostic accuracy remains however superior in males, which highlights the need for further optimization of diagnostic procedures specifically in women.

The impact of confined placental mosaicism on prenatal cell-free DNA screening: Insights from a monocentric study of 99 cases

IntroductionConfined placental mosaicism (CPM) is thought to be one of the main sources of false-positive prenatal cell-free DNA (cfDNA) screening results, but extensive and systematic studies to prove this statement are limited. We evaluate the contribution of CPM to false-positive prenatal cfDNA screening results in the largest cohort published to date. MethodWe systematically offered postnatal analysis on placenta and umbilical cord to women who had a negative amniocentesis following a positive prenatal cfDNA screening result. A standardized protocol was used in which (when available) biopsies were taken at five locations in the placenta and umbilical cord. ResultsWe analyzed a series of 99 placentas. CPM could be confirmed in 32.3 % of cases (32/99). CPM was detected across all subtypes of chromosomal aberrations (common and rare autosomal trisomies, sex chromosome abnormalities, copy number variations and autosomal monosomies). A lower detection rate was present in umbilical cord biopsies in comparison with placental biopsies. When comparing different sections of the placenta, no clear difference could be observed with regard to the probability of CPM being present nor to the grade of mosaicism. DiscussionWe confirm an important role for CPM in explaining false-positive prenatal cfDNA screening results. Placental regional differences are common. Given its limited clinical relevance, we do however not advocate placental studies in a diagnostic setting.

Performance of an Artificial Intelligence System for Breast Cancer Detection on Screening Mammograms from BreastScreen Norway.

Purpose To explore the stand-alone breast cancer detection performance, at different risk score thresholds, of a commercially available artificial intelligence (AI) system. Materials and Methods This retrospective study included information from 661 695 digital mammographic examinations performed among 242 629 female individuals screened as a part of BreastScreen Norway, 2004-2018. The study sample included 3807 screen-detected cancers and 1110 interval breast cancers. A continuous examination-level risk score by the AI system was used to measure performance as the area under the receiver operating characteristic curve (AUC) with 95% CIs and cancer detection at different AI risk score thresholds. Results The AUC of the AI system was 0.93 (95% CI: 0.92, 0.93) for screen-detected cancers and interval breast cancers combined and 0.97 (95% CI: 0.97, 0.97) for screen-detected cancers. In a setting where 10% of the examinations with the highest AI risk scores were defined as positive and 90% with the lowest scores as negative, 92.0% (3502 of 3807) of the screen-detected cancers and 44.6% (495 of 1110) of the interval breast cancers were identified with AI. In this scenario, 68.5% (10 987 of 16 040) of false-positive screening results (negative recall assessment) were considered negative by AI. When 50% was used as the cutoff, 99.3% (3781 of 3807) of the screen-detected cancers and 85.2% (946 of 1110) of the interval breast cancers were identified as positive by AI, whereas 17.0% (2725 of 16 040) of the false-positive results were considered negative. Conclusion The AI system showed high performance in detecting breast cancers within 2 years of screening mammography and a potential for use to triage low-risk mammograms to reduce radiologist workload. Keywords: Mammography, Breast, Screening, Convolutional Neural Network (CNN), Deep Learning Algorithms Supplemental material is available for this article. © RSNA, 2024 See also commentary by Bahl and Do in this issue.

Understand the FDA-cleared fentanyl testing: A clinical evaluation of the SEFRIA fentanyl immunoassay

BackgroundScreening for fentanyl has been adopted by many clinical laboratories to detect illicit drug use and monitor medication adherence. However, compared to other urine drug testing, fentanyl screening assays are relatively new and therefore their clinical performances are largely unknown. This study extensively evaluated the clinical performance, positive cutoff, and interference profile of SEFRIA fentanyl immunoassay in real patient settings. MethodsThe FDA-cleared cutoff of 1.0 was verified with 21 urine samples with low or undetectable levels of fentanyl. After assay implementation, all screened-positive samples were confirmed by liquid chromatography-tandem mass spectrometry. A new cutoff was derived from the numeric values of the false positive (FP) screening results. The FP rates before and after implementing the new cutoff were compared. Interferences were identified by an untargeted drug analysis and confirmed by spiking experiments. ResultsA total of 3951 screening results were reviewed in the first two months of the assay utilization, 410 were screened-positive, and 157 (38 %) were FP. After a new cutoff of 1.3 was implemented, the FP rate was reduced to 17 % based on 11119 screening results. Trazodone, labetalol, and haloperidol were identified as major interferents, accounting for 56 % of the FP results using the cutoff of 1.3. ConclusionBy applying the new cutoff and including an interference comment to positive screening results, the FP rate was reduced from initial 38 % to 7.5 % (17 % times 56 %).

False-positive MDA findings in HRMS-based screening of putrefied postmortem blood samples-Identification of the interference as N-acetyltyramine.

An unidentified compound in putrefied postmortem blood samples showed identical accurate mass and chromatographic behavior as 3,4-methylenedioxyamphetamine (MDA) and led to false-positive preliminary screening results. The aim of the study was to identify this unknown interference. Postmortem blood samples were analyzed after protein precipitation on a QExactive Focus high-resolution mass spectrometer (Thermo Fisher, Germany) coupled to a RP C18 column (Macherey-Nagel, Germany). Based on the analysis of mass spectrometry (MS) adducts and isotope ratios using fullscan (m/z 134-330) information, the empiric formula of the protonated molecule [M + H]+ of the unknown compound was found to be C10H14O2N (+ 0.6 ppm). Product ion spectra recorded using normalized collision energy 22% showed a base peak of C8H9O1 (+ 1.5 ppm) and a low-abundant water loss to C7H9 (+ 1.9 ppm), neutral losses of C2H2O and NH3 were found. Based on fullscan and MS-MS information and under consideration of the observed order of neutral losses, the compound was presumptively identified as N-acetyltyramine. This assumption was supported by SIRIUS software showing a SIRIUS score of 99.43% for N-acetyltyramine. Finally, the putative structure annotation was confirmed by a reference compound. The described false-positive MDA findings could be attributed to the presence of N-acetyltyramine in putrefied blood samples. Being an isomer of MDA, N-acetyltyramine could not be distinguished by high-resolution data of the protonated molecules. The presented results once again highlight that false-positive findings may occur even in hyphenatedhigh-resolution mass spectrometry (HRMS) when using full-scan information only.

Integrating artificial intelligence into lung cancer screening: a randomised controlled trial protocol

IntroductionLung cancer (LC) is the most common cause of cancer-related deaths worldwide. Its early detection can be achieved with a CT scan. Two large randomised trials proved the efficacy of...

Health State Utilities Associated with False-Positive Cancer Screening Results.

Early cancer detection can significantly improve patient outcomes and reduce mortality rates. Novel cancer screening approaches, including multi-cancer early detection tests, have been developed. Cost-utility analyses will be needed to examine their value, and these models require health state utilities. The purpose of this study was to estimate the disutility (i.e., decrease in health state utility) associated with false-positive cancer screening results. In composite time trade-off interviews using a 1-year time horizon, UK general population participants valued 10 health state vignettes describing cancer screening with true-negative or false-positive results. Each false-positive vignette described a common diagnostic pathway following a false-positive result suggesting lung, colorectal, breast, or pancreatic cancer. Every pathway ended with a negative result (no cancer detected). The disutility of each false positive was calculated as the difference between the true-negative and each false-positive health state, and because of the 1-year time horizon, each disutility can be interpreted as a quality-adjusted life-year decrement associated with each type of false-positive experience. A total of 203 participants completed interviews (49.8% male; mean age = 42.0 years). The mean (SD) utility for the health state describing a true-negative result was 0.958 (0.065). Utilities for false-positive health states ranged from 0.847 (0.145) to 0.932 (0.059). Disutilities for false positives ranged from -0.031 to -0.111 (-0.041 to -0.111 for lung cancer; -0.079 for colorectal cancer; -0.031 to -0.067 for breast cancer; -0.048 to -0.088 for pancreatic cancer). All false-positive results were associated with a disutility. Greater disutility was associated with more invasive follow-up diagnostic procedures, longer duration of uncertainty regarding the eventual diagnosis, and perceived severity of the suspected cancer type. Utility values estimated in this study would be useful for economic modeling examining the value of cancer screening procedures.

A Monovalent Fab Affinity-Capture and Elution Bridging Immunoassay Overcomes Rheumatoid Factor Interference while Accurately Detecting Antidrug Antibodies.

Rheumatoid factor (RF) consists of autoantibodies that bind the fragment crystallizable (Fc) region of human immunoglobulin G (IgG) and present in sera of rheumatoid arthritis (RA) patients. Immunoassays to detect antidrug antibodies (ADA) in RA patient samples may experience interference due to RF binding and crosslinking Fc regions of the capture and detection antibody reagents. To overcome this interference, a novel Fab affinity-capture and elution (ACE)-bridging immunoassay (Fab ACE-Bridge) was developed with monovalent-recombinant Fab to avoid RF interference. ACE and ACE-Bridge assays were developed to detect ADA against a therapeutic monoclonal antibody using samples from healthy donors, psoriasis patients, and RA patients. The performance of these assays was compared to a novel Fab ACE-Bridge assay, in which monoclonal antibody was replaced with monovalent Fab. High screening signals in the ACE and ACE-Bridge assays were detected in RA patient samples but not in samples from healthy donors or psoriasis patients. The high screening signals in RA samples did not inhibit to the expected extent in the confirmatory assay, a consistent feature of false-positive screening results. Further investigation revealed RF as the interferent affecting assay performance. Modification of the ACE-Bridge assay by using monovalent Fab eliminated RF interference while allowing for sensitive and drug-tolerant detection of authentic ADA. RF interfered significantly in traditional ACE and ACE-Bridge assays. Implementation of a novel monovalent Fab ACE-Bridge assay overcame RF interference. The use of monovalent Fab is recommended for immunogenicity assays when assessing ADA in RA patient samples.

False-Positive Human Immunodeficiency Virus Screening Results in Pregnancy During the Coronavirus Disease 2019 (COVID-19) Pandemic.

False-positive human immunodeficiency virus (HIV) test results are rare but have been documented in the setting of certain underlying conditions such as Epstein-Barr virus, metastatic cancer, and certain autoimmune conditions. A retrospective cohort study in a large hospital system was conducted to compare the occurrence of false-positive HIV fourth-generation test results before and after the coronavirus disease 2019 (COVID-19) pandemic in a population of pregnant patients (N=44,187; 22,073 pre-COVID and 22,114 during COVID). The COVID cohort had a significantly higher frequency of false-positive HIV test results compared with the pre-COVID cohort (0.381 vs 0.676, P =.002). Within the COVID cohort, 25% of patients had a positive polymerase chain reaction test result for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) preceding their false-positive HIV test results. When this subgroup was excluded, the difference in frequency of false-positive HIV test results between the cohorts was no longer significant (0.381 vs 0.507, P =.348). Our findings suggest that SARS-CoV-2 seropositivity was associated with an increased frequency of false-positive HIV test results in the pregnant population.

Effect of the large waves of COVID-19 on false-positive results in annual lung cancer screening.

e18596 Background: Chest X ray (CXR) has been the most common screen test procedure for detection of lung cancer. We have shown that repeat visitors (R) had a significantly lower proportion of CXR abnormalities requiring medication than the first-time visitors (F) at annual lung cancer screening. (Kimura T. Health Prim Car, 2021). In 2022, Japan experienced three large waves of COVID-19 mainly the Omicron variants (the 6th: Jan-Mar, the 7th: Jul-Sep and the 8th: Oct to present). The later the wave, the larger the scale. The Omicron variant spreads more easily than the original or the Delta variants up to the 5th waves. The hypothesis was that these COVID waves may have influenced lung cancer screening. Methods: Our clinic “MedCity21” is a university outpatient clinic for a complete medical check-up as part of a private health screening program. Of course, we check temperature, respiratory symptoms, and any history of COVID infection and vaccination of the participants (pts). Our facility allows COVID-infected pts to have medical check-ups four weeks after they are cured. The pts with abnormalities detected on CXR were notified by telephone request and invited to our specialty clinic for chest CT scan as further examination. Each year from 2018 to 2022, we examined the varieties of abnormal shadows on CXR and CT scans and compared the differences between 2022 and each year before to 2022 using the chi-squared tests. Results: In 2022, there were 14522 pts of which F and R were 27.1% and 72.9% respectively. The percentage of pts with a history of COVID was 1.68% in January, but gradually increased, reaching a plateau of 20% in October. There were 231pts (1.6%) with CXR abnormalities requiring further investigation. The rates in F and R were 1.3% and 1.7%, respectively. A total of 132 pts (56.7%) of 63 pts in F and 69 pts in R underwent chest CT scans at our facility after the call for recommendation for further investigation. The distribution of CXR and CT variations was consistent with our previous report. There was one confirmed case of lung cancer among F, and 2 among R in 2022. It should be noted that the CT confirmation revealed that there were 10 pts with nodular shadow on CXR, of whom 5 were found to have COVID infection after 1 month follow-up. Conclusions: There was a significant decrease in the number of first-time visitors in 2022 compared to previous years (p < 0.001). The percentage of cases returning to our clinic for CT for further investigation has decreased dramatically (p < 0.001). These were attributed to the large COVID waves. Notably, for the first time in the last 5 years, the detection rates of CXR abnormalities were reversed for R and F. In some cases, nodule shadows were difficult to determine whether they were lung cancer or COVID. The number of people with previous COVID-19 infection will continue to increase. The COVID pandemic and subsequent behavioral changes have affected the way people manage their health status.

Choice of Assessment and Subsequent Risk of Breast Cancer among Women with False-Positive Mammography Screening

Women with false-positive mammography screening results have a two- to four-fold higher risk of breast cancer. This study aimed to investigate if the subsequent risk of breast cancer after a false-positive mammography screening is associated with the received diagnostic assessment. The study population consisted of women who underwent false-positive mammography screening from January 2010 to June 2019. They were categorised into seven groups depending on the elements in the assessment (standard care: additional mammography, ultrasound, and if they had a relevant biopsy). Risks of interval cancer, next-round screen-detected cancer, and long-term breast cancer for non-standard care assessments were compared to standard care assessments using Binomial and Cox regression models. We included 44,279 women with a false-positive result. Invasive assessments that lacked an ultrasound or additional mammography were not more associated with an increased risk of subsequent cancers compared to that of 'all three elements'. The few assessments that included 'only ultrasound' or 'only mammography' resulted in higher relative risks of next-round screen-detected cancer of 1.52 (95% CI: 0.93-2.47) and 1.67 (95% CI: 0.54-5.16), respectively, compared to that of standard care. The increased subsequent risk of breast cancer among women with a previous false-positive result was not found to be correlated with the choice of elements in the assessment process.

Machine learning to improve false-positive results in the Dutch newborn screening for congenital hypothyroidism

ObjectiveThe Dutch Congenital hypothyroidism (CH) Newborn Screening (NBS) algorithm for thyroidal and central congenital hypothyroidism (CH-T and CH-C, respectively) is primarily based on determination of thyroxine (T4) concentrations in dried blood spots, followed by thyroid-stimulating hormone (TSH) and thyroxine-binding globulin (TBG) measurements enabling detection of both CH-T and CH-C, with a positive predictive value (PPV) of 21%. A calculated T4/TBG ratio serves as an indirect measure for free T4. The aim of this study is to investigate whether machine learning techniques can help to improve the PPV of the algorithm without missing the positive cases that should have been detected with the current algorithm. Design & methodsNBS data and parameters of CH patients and false-positive referrals in the period 2007–2017 and of a healthy reference population were included in the study. A random forest model was trained and tested using a stratified split and improved using synthetic minority oversampling technique (SMOTE). NBS data of 4668 newborns were included, containing 458 CH-T and 82 CH-C patients, 2332 false-positive referrals and 1670 healthy newborns. ResultsVariables determining identification of CH were (in order of importance) TSH, T4/TBG ratio, gestational age, TBG, T4 and age at NBS sampling. In a Receiver-Operating Characteristic (ROC) analysis on the test set, current sensitivity could be maintained, while increasing the PPV to 26%. ConclusionsMachine learning techniques have the potential to improve the PPV of the Dutch CH NBS. However, improved detection of currently missed cases is only possible with new, better predictors of especially CH-C and a better registration and inclusion of these cases in future models.

Analysis of Risk Factors and Screening Results of Neonatal Congenital Hypothyroidism in a Tertiary Care Center of Southern China.

To explore the risk factors for neonatal congenital hypothyroidism (CH) and the influencing factors of false-positive results in CH screening. In this study, 255 neonatal patients with CH who completed the screening and further diagnosis and 366 neonates with positive CH screening results and normal thyroid function were selected as the case group. 246 healthy neonates with normal thyroid function were selected as the control group. Gestational age, birth-weight, maternal age, small for gestational age (SGA), perinatal factors (gestational thyroid dysfunction, gestational diabetes mellitus, etc.) were used as influencing factors, using χ 2 tests were performed for comparison. The statistically significant variables were analyzed with Logistic multiple regression models, and the difference was considered statistically significant (P<0.05). There were statistical differences in the SGA, maternal gestational diabetes mellitus, thyroid disease, and the proportion using assisted reproduction technology among the case group, false-positive screening group, and control group (χ 2 was 11.943, 6.857, 6.999, 9.732, respectively, P < 0.05). The results of multivariate logistic regression analysis showed that the gestational thyroid disease (OR = 8.452, 95% CI:1.051-67.982), gestational diabetes mellitus (OR = 2.654, 95% CI:1.051-6.706), and assisted reproduction (OR = 0.194, 95% CI:0.041-0.911) were the influencing factors for neonatal CH, and the difference was statistically significant (P < 0.05). The SGA (OR = 2.556, 95% CI:1.027-6.361), gestational thyroid disease (OR = 7.801, 95% CI:1.03-59.057), gestational diabetes mellitus (OR = 2.731, 95% CI:1.18-6.322), and assisted reproduction (OR = 0.28, 95% CI:0.102-0.765) were the influencing factors of the false-positive screening results of neonatal CH. The difference was statistically significant (P < 0.05). Neonatal CH and positive screening results are influenced by assisted reproduction, gestational thyroid dysfunction, gestational diabetes mellitus, and SGA.

Relationship between False Positive Screening Results of Down Syndrome and Adverse Pregnancy Outcomes.

Maternal serum sample screening in the first and second trimesters has been commonly used to identify women who are at risk of fetal trisomy 21. In addition, these serum markers are associated with adverse perinatal outcomes. Hence, the present study was conducted to determine the relationship between false positive screening results of Down syndrome and adverse pregnancy outcomes. This prospective, two-group, cohort study was conducted on 608 pregnant women who had undergone fetal contingent screening. They were selected through convenience sampling in the twentieth week of pregnancy and were followed up until delivery. The raw Odd Ratios (OR), Relative Risk (RR), and adjusted OR of adverse pregnancy outcomes were calculated in the false positive and true negative groups. The adjusted OR of developing preeclampsia was 1.98 (95%CI: 1.14-3.42), and its RR was 2.13 (95%CI: 1.34-3.38) times higher in the false positive group. Moreover, the adjusted OR of Small for Gestational Age (SGA) was 2.80 (95%CI: 1.76-4.47), and its RR was 2.28 (95%CI: 1.54-3.36) times higher in the false positive group. The adjusted OR of Low Birth Weight (LBW) was 3.34 (95%CI: 1.97-5.64), and its RR was 2.65 (95%CI: 1.72-4.11) times higher in the false positive group. In addition, no significant difference was observed between false positive and true negative groups in terms of preterm birth. Women with a false positive fetal screening test result are more likely to suffer from preeclampsia, SGA, and LBW and require planned prenatal care.

Effect of Oral Contraception on Screening Tests for Primary Aldosteronism: A 10-Year Longitudinal Study.

Primary aldosteronism (PA) and oral contraception (OC) can both cause hypertension in young women. However, the effect of OC on the screening test for PA, the aldosterone to renin ratio (ARR), is not clear. We evaluated the impact of OC on the screening test for PA. In this retrospective cohort study, we analyzed data from the female offspring (Gen2) of women enrolled in the Raine Study, a population-based birth cohort, who had blood pressure (BP) measurements, blood samples, and information about OC use at age 17 years (N = 484) and/or age 27 years (N = 486). Aldosterone concentration was significantly higher in OC users than nonusers at 17 years (median 486 pmol/L vs 347 pmol/L, P < 0.001). Renin concentration was significantly lower in OC users at both 17 years (13.4 mU/L vs 20.6 mU/L) and 27 years (9.2 mU/L vs 11.8 mU/L), hence the ARR was significantly higher in OC users compared to nonusers at both 17 years (31.5 vs 18.3) and 27 years (27.3 vs 21.1). The proportion of participants with ARR > 70 pmol/mU (current threshold for PA detection) was significantly higher in OC users at both 17 years (12.6% vs 2.1%) and 27 years (6.4% vs 0.4%); however, they had comparable BP to those with ARR < 70. OC use at any age abolished the relationship between ARR and BP that is observed in nonusers. OC can increase the ARR and cause a false positive PA screening result. Until more reliable criteria for PA screening in OC users are established, alternative contraception should be considered during screening.

Risk of false-positive result in mammography screening in Brazil

False-positive results on mammography screening are common, putting a burden on both women and the health care system. This study aimed to estimate the risk of false-positive results in Brazilian mammography screening based on data from the Brazilian Unified National Health System (SUS) information systems. A retrospective cohort study was conducted with women aged 40-69 years, who underwent mammography screening and breast histopathological examination at SUS from 2017 to 2019. The rate of false-positive results was estimated based on the prevalence of altered BI-RADS results on mammography screening and the proportion of benign results on breast histopathological examination. Of the 10,671 women with histopathological examination at SUS, 46.2% had a benign result, and this proportion was significantly higher in women aged 40-49 years compared to women aged 50-69 years. The estimate of false-positive results was 8.18 cases per 100 women aged 40-49 years and 6.06 per 100 women aged 50-69 years. This information is useful for public managers in evaluating mammography screening programs, as well as for health care providers to guide women on the implications of mammography screening.

Evaluation of specificity and sensitivity of IRT/IRT protocol in the cystic fibrosis newborn screening program: 6-year experience of three tertiary centers.

We aimed to evaluate cutoff values of immunoreactive trypsinogen (IRT)/IRT and determine relationship between IRT values and clinical characteristics of children with cystic fibrosis (CF). This study is cross-sectional study. Data of children with positive newborn screening (NBS) between 2015 and 2021 were evaluated in three pediatric pulmonology centers. Age at admission, sex, gestational age, presence of history of meconium ileus, parental consanguinity, sibling with CF, and doll-like face appearance, first and second IRT values, sweat chloride test, fecal elastase, fecal fat, biochemistry results, and age at CF diagnosis were recorded. Sensitivity and specificity of IRT cutoff values were evaluated. Of 815 children with positive NBS, 58 (7.1%) children were diagnosed with CF. Median values of first and second IRT were 157.2 (103.7-247.6) and 113.0 (84.0-201.5) μg/L. IRT values used in current protocol, sensitivity was determined as 96.6%, specificity as 17.2% for first IRT, and 96.6% sensitivity, 20.5% specificity for second IRT. Positive predictive value (PPV) was determined as 7.1%. When cutoff value for first IRT was estimated as 116.7μg/L, sensitivity was 69.0% and specificity was 69.6%, and when cutoff value was set to 88.7μg/L for second IRT, sensitivity was 69.0% and specificity was 69.0%. Area under curve was 0.757 for first and 0.763 for second IRT (p < 0.001, p < 0.001, respectively). PPV was calculated as 4.3%. Conclusion: Although sensitivity of CF NBS is high in our country, its PPV is significantly lower than expected from CF NBS programs. False-positive NBS results could have been overcome by revising NBS strategy. What is Known: • Although immunoreactive trypsinogen elevation is a sensitive test used in cystic fibrosis newborn screening, its specificity is low. • In countries although different algorithms are used, all strategies begin with the measurement of immunoreactive trypsinogen in dried blood spots. What is New: • In our study, it was shown that use of the IRT/IRT protocol for cystic fibrosis newborn screening is not sufficient for the cut-off values determined by the high number of patients. • Newborn screening strategy should be reviewed to reduce false positive newborn screening results.

High-risk HPV testing vs liquid-based cytology for cervical cancer screening among 25- to 30-year-old women: A historical cohort study.

High-risk human papilloma virus (hrHPV) DNA testing is more sensitive than cytology screening, achieving greater protection against cervical cancer. Controversy exists regarding the preferred screening method for women 25-30 years of age. At this age, infection with HPV is common and usually transient. Consequently, hrHPV screening in this age group is fraught with high false-positive screening results, leading to more colposcopies and unnecessary treatments with the potential for harm. In the present study, we aimed to compare the results of two screening methods in relation to high-grade cervical intraepithelial lesion detection rate in the young age group of 25-30 years. Retrospective information on cervical cytology, hrHPV testing, colposcopy referrals and histologic results, from one screening round, were retrieved from the Maccabi HealthCare Health Maintenance Organization centralized database during the study period from March 1, 2017 to April 1, 2019 for 25- to 30-year-old women. Screening with hrHPV testing for types 16, 18 and 12 other hrHPV types was compared with the conventional PAP liquid-based cytology (LBC) test. Odds ratio (OR) of detection with 95% confidence interval (CI) was calculated for cervical intraepithelial neoplasia (CIN) grade 3 or higher (CIN 3+). During the study period, 42 244 women 25-30 years old underwent cervical cancer screening; of them, 20 997 were screened with LBC between March 1, 2017 and March 1, 2018 and compared with 21 247 who were screened with hrHPV between April 1, 2018 and April 1, 2019. Testing for hrHPV resulted in a higher colposcopy referral rate compared with primary LBC screening: 9.8% vs 7.8%, respectively; (OR 1.28; 95% CI 1.2-1.37; p< 0.001). Screening with hrHPV led to significantly higher detection of CIN 3+ lesions (OR 1.4; 95% CI 1.2-1.6; p< 0.001) compared with LBC. HPV infections with non-16/18 hrHPV (other hrHPV) were the most prevalent (84.8%). In women 25-30 years old, primary hrHPV screening was associated with a higher detection rate of CIN 3+ compared with cytology screening and should be considered for primary screening in this age group.

False-Positive Amphetamines in Urine Drug Screens: A 6-Year Review.

Immunoassays are routinely used to provide rapid urine drug screening results in the clinical setting. These screening tests are prone to false-positive results and ideally require confirmation by mass spectrometry. In this study, we have examined a large number of urine specimens where drugs other than amphetamines may have caused a false-positive amphetamine immunoassay screening result. Urine drug screens (12,250) in a clinical laboratory that used the CEDIA amphetamine/ecstasy method were reviewed for false-positive results over a 6-year period (2015-2020). An additional 3,486 referred samples, for which confirmatory--mass spectrometry was requested, were also reviewed. About 86 in-house samples and 175 referral samples that were CEDIA false-positive screens were further analyzed by an LC-QTOF general unknown screen. Potential cross-reacting drugs were identified, and their molecular similarities to the CEDIA targets were determined. Commercial standards were also analyzed for cross-reactivity in the amphetamine/ecstasy CEDIA screen. Positive amphetamine results in 3.9% of in-house samples and 9.9% of referred tests for confirmatory analysis were false positive for amphetamines. Of these false-positive specimens, on average, 6.8 drugs were detected by the LC-QTOF screen. Several drugs were identified as possible cross-reacting drugs to the CEDIA amphetamine/ecstasy assay. Maximum common substructure scores for 70 potential cross-reacting compounds were calculated. This was not helpful in identifying cross-reacting drugs. False-positive amphetamine screens make up to 3.9-9.9% of positive amphetamine screens in the clinical laboratory. Knowledge of cross-reacting drugs may be helpful when mass spectrometry testing is unavailable.

Costs and Effects of Implementing Digital Tomosynthesis in a Population-Based Breast Cancer Screening Program: Predictions Using Results from the To-Be Trial in Norway.

BackgroundAlthough several studies from Europe and the US have shown promising screening results favoring digital breast tomosynthesis compared with standard digital mammography (DM), both costs and effects of implementing tomosynthesis in routine screening programs remain uncertain. The cost effectiveness of using tomosynthesis in routine screening is debated in the literature, and model inputs from randomized trials are lacking. Using parameters mainly from a randomized controlled trial (the To-Be trial), we simulated costs and effects of implementing tomosynthesis in the national screening program BreastScreen Norway.MethodsThe To-Be trial was performed in Bergen from 2016 to 2017 within BreastScreen Norway, where females were randomized to either digital breast tomosynthesis including synthetic mammograms (DBT) or DM. The trial was followed by a cohort study offering all females DBT in 2018–2019. The trial included over 37,000 females, and allowed for estimation of short-term costs and effects related to screening, recall examinations and cancer detection. Using these and recent Norwegian estimates for 10-year stage-specific survival and treatment costs, the cost effectiveness of replacing DM with DBT in BreastScreen Norway was simulated in a decision tree model with probabilistic sensitivity analyses. Outcomes included false-positive screening results, screen-detected and interval cancers, stage at diagnosis, all-cause deaths, life-years gained, costs at recall and treatment and incremental cost-effectiveness ratio.ResultsThe estimated additional cost of DBT was €8.10. Simulating ten rounds of screening from 2018 and 10-year survival and costs, 500 deaths were averted and 2300 life-years gained at an additional screening cost of €29 million for females screened with DBT versus DM. Taking over-diagnosis, recall and treatment costs into account, DBT was dominant in the deterministic analysis. The incremental cost-effectiveness ratio indicated cost savings of €1400 per life-year gained. Probabilistic sensitivity analyses showed that DBT was cost effective in over 50% of the simulations at all willingness-to-pay levels per life-year gained, and in 80% of the simulations at levels above €22,000. If willingness-to-pay levels up to €35,000 were assumed, DBT would be cost effective in over 50% of the simulations for additional costs of DBT of up to €32, almost four times the estimated additional cost of €8.10.ConclusionDBT may be cost effective if implemented in BreastScreen Norway. However, generalizability of results could depend on factors varying between countries, such as recall rates, program sensitivity and specificity, treatment cost and willingness-to-pay levels.Supplementary InformationThe online version contains supplementary material available at 10.1007/s41669-022-00343-5.