Improving Antibiotic Use for Ventilator-Associated Pneumonia Through Diagnostic Stewardship: A Proof-of-Concept Mixed Methods Study.

Background: Overtreatment of ventilator-associated pneumonia (VAP) in the intensive care unit is driven by positive respiratory tract cultures in the absence of a clinical picture of pneumonia. We evaluated the potential for diagnostic stewardship at the respiratory culture reporting step. Methods: In this mixed methods study, we conducted a baseline evaluation of lower respiratory tract (LRT) culture appropriateness and antibiotic prescribing, followed by a nonrandomized intervention in 2 adult intensive care units. The intervention was a comment in the report to indicate potential colonization instead of organism identification when LRT cultures were inappropriate-that is, not meeting criteria for pneumonia as adjudicated by a physician using a standard algorithm. Results: At baseline, among 66 inappropriate LRT cultures, antibiotic treatment for VAP was more frequent with identification of potential pathogens in the index culture when compared with no growth/normal flora (16/35 [46%] vs 7/31 [23%], P = .049). In the intervention period, 28 inappropriate cultures with growth of potential pathogens underwent report modification. The proportion of episodes for which antibiotic therapy for VAP was completed was significantly lower in the intervention group vs the baseline group (5/28 [18%] vs 16/35 [46%], P = .02). Conclusions: Diagnostic stewardship for VAP could be facilitated by modification of LRT culture reporting guided by clinical features of pneumonia.

Time Trends, Regional Variation and Associations of Low-Allergy Formula Prescribing in England.

BACKGROUND: Cow's milk allergy (CMA) overdiagnosis appears to be increasing and is associated with excessive low-allergy formula prescription. We evaluated recent trends and regional variation in low-allergy formula prescribing for CMA in England, and assessed potential risk factors for higher prescribing rates. METHODS: Data on national and regional prescribing of low-allergy formulas were extracted from England's electronic prescription database using R. Region-level factors were evaluated for potential associations with regional low-allergy formula prescription rates using multivariate linear regression. Analysis of national prescribing trends covered 2007-2023, analysis of regional variation and region-level factors examined 2017-2019, prior to a re-organisation of the regional healthcare structure in England. RESULTS: Low-allergy formula prescribing increased from 6.1 to 23.3 L per birth nationally, between 2007 and 2023. Regional prescribing rate varied from 0.8 to 47.6 L per birth in 2017-2019. We found significant associations between regional low-allergy formula prescribing rate and regional prescribing rates for milk feed thickeners Gaviscon Infant and Carobel Instant (ß = 0.10, p < 0.01), and for other anti-reflux medications used in young children (ß = 0.89 p < 0.01). Inconsistent associations were seen with prescribing junior adrenaline auto-injectors and oral antibiotics. A model including these four variables accounted for 37% of regional variation in low-allergy formula prescribing rate. Region-level socio-economic deprivation, CMA guideline recommendations and paediatric allergy service provision were not associated with low-allergy formula prescribing. CONCLUSIONS: Low-allergy formula prescribing in England is increasing, varies significantly by region and is consistently associated with prescribing rates for milk feed thickeners and other anti-reflux medication for young children. Community prescribing behaviours may be important determinants of CMA overdiagnosis.

Deceptive Measures of "Success" in Early Cancer Detection.

Early detection of cancer is considered a cornerstone of preventive medicine and is widely perceived as the gateway to reducing cancer deaths. Based on this assumption, large trials are currently underway to evaluate the accuracy of early detection tests. It is imperative, therefore, to set meaningful "success criteria" in early detection that reflect true improvements in health outcomes. This article discusses the pitfalls of measuring the success of early detection tests for cancer, particularly in the context of screening programs, and provides illustrative examples that demonstrate how commonly used metrics can be deceptive. Early detection can result in downstaging (favourable stage shift) when more early-stage cancers are diagnosed, even without reducing late-stage disease, potentially leading to overdiagnosis and overtreatment. Survival statistics, primarily cancer-specific survival, can be misleading due to lead time, where early detection simply extends the known duration of the disease without prolonging actual lifespan or improving overall survival. Additionally, the misuse of relative measures, such as proportions, ratios, and percentages, often make it impossible to ascertain the true benefit of a procedure and can distort the impact of screening as they are influenced by diagnostic practices, misleadingly improving perceived mortality reductions. Understanding these biases is crucial for accurately assessing the effectiveness of cancer detection methods and ensuring appropriate patient care.

Estimating the Proportion of Overdiagnosis among Prostate, Breast, and Thyroid Cancers in China: Findings from the Global Burden of Disease 2019.

The incidence of prostate, breast, and thyroid cancers has increased in China over the past few decades. Whether and how much these increases can be attributed to overdiagnosis are less understood. This study aimed to estimate the proportion of overdiagnosis among these three cancers in China during 2004-2019. The age-specific cancer incidence, cancer mortality, and all-cause mortality in China were extracted from the Global Burden of Diseases 2019. The lifetime risk of developing and that of dying from each cancer were calculated using the life table method. The proportion of overdiagnosis of a cancer was estimated as the difference between the lifetime risk of developing the cancer and that of suffering from the cancer (including death, metastasis, and symptoms caused by the cancer), further divided by the lifetime risk of developing the cancer. The highest possible values of these parameters were adopted in the estimation so as to obtain the lower bounds of the proportions of overdiagnosis. Sensitivity analyses assuming different lag periods between the diagnosis of a cancer and death from the cancer were performed. The results showed that the lifetime risk of developing prostate, breast, and thyroid cancer increased dramatically from 2004 to 2019 in China, while the increase in the lifetime risk of dying from these cancers was less pronounced. The proportions of overdiagnosis among prostate, breast, and thyroid cancers were estimated to be 7.88%, 18.99%, and 24.92%, respectively, in 2004, and increased to 18.20%, 26.25%, and 29.24%, respectively, in 2019. The increasing trends were statistically significant for all three cancers (all p < 0.001). In sensitivity analyses, the proportions of overdiagnosis decreased, but upward trends over time remained for all three cancers. In conclusion, the overdiagnosis of prostate, breast, and thyroid cancers in China increased from 2004 to 2019, with the highest proportion seen in thyroid cancer and the most rapid increase seen in prostate cancer. Multifaceted efforts by policy makers, guideline developers, and clinicians are needed to tackle this problem.

X-ray imaging of multiple adjacent regions in paediatric patients: Potential utility for diagnosis and patient management.

BACKGROUND: In emergency presentations, it is not uncommon for patients to present with imaging requests of multiple body regions to detect concurrent injury. While current literature explores diagnostic efficacy of adjacent imaging for forearm fractures, there is limited research on its effectiveness across all extremities. This paper explores the diagnostic yield of X-ray adjacent imaging of the upper and lower limb in paediatric patients. METHODS: A retrospective audit was performed using information available on radiology request forms from paediatric patients (age <18 years) that had multiple X-rays of adjacent body regions over six months at two hospitals. The main or first X-ray was referred to as initial imaging, while all subsequent X-rays of adjacent regions was considered secondary imaging. Clinical history and radiologists' findings were collected, categorised, and analysed using Chi square. RESULTS: There were 661 X-rays performed across 277 patients. Initial imaging was significantly more likely to detect injuries or abnormalities (35 %) than X-rays of adjacent regions (1.6 %), with 94 % of all abnormalities detected on initial imaging overall (χ2(3) = 241.247, p < 0.001). X-ray request forms with no clinical symptoms were significantly more likely to have no findings detected (χ2(3) = 53.493, p < 0.001). CONCLUSION: X-ray imaging of a body region adjacent to an injury has low diagnostic yield, suggesting the need for interventions to reduce unnecessary adjacent X-ray imaging. Clinical history information was often limited and concurrent injuries were low.

Utility of common investigations for suspected inflammatory arthritis in adults.

Inflammatory arthritis may be the principal feature or one component of an inflammatory rheumatological disease. It is a clinical diagnosis, principally made based on the patient's history and examination. Specific investigations, such as rheumatoid factor and human leucocyte antigen B27 gene, may support the diagnosis in the context of a suggestive clinical presentation, but a diagnosis cannot be made based on these tests alone because positive results may also be seen in healthy individuals. To reduce the likelihood of false positive results, laboratory and radiological investigations should be tailored to the suspected diagnosis based on pretest probability. While musculoskeletal symptoms are a common presentation in general practice, specific features that increase suspicion of an inflammatory arthritis include prolonged morning stiffness (more than 1 hour) that is improved by exercise or movement. A broad 'rheumatological panel' increases the likelihood of false positive results and should be avoided to prevent unnecessary further investigations and treatment, and unwarranted anxiety in both the patient and the doctor.

Melanoma in situ and low risk pT1a melanoma: Need for new diagnostic terminology.

Melanoma incidence has risen rapidly, at least until recently, while mortality has changed only a little, a phenomenon suggestive of overdiagnosis, which can be defined as the diagnosis as "melanoma" of a lesion that would not have had the competence to cause death or symptoms even if it had not been excised. Overdiagnosis has been attributed to efforts at early diagnosis ("overdetection"), and to changes in criteria resulting in diagnosis as melanoma of lesions previously termed nevi ("overdefinition"). In terms of overdefinition, there is evidence that criteria for the histopathologic diagnosis of melanoma has changed over a period of approximately two decades. Specialization may play a role in overdefinition; research has shown that when pathologists interpret the same lesion, dermatopathologists are more likely to diagnose low stage (AJCC T1a) melanomas and general/surgical pathologists are more likely to diagnose atypical nevi. An important subset that contributes to overdiagnosis is those melanomas that lack the property of tumorigenic vertical growth phase, thus lacking metastatic competence, and perhaps not warranting diagnosis as overt melanomas. Studies have defined subsets of patients with very low stage lesions diagnosed as melanomas in which observed survival has been 100%. In the past, many of these lesions would have been diagnosed as nevi, constituting overdefinition. Other key characteristics for very low risk (or no risk) lesions that are currently termed invasive "melanomas" include low Breslow thickness, Clark's level II invasion, absence of mitoses, and clinically, lack of observed or experienced dynamic changes. We propose a provisional terminology for diagnosing extremely low risk subgroups as "Melanocytic neoplasms of low malignant potential", aimed at reducing the negative personal and social effects of a cancer diagnosis for patients whose health and wellbeing are in reality not affected by an overdiagnosed "melanoma". With additional confirmation and appropriate consensus, it is likely that some of these subgroups can be reclassified as atypical or dysplastic nevi.

Case report: Possible role of low-dose PEM for avoiding unneeded procedures associated with false-positive or equivocal breast MRI results.

Contrast-enhanced breast magnetic resonance imaging (MRI) is currently recommended as a screening tool for high-risk women and has been advocated for women with radiologically dense breast tissue. While breast MRI is acknowledged for its high sensitivity (with an exception for lower-grade ductal carcinoma in situ (DCIS) where emerging techniques like diffusion-weighted imaging offer improvement), its limitations include sensitivity to hormonal changes and a relatively high false-positive rate, potentially leading to overdiagnosis, increased imaging uncertainty, and unnecessary biopsies. These factors can exacerbate patient anxiety and impose additional costs. Molecular imaging with breast-targeted Positron Emission Tomography (PET) has shown the capability to detect malignancy independent of breast density and hormonal changes. Furthermore, breast-targeted PET has shown higher specificity when compared with MRI. However, traditional PET technology is associated with high radiation dose, which can limit its widespread use particularly in repeated studies or for undiagnosed patients. In this case report, we present a clinical application of low-dose breast imaging utilizing a breast-targeted PET camera (Radialis PET imager, Radialis Inc). The case involves a 33-year-old female patient who had multiple enhanced lesions detected on breast MRI after surgical removal of a malignant phyllodes tumor from the right breast. A benign core biopsy was obtained from the largest lesion seen in the left breast. One month after the MRI, 18F-fluorodeoxyglucose (18F-FDG) PET imaging session was performed using the Radialis PET Imager. Although the Radialis PET Imager has proven high count sensitivity and the capability to detect breast lesions with low metabolic activity (at a dose similar to mammography), no areas of increased 18F-FDG uptake were visualized in this particular case. The patient underwent a right-sided nipple-sparing mastectomy and left-sided lumpectomy, with bilateral reconstruction. The excised left breast tissue was completely benign, as suggested by both core biopsy and the PET results. The case presented highlights a promising clinical application of low-dose breast-targeted PET imaging to mitigate the uncertainty associated with MRI while keeping radiation doses within the safe range typically used in X-ray mammography.

Screening Low-Risk Individuals for Lung Cancer: The Need May Be Present, but the Evidence of Benefit Is Not.

Worldwide, lung cancer is the most common killer among cancers, advanced disease has worse outcomes, earlier stage detection leads to better outcomes, and high-quality screening has a favorable net benefit. With the mortality reduction recognized from annual low-radiation dose computed tomography by screening those at high risk, there has been consideration that this benefit could translate to those who have never smoked. There have been several large-scale, single-arm, observational trials in Asia in persons with light to no smoking histories, with or without a family history of lung cancer, which have revealed high or higher lung cancer detection rates than previously reported in high-risk persons who currently or formerly smoked. The Early Detection Program for Lung Cancer in Taiwan, of nearly 50,000 persons, revealed that the cancer detection rate for those screened with low-radiation dose computed tomography was more than twofold higher in light- or never-smokers with a family history of lung cancer compared with high-risk persons with more than 30 or more pack-years exposure and meeting U.S. Preventative Services Task Force criteria for screening. In addition, more than 90% of the cancers detected in those with a family history were in early stage. On the basis of those findings, the researchers concluded that screening first-degree relatives of those with a family history of lung cancer, irrespective of smoking history, would lead to a decrease in lung cancer mortality. We believe that the findings in this cohort and others like it represent substantial overdiagnosis and that the harms associated with screening a population that has a low likelihood of developing lethal cancers have not been thoroughly considered. Here, we provide our perspective and consider the potential benefits and harms of screening populations outside those currently eligible using the U.S. Preventative Services Task Force criteria.

Applying current European periodontitis clinical practice guidelines is not feasible even for the richest countries in the world.

Clinical practice guidelines aim to enhance the quality, equality and consistency of care but often demand more time than is available, rendering adherence impractical and exceeding feasible resources. The 2017 introduction of a new periodontal classification system by the American Academy of Periodontology (AAP) and the European Federation of Periodontology (EFP) sought to refine clinical and epidemiological practices by serving as the basis for clinical practice guidelines and epidemiological investigations around the world. Following this classification, the EFP recommends supportive periodontal care visits every 3-12 months for all periodontitis cases. Given that in Norway, approximately 72% of the adult population are identified as periodontitis cases under the current AAP/EFP case definition, this poses a significant demand on healthcare resources. We calculated that between 60% and 70% of all estimated available working hours available for adult dental care provided by dentists and dental hygienists in Norway in 2017 would be spent on supportive periodontal care visits alone if the recommendations were to be met. This situation calls for a reevaluation of disease definitions and clinical practice guidelines to ensure they are practical, financially feasible and patient-outcome relevant.

Outcomes of Resected Lung Cancer Diagnosed Through Screening and Incidental Pulmonary Nodule Programs in a Mississippi Delta Cohort.

Introduction: Early lung cancer detection programs improve surgical resection rates and survival but may skew toward more indolent cancers. Methods: Hypothesizing that differences in stage-stratified survival indicate differences in biological aggressiveness and possible length-time and overdiagnosis bias, we assessed a cohort who had curative-intent resection, categorized by diagnostic pathways: screening, incidental pulmonary nodule program, and non-program based. Survival was analyzed using Kaplan-Meier plots, log-rank tests, and Cox regression, comparing aggregate and stage-stratified survival across cohorts with Tukey's method for multiple testing. Results: Of 1588 patients, 111 patients (7%), 357 patients (22.5%), and 1120 patients (70.5%) were diagnosed through screening, pulmonary nodule, and non-program-based pathways; 0% versus 9% versus 6% were older than 80 years (p = 0.0048); 17%, 23%, and 24% had a Charlson Comorbidity score greater than or equal to 2 (p = 0.0143); 7%, 6%, and 9% had lepidic adenocarcinoma; 26%, 31%, and 34% had poorly or undifferentiated tumors (p = 0.1544); and 93%, 87%, and 77% had clinical stage I (p < 0.0001).Aggregate 5-year survival was 87%, 72%, and 65% (p = 0.0009), including 95%, 74%, and 74% for pathologic stage I. Adjusted pairwise comparisons showed similar survival in screening and nodule program cohorts (p = 0.9905). Nevertheless, differences were significant between screening and non-program-based cohorts (p = 0.0007, adjusted hazard ratio 0.33 [95% confidence interval: 0.18-0.6]) and between nodule and nonprogram cohorts (adjusted hazard ratio 0.77 [95% confidence interval: 0.61-0.99]). Stage I comparisons yielded p = 0.2256, 0.1131, and 0.911. In respective pathways, 0%, 2%, and 2% of patients with stage I disease who were older than 80 years had a Charlson score greater than or equal to 2 (p = 0.3849). Conclusions: Neither length-time nor overdiagnosis bias was evident in NSCLC diagnosed through screening or incidental pulmonary nodule programs.

Malaria Diagnosis at the Pediatric Emergency Unit of a Teaching Hospital in Makurdi, North Central Nigeria.

Background: Globally, there were 241 million cases of malaria in 2020, with an estimated 627,000 deaths with Nigeria accounting for 27% of the global malaria cases. In sub-Saharan Africa, testing is low with only 28% of children with a fever receiving medical advice or a rapid diagnostic test in 2021. In Nigeria, there are documented reports of over-diagnosis and over-treatment of malaria in children. Therefore, this study examined the diagnosis of malaria at the Benue State University Teaching Hospital, Makurdi. Methods: A 5-year (2018-2022) retrospective study was carried out at the Emergency Pediatric Unit (EPU). Records of all children presenting to the EPU with an assessment of malaria were retrieved and reviewed. Data was analyzed using SPSS 23. Results: Out of 206 children reviewed, 128 (62.1%) were tested using either malaria RDT or microscopy while 78(37.9%) were not tested. Out of the number tested, 59(46.1%) were negative while 69(53.9%) tested positive, of which 14(20.3%) had uncomplicated malaria while 55(79.7%) had severe malaria. However, while 97.1% (n=67) of the positive cases were treated with IV artesunate, 69.5% (n=41) of those who tested negative and 88.5% (69) of those who were not tested also received IV artesunate. Moreover, while 85.5% (n=59) of those who tested positive received oral artemisinin-based combination therapy (ACT), 72.9% (n=43) of those who tested negative and 67.9% (53) of those who were not tested also received oral ACT. Conclusion: There was over-diagnosis of malaria, and subsequently, over-treatment. Hence continued emphasis on parasitological confirmation of malaria before treatment is recommended.

Thyroid Cancer in Regions Most Contaminated after the Chernobyl Disaster.

Exposure to ionizing radiation, especially during childhood, is a well-established risk factor for thyroid cancer. Following the 1986 Chernobyl nuclear power plant accident the total number of cases of thyroid cancer registered between 1991 and 2015 in males and females who were less than 18 years old exceeded 19,000 (in Belarus and Ukraine, and in the most contaminated oblasts of the Russian Federation). However, as indicated by the United Nations Scientific Committee on the Effects of Atomic Radiation the fraction of the incidence of thyroid cancer attributable to radiation exposure among the non-evacuated residents of the contaminated regions of Belarus, Ukraine and Russia is of the order of 0.25. Apparently, the increased registration of thyroid neoplasms in the parts of these countries is a classical 'screening effect', i.e., massive diagnostic examinations of the risk-aware populations performed with modern eqipment resulting in detection of many occult neoplasms (incidentalomas). Moreover, one type of thyroid cancer previously called 'encapsulated follicular variant of papillary thyroid carcinoma' is non-invasive and instead of 'carcinoma' should now be recognized as 'noninvasive follicular thyroid neoplasm with papillary-like nuclear features.' Other potential causes of overdiagnosing of thyroid tumors include increase of the spontaneous incidence rate of this disease with age, iodine deficiency among children from Belarus, Russia and Ukraine, and/or consumption by these children of drinking water containing high levels of nitrates that likely coincides with the carcinogenic effect of radiation on the thyroid gland.

Incidence and mortality trends of primary cutaneous melanoma: A 50-year Rochester Epidemiologic Project study.

Background: National cancer reporting-based registry data, although robust, lacks granularity for incidence trends. Expert opinion remains conflicted regarding the possibility of melanoma overdiagnosis in the context of rising incidence without a corresponding rise in mortality. Objective: To characterize 10- and 50-year trends in melanoma incidence and mortality. Methods: Multicenter, population-based epidemiologic study utilizing the Rochester Epidemiology Project for Olmsted County, Minnesota residents diagnosed with melanoma from 01/01/1970 to 12/21/2020. Age- and sex-adjusted incidence and disease-specific mortality are calculated. Results: Two thousand three hundred ten primary cutaneous melanomas were identified. Current age- and sex-adjusted incidence rates increased 11.1-fold since 1970s (P < .001). Over the last decade, there is an overall 1.21-fold (P < .002) increase, with a 1.36-fold increase (P < .002) among females and no significant increase among males (1.09-fold increase, P < .329). Melanoma-specific mortality decreased from 26.7% in 1970s to 1.5% in 2010s, with a hazard ratio (HR) reduction of 0.73 (P < .001) per 5-year period. Increased mortality was associated with Breslow thickness (HR 1.35, P < .001), age at diagnosis (HR 1.13, P = .001) left anatomic site (HR 1.98, P = .016), and nodular histogenic subtype (HR 3.08, P < .001). Limitations: Retrospective nature and focused geographic investigation. Conclusion: Melanoma incidence has continued to increase over the past decade, most significantly in females aged 40+. Trend variations among age and sex cohorts suggests external factors beyond overdiagnosis may be responsible. Disease-specific mortality of melanoma continues to decrease over the last 50 years.

Secular Increasing Trends in Female Thyroid Cancer Incidence in Taiwan.

BACKGROUND: Thyroid cancer incidence has increased globally in recent decades, especially in females, although its trends in Taiwan have not been studied extensively. This study aimed to investigate changes in female incidence and possible causes of thyroid cancer in Taiwan. METHODS: Using the Taiwan Cancer Registry (TCR) Database, age-standardized incidence rates, age-specific incidence rates and birth cohorts were calculated. Correlation between female thyroid cancer incidence and cohort fertility rates were examined. RESULTS: Thyroid cancer incidence increased in Taiwanese female, with age-adjusted rates per 100,000 people increasing from 7.37 during 1995-1999 to 20.53 during 2015-2019; the annual percentage change (APC) was 5.9% (95% CI, 5.3-6.5). Age-specific incidence rates increased with age, with peak rates occurring at younger ages. The APCs in the 50-54 age group were the highest (6.8%, 95% CI, 6.1-7.5). Incidence rates also increased with later birth cohorts. We observed a significant negative correlation between thyroid cancer incidence and fertility rates in the same birth cohort. CONCLUSIONS: We hypothesize that overdiagnosis may be a main reason for the rapidly increasing thyroid cancer incidence in Taiwanese females. Notably, we observed a strong negative correlation between fertility and thyroid cancer incidence. However, our study is limited by the absence of individual-level cancer data in the TCR database. These associations with fertility will be an important subject for future thyroid cancer research.

Pulmonary adenocarcinoma of low malignant potential defines indolent NSCLC associated with overdiagnosis in the national lung screening trial.

BACKGROUND: The national lung screening trial (NLST) demonstrated a reduction in lung cancer mortality with lowdose CT (LDCT) compared to chest x-ray (CXR) screening. Overdiagnosis was high (79%) among bronchoalveolar carcinoma (BAC) currently replaced by adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA) and adenocarcinoma of low malignant potential (LMP) exhibiting 100% disease specific survival (DSS). OBJECTIVE: Compare the outcomes and proportions of BAC, AIS, MIA, and LMP among NLST screendetected stage IA NSCLC with overdiagnosis rate. METHODS: Whole slide images were reviewed by a thoracic pathologist from 174 of 409 NLST screen-detected stage IA LUAD. Overdiagnosis rates were calculated from follow-up cancer incidence rates. RESULTS: Most BAC were reclassified as AIS/MIA/LMP (20/35 = 57%). The 7-year DSS was 100% for AIS/MIA/LMP and 94% for BAC. Excluding AIS/MIA/LMP, BAC behaved similarly to NSCLC (7-year DSS: 86% vs. 83%, p= 0.85) The overdiagnosis rate of LDCT stage IA NSCLC was 16.6% at 11.3-years, matching the proportion of AIS/MIA/LMP (16.2%) but not AIS/MIA (3.5%) or BAC (22.8%). CONCLUSIONS: AIS/MIA/LMP proportionally matches the overdiagnosis rate among stage IA NSCLC in the NLST, exhibiting 100% 7-year DSS. Biomarkers designed to recognize AIS/MIA/LMP preoperatively, would be useful to prevent overtreatment of indolent screen-detected cancers.

Impact of annual trend volume of low-dose computed tomography for lung cancer screening on overdiagnosis, overmanagement, and gender disparities.

BACKGROUND: With the increasing prevalence of nonsmoking-related lung cancer in Asia, Asian countries have increasingly adopted low-dose computed tomography (LDCT) for lung cancer screening, particularly in private screening programs. This study examined how annual LDCT volume affects lung cancer stage distribution, overdiagnosis, and gender disparities using a hospital-based lung cancer database. METHODS: This study analyzed the annual utilized LDCT volume, clinical characteristics of lung cancer, stage shift distribution, and potential overdiagnosis. At the individual level, this study also investigated the relationship between stage 0 lung cancer (potential strict definition regarding overdiagnosis) and the clinical characteristics of lung cancer. RESULTS: This study reviewed the annual trend of 4971 confirmed lung cancer cases from 2008 to 2021 and conducted a link analysis with an LDCT imaging examination database over these years. As the volume of lung cancer screenings has increased over the years, the number and proportion of stage 0 lung cancers have increased proportionally. Our study revealed that the incidence of stage 0 lung cancer increased with increasing LDCT scan volume, particularly during the peak growth period from 2017 to 2020. Conversely, stage 4 lung cancer cases remained consistent across different time intervals. Furthermore, the increase in the lung cancer screening volume had a more pronounced effect on the increase in stage 0 lung cancer cases among females than it had among males. The estimated potential for overdiagnosis brought about by the screening process, compared to non-participating individuals, ranged from an odds ratio of 7.617 to one of 17.114. Both strict and lenient definitions of overdiagnosis (evaluating cases of stage 0 lung cancer and stages 0 to 1 lung cancer) were employed. CONCLUSIONS: These results provide population-level evidence of potential lung cancer overdiagnosis in the Taiwanese population due to the growing use of LDCT screening, particularly concerning the strict definition of stage 0 lung cancer. The impact was greater in the female population than in the male population, especially among females younger than 40 years. To improve lung cancer screening in Asian populations, creating risk-based prediction models for smokers and nonsmokers, along with gender-specific strategies, is vital for ensuring survival benefits and minimizing overdiagnosis.