Knowledge of the likelihood that a screening-detected case of cancer has been overdiagnosed is vitally important to make treatment decisions and develop screening policy. An overdiagnosed case is an ...excess case detected by screening. Estimates of the frequency of overdiagnosis in breast and prostate cancer screening vary greatly across studies. This article identifies features of overdiagnosis studies that influence results and shows their effect by using published research. First, different ways to define and measure overdiagnosis are considered. Second, contextual features and how they affect overdiagnosis estimates are examined. Third, the effect of estimation approach is discussed. Many studies use excess incidence under screening as a proxy for overdiagnosis. Others use statistical models to make inferences about lead time or natural history and then derive the corresponding fraction of cases that are overdiagnosed. This article concludes with questions that readers of overdiagnosis studies can use to evaluate the validity and relevance of published estimates and recommends that authors of studies quantifying overdiagnosis provide information about these features.
The American Cancer Society (ACS) recommends that individuals with a cervix initiate cervical cancer screening at age 25 years and undergo primary human papillomavirus (HPV) testing every 5 years ...through age 65 years (preferred); if primary HPV testing is not available, then individuals aged 25 to 65 years should be screened with cotesting (HPV testing in combination with cytology) every 5 years or cytology alone every 3 years (acceptable) (strong recommendation). The ACS recommends that individuals aged >65 years who have no history of cervical intraepithelial neoplasia grade 2 or more severe disease within the past 25 years, and who have documented adequate negative prior screening in the prior 10 years, discontinue all cervical cancer screening (qualified recommendation). These new screening recommendations differ in 4 important respects compared with the 2012 recommendations: 1) The preferred screening strategy is primary HPV testing every 5 years, with cotesting and cytology alone acceptable where access to US Food and Drug Administration‐approved primary HPV testing is not yet available; 2) the recommended age to start screening is 25 years rather than 21 years; 3) primary HPV testing, as well as cotesting or cytology alone when primary testing is not available, is recommended starting at age 25 years rather than age 30 years; and 4) the guideline is transitional, ie, options for screening with cotesting or cytology alone are provided but should be phased out once full access to primary HPV testing for cervical cancer screening is available without barriers. Evidence related to other relevant issues was reviewed, and no changes were made to recommendations for screening intervals, age or criteria for screening cessation, screening based on vaccination status, or screening after hysterectomy. Follow‐up for individuals who screen positive for HPV and/or cytology should be in accordance with the 2019 American Society for Colposcopy and Cervical Pathology risk‐based management consensus guidelines for abnormal cervical cancer screening tests and cancer precursors.
Mammography screening can lead to overdiagnosis-that is, screen-detected breast cancer that would not have caused symptoms or signs in the remaining lifetime. There is no consensus about the ...frequency of breast cancer overdiagnosis.
To estimate the rate of breast cancer overdiagnosis in contemporary mammography practice accounting for the detection of nonprogressive cancer.
Bayesian inference of the natural history of breast cancer using individual screening and diagnosis records, allowing for nonprogressive preclinical cancer. Combination of fitted natural history model with life-table data to predict the rate of overdiagnosis among screen-detected cancer under biennial screening.
Breast Cancer Surveillance Consortium (BCSC) facilities.
Women aged 50 to 74 years at first mammography screen between 2000 and 2018.
Screening mammograms and screen-detected or interval breast cancer.
The cohort included 35 986 women, 82 677 mammograms, and 718 breast cancer diagnoses. Among all preclinical cancer cases, 4.5% (95% uncertainty interval UI, 0.1% to 14.8%) were estimated to be nonprogressive. In a program of biennial screening from age 50 to 74 years, 15.4% (UI, 9.4% to 26.5%) of screen-detected cancer cases were estimated to be overdiagnosed, with 6.1% (UI, 0.2% to 20.1%) due to detecting indolent preclinical cancer and 9.3% (UI, 5.5% to 13.5%) due to detecting progressive preclinical cancer in women who would have died of an unrelated cause before clinical diagnosis.
Exclusion of women with first mammography screen outside BCSC.
On the basis of an authoritative U.S. population data set, the analysis projected that among biennially screened women aged 50 to 74 years, about 1 in 7 cases of screen-detected cancer is overdiagnosed. This information clarifies the risk for breast cancer overdiagnosis in contemporary screening practice and should facilitate shared and informed decision making about mammography screening.
National Cancer Institute.
Purpose The guideline purpose is to provide the urologist with a framework for the early detection of prostate cancer in asymptomatic average risk men. Materials and Methods A systematic review was ...conducted and summarized evidence derived from over 300 studies that addressed the predefined outcomes of interest (prostate cancer incidence/mortality, quality of life, diagnostic accuracy and harms of testing). In addition to the quality of evidence, the panel considered values and preferences expressed in a clinical setting (patient-physician dyad) rather than having a public health perspective. Guideline statements were organized by age group in years (age <40; 40 to 54; 55 to 69; ≥70). Results Except prostate specific antigen-based prostate cancer screening, there was minimal evidence to assess the outcomes of interest for other tests. The quality of evidence for the benefits of screening was moderate, and evidence for harm was high for men age 55 to 69 years. For men outside this age range, evidence was lacking for benefit, but the harms of screening, including over diagnosis and overtreatment, remained. Modeled data suggested that a screening interval of two years or more may be preferred to reduce the harms of screening. Conclusions The Panel recommended shared decision-making for men age 55 to 69 years considering PSA-based screening, a target age group for whom benefits may outweigh harms. Outside this age range, PSA-based screening as a routine could not be recommended based on the available evidence. The entire guideline is available at www.AUAnet.org/education/guidelines/prostate-cancer-detection.cfm.
The vast majority of women diagnosed with ductal carcinoma in situ (DCIS) undergo treatment. Therefore, the risks of invasive progression and competing death in the absence of locoregional therapy ...are uncertain.
We performed survival analyses of patient-level data from DCIS patients who did not receive definitive surgery or radiation therapy as recorded in the US National Cancer Institute's Surveillance, Epidemiology, and End Results program (1992-2014). Kaplan-Meier curves were used to estimate the net risk of subsequent ipsilateral invasive cancer. The cumulative incidences of ipsilateral invasive cancer, contralateral breast cancer, and death were estimated using competing risk methods.
A total of 1286 DCIS patients who did not undergo locoregional therapy were identified. Median age at diagnosis was 60 years (inter-quartile range = 51-74 years), with median follow-up of 5.5 years (inter-quartile range = 2.3-10.6 years). Among patients with tumor grade I/II (n = 547), the 10-year net risk of ipsilateral invasive breast cancer was 12.2% (95% confidence interval CI = 8.6% to 17.1%) compared with 17.6% (95% CI = 12.1% to 25.2%) among patients with tumor grade III (n = 244) and 10.1% (95% CI = 7.4% to 13.8%) among patients with unknown grade (n = 495). Among all patients, the 10-year cumulative incidences of ipsilateral invasive cancer, contralateral breast cancer, and all-cause mortality were 10.5% (95% CI = 8.5% to 12.4%), 3.9% (95% CI = 2.6% to 5.2%), and 24.1% (95% CI = 21.2% to 26.9%), respectively.
Despite limited data, our findings suggest that DCIS patients without locoregional treatment have a limited risk of invasive progression. Although the cohort is not representative of the general population of patients diagnosed with DCIS, the findings suggest that there may be overtreatment, especially among older patients and patients with elevated comorbidities.
Background
US Black men are twice as likely to die from prostate cancer as men of other races. Lower quality care may contribute to this higher death rate.
Methods
Sociodemographic and clinical data ...were obtained for men in Surveillance, Epidemiology, and End Results‐Medicare diagnosed with clinically localized prostate cancer (cT1‐4N0/xM0/x) and managed primarily by radical prostatectomy (2005–2015). Surgical volume was determined for facility and surgeon. Relationships between race, surgeon and/or facility volume, and characteristics of treating facility with survival (all‐cause and cancer‐specific) were assessed using multivariable Cox regression and competing risk analysis.
Results
Black men represented 6.7% (n = 2123) of 31,478 cohort. They were younger at diagnosis, had longer time from diagnosis to surgery, lower socioeconomic status, higher prostate‐specific antigen (PSA), and higher comorbid status compared with men of other races (p < .001). They were less likely to receive care from a surgeon or facility in the top volume percentile (p < .001); less likely to receive surgical care at a National Cancer Institute‐designated cancer center and more likely seen at a minority‐serving hospital; and less likely to travel ≥50 miles for surgical care. On multivariable analysis stratified by surgical volume, Black men receiving care from a surgeon or facility with lower volumes demonstrated increased risk of prostate cancer mortality (hazard ratio, 1.61; 95% confidence interval, 1.01–2.69) adjusting for age, clinical stage, PSA, and comorbidity index.
Conclusions
Black Medicare beneficiaries with prostate cancer more commonly receive care from surgeons and facilities with lower volumes, likely affecting surgical quality and outcomes. Access to high‐quality prostate cancer care may reduce racial inequities in disease outcomes, even among insured men.
Plain language summary
Black men are twice as likely to die of prostate cancer than other US men.
Lower quality care may contribute to higher rates of prostate cancer death.
We used surgical volume to evaluate the relationship between race and quality of care.
Black Medicare beneficiaries with prostate cancer more commonly received care from surgeons and facilities with lower volumes, correlating with a higher risk of prostate cancer death and indicating scarce resources for care.
Access to high‐quality prostate cancer care eases disparities in disease outcomes.
Patient‐centered interventions that increase access to high‐quality care for Black men with prostate cancer are needed.
Lack of access to high quality care for Black men with prostate cancer may contribute to their substantially higher rate of death when compared with men of other races in the United States. Surgical volume—a surrogate for quality—and race are assessed in localized prostate cancer care.
Clinical trials test the efficacy of a treatment in a select patient population. We examined whether cancer clinical trial patients were similar to nontrial, "real-world" patients with respect to ...presenting characteristics and survival.
We reviewed the SWOG national clinical trials consortium database to identify candidate trials. Demographic factors, stage, and overall survival for patients in the standard arms were compared with nontrial control subjects selected from the Surveillance, Epidemiology, and End Results program. Multivariable survival analyses using Cox regression were conducted. The survival functions from aggregate data across all studies were compared separately by prognosis (≥50% vs <50% average 2-year survival). All statistical tests were two-sided.
We analyzed 21 SWOG studies (11 good prognosis and 10 poor prognosis) comprising 5190 patients enrolled from 1987 to 2007. Trial patients were younger than nontrial patients (P < .001). In multivariable analysis, trial participation was not associated with improved overall survival for all 11 good-prognosis studies but was associated with better survival for nine of 10 poor-prognosis studies (P < .001). The impact of trial participation on overall survival endured for only 1 year.
Trial participation was associated with better survival in the first year after diagnosis, likely because of eligibility criteria that excluded higher comorbidity patients from trials. Similar survival patterns between trial and nontrial patients after the first year suggest that trial standard arm outcomes are generalizable over the long term and may improve confidence that trial treatment effects will translate to the real-world setting. Reducing eligibility criteria would improve access to clinical trials.
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