Fundamentals of Receiver Operating Characteristic Curve Analyses
Albert Vexler, Alan D. Hutson, Xiwei Chen in Statistical Testing Strategies in the Health Sciences, 2017
Thompson (2003) considered the assessment of the overall diagnostic accuracy of a sequence of tests (e.g., repeated screening tests). The complexity of diagnostic choices with two or more continuous tests was illustrated, and different approaches to reducing the dimensionality were presented and evaluated. For instance, in practice, when a single test is used repeatedly in routine screening, the same screening threshold is typically used at each screening visit. One possible alternative is to adjust the threshold at successive visits according to individual-specific characteristics. Such possibilities represent a particular slice of a ROC surface, corresponding to all possible combinations of test thresholds. The author focused on the development and examples of the setting where an overall test is defined to be positive if any of the individual tests are believed to be positive. The ideas developed were illustrated by an example of application to screening for prostate cancer using prostate-specific antigen.
Cancer screening
Mark R Baker in Modernising Cancer Services, 2018
Prostate cancer fulfils some of the criteria required of a disease that might be managed by population screening. In men aged 50-60 years, rectal examination and prostate-specific antigen testing will detect clinically suspicious areas within the prostate. However, it is not known which of the prostate cancers, which are known to be present in 30-40% of men aged over 60 years, will be detected. Only a small proportion of cancers that are known to be present become clinically evident, and more men die with prostate cancer than because of it. There is also uncertainty as to how effective aggressive local treatments are in altering the natural history of the disease. It is unclear whether screening would be followed by a reduction in morbidity and mortality. A screening effect has been observed in the USA, with an increase in incidence and a decrease in the proportion of men with metastases.15 The National Screening Committee is developing a prostate cancer risk management programme to offer further advice to people who are anxious about the disease. The most urgent evidence that is required concerning prostate screening is evidence of the effectiveness of different treatment strategies.
Genitourinary, adrenal and breast
Dave Maudgil, Anthony Watkinson in The Essential Guide to the New FRCR Part 2A and Radiology Boards, 2017
Are the following statements regarding prostate adeno-carcinoma true or false? Approximately 20% of patients with prostate cancer have a normal prostate specific antigen (PSA) level.For stage T2c tumour must be present in both lobes.Stage T3a tumour extends into seminal vesicles.Tumours are usually hyperechoic on transrectal ultra-sonography.MRI is highly sensitive for extracapsular extension.
Clinical recommendations made in dermatology publications are frequently not supported by adequate evidence
Published in Journal of Dermatological Treatment, 2021
Kathleen M. Coerdt, Wasim Haidari, William W. Huang, Steven R. Feldman
Intervention decisions require knowing that the benefit of the intervention exceeds the costs and risks (1–3). Consider prostate-specific antigen (PSA) screening for prostate cancer. There is a reduction in disease mortality over 15 years, and the benefits of screening exceed the costs for those undergoing screening between 55 and 69 years old (4). Screening results in many false positives, leading to additional testing, potential overdiagnosis, and overtreatment, as well fear and stress on the patient (4,5). While a few may benefit from screening, all patients are placed at risk for screening costs and potential treatment-associated harms including urinary or sexual dysfunction, blood clots, and death (5). Simply knowing there is a benefit does not warrant a recommendation that screening be done in all patients; costs, risks, and benefits need to be weighed.
Sexual Behavior With Noncommercial Partners: A Concurrent Partnership Study Among Middle-Aged Female Sex Workers in China
Published in The Journal of Sex Research, 2019
Jennifer Guida, Liangyuan Hu, Hongjie Liu
Trained lab technicians collected and tested the following specimens from each consenting participant: (a) a venipuncture blood specimen for syphilitic infection and (b) vaginal swabs to test for prostate-specific antigen (PSA). Syphilitic infection was first screened using a qualitative immunoassay to detect antibodies to Treponema pallidum (Alere Determine TP test; Alere Medical Co., Ltd., Chiba Prefecture, Japan) and was confirmed by a Treponema pallidum particle agglutination test for detection of antibodies to Treponema pallidum (TPPA; Fujirebio Inc., Tokyo, Japan, or ABON Biopharm Co., Ltd., Hangzhou, China). Confirmed positive TPPA samples were tested for nontreponemal antilipoidal antibodies, using Toluidine Red Unheated Serum Test (TRUST; Wantai Biological Pharmacy Enterprise Co., Ltd., Beijing, China). FSWs who serotested positive for TPPA were classified as prevalent cases of syphilitic infection (including both previous and active syphilitic infection), because a positive test result indicates evidence of antibody to syphilis and is interpreted as a lifetime marker of infection (Seña, White, & Sparling, 2010). Those who serotested positive for both TPPA and TRUST were classified as active cases (or current cases) of syphilitic infection, including active or latent treponemal infection.
Homeostasis: apoptosis and cell cycle in normal and pathological prostate
Published in The Aging Male, 2020
Norelia Torrealba, Gonzalo Rodríguez-Berriguete, Raúl Vera, Benito Fraile, Gabriel Olmedilla, Pilar Martínez-Onsurbe, Manuel Sánchez-Chapado, Ricardo Paniagua, Mar Royuela
Prostates were obtained from: (a) histologically normal prostates (NP) obtained at autopsy (8–10 h after death) from 20 men (aged between 20 and 38 years) without histories of reproductive, endocrine, or related diseases; (b) radical prostatectomies from 86 men (aged between 52 and 74 years) with prostate cancer. Prostate cancer was detected by serum PSA (prostate specific antigen) screening and rectal examination, and diagnostic was confirmed by histopathological examination of needle biopsy cores. The median age (range) at the time of surgery was 66 (52–74). Patients were generally scheduled to have a serum PSA measure every 3 months for the first year and every 6 months thereafter. Median follow-up (range) time of the cohort was 75.9 (15.6–159.2) months, being defined as the time between the surgery and the endpoint of the study or the last record. Clinic pathological features of patients are shown in Table 1.