Factors affecting prostate cancer detection through asymptomatic PSA testing in primary care in England: Evidence from the 2018 National Cancer Diagnosis Audit

Background Prostate-Specific Antigen (PSA) is used in primary care for prostate cancer detection, either for symptomatic assessment or asymptomatic testing following an informed decision. Aim To estimate the proportion of prostate cancer cases diagnosed following asymptomatic PSA testing, and patient and practice factors influencing this route. Design and setting 2018 English National Cancer Diagnosis Audit (NCDA) data were analysed, with linkage to the national cancer registry, practice-level Quality Outcomes Framework (QOF), and General Practice Patient Survey (GPPS) data. All 2018 NCDA patients with a diagnosis of prostate cancer were included (n = 9,837). Method Patients with recorded biomarker testing and no recorded symptoms prior to diagnosis were classified as asymptomatic PSA detected prostate cancer. Patient (age, ethnicity, deprivation, co-morbidities) and GP practice (geographical location, area deprivation, list size, urgent suspected cancer referral rate, QOF outcomes, GPPS results) factors were analysed for association with asymptomatic PSA testing using mixed effects logistic regression models. Results 1,884 out of 9,837 (19%) prostate cancer cases were detected following asymptomatic PSA testing, 982 (52.1%) of whom were patients aged 50-69 years. Younger age, non-White ethnicity, lower deprivation, and lower co-morbidity count were associated with an increased likelihood of diagnosis following asymptomatic PSA testing. There was a 13-fold variation between practices in the odds of asymptomatic PSA-detected cases, without clear explanatory GP practice-level factors. Conclusion One in five patients with prostate cancer in England are diagnosed after asymptomatic PSA testing in primary care, with large variation in asymptomatic PSA detection between GP practices.