Background: False-negative (FN) mammograms typically delay breast cancer diagnoses and may impact clinical outcomes. However, systematic evaluations of FN mammograms are challenging to conduct due to interval cancers' low incidence. Objective: To evaluate the rates of FN screening and diagnostic mammograms in the National Mammography Database (NMD), and to assess associations of FN rates with patient- and facility-level characteristics. Methods: This retrospective study included all screening and diagnostic mammograms in the NMD performed from January 1, 2010, to December 31, 2022. Patient- and facility-level factors were extracted from the NMD. FN mammograms were defined as those with a negative result in a patient with a tissue diagnosis of breast cancer within the subsequent 1 year. FN rates per 1000 examinations were computed. Separate multivariable analyses were performed to identify associations with FN results for screening and diagnostic examinations. Results: The analysis included 38,304,525 mammography examinations in 15,585,433 women (mean age, 58.8±11.7 years). Of 32,267,238 screening examinations, the FN rate was 1.9 (minimum, 0.7 in 2010; maximum, 2.5 from 2020 to 2022). Of 6,037,287 diagnostic examinations, the FN rate was 4.0 (minimum, 2.3 in 2010; maximum, 5.4 in 2020). In multivariable analysis for screening examinations, the likelihood of a FN examination was lower for race categories other than White (OR=0.30-0.95), higher for breast density categories other than almost entirely fatty breasts (OR=1.60-2.00), higher for women with personal (OR=3.69) or family (OR=1.29) history of breast cancer, and higher for academic or university-based facilities (OR=1.37); for diagnostic examinations, the likelihood of a FN examination was lower for race categories of Asian (OR=0.91) and Hawaiian (OR=0.77) and higher for a race category of Black (OR=1.12), lower for Hispanic patients (OR=0.70), higher for heterogeneously (OR=1.46) or extremely (OR=1.86) dense breasts, higher for women with personal (OR=7.82) or family (OR=1.31) history of breast cancer, and higher for academic or university-based facilities (OR=1.37). Conclusion: Rates of FN screening and diagnostic mammograms increased over time and showed significant associations with patient and facility characteristics. Clinical Impact: Exploration of the causes of the observed associations could inform quality assurance efforts to reduce the risk of delayed breast cancer diagnoses.

In an era of persistent and evolving cyberthreats that pose serious risks to patient safety, institutional integrity, and regulatory compliance, healthcare organizations, particularly radiology departments, must adopt a proactive stance toward cybersecurity. Radiology departments are particularly vulnerable to cyberattacks due to their dependence on often legacy and insecure digital imaging systems, as well as a reliance on network connectivity and specialized software. This AJR Expert Panel Narrative Review offers a strategic roadmap for healthcare institutions to prepare for and survive cybersecurity attacks, with a focus on the unique vulnerabilities within medical imaging systems that radiology departments must address. Real-world threats, ranging from PACS network exploitation to DICOM data manipulation, ransomware disruptions, and the consequences of inaction are examined. Emphasis is placed on practical defense mechanisms including layered security architecture, regular vulnerability assessments, employee training, and incident response simulations. The insights are intended to inform a defense-indepth strategy incorporating physical, technical, and administrative safeguards aligned with HIPAA and other regulatory standards. Overall, this guide for radiology practices seeks to align technical controls with operational resilience, to aid practices in detecting, containing, and recovering from cyber-incidents with minimal disruption to patient care.