One-stop diagnostic breast clinics: how often are breast cancers missed?

The aim of this study was to estimate the number of patients discharged from a symptomatic breast clinic who subsequently develop breast cancer and to determine how many of these cancers had been ‘missed' at initial assessment. Over a 3-year period, 7004 patients were discharged with a nonmalignant diagnosis. Twenty-nine patients were subsequently diagnosed with breast cancer over the next 36 months. This equates to a symptomatic ‘interval' cancer rate of 4.1 per 1000 women in the 36 months after initial assessment (0.9 per 1000 women within 12 months, 2.6 per 1000 women within 24 months). The lowest sensitivity of initial assessment was seen in patients of 40–49 years of age, and these patients present the greatest imaging and diagnostic challenge. Following multidisciplinary review, a consensus was reached on whether a cancer had been missed or not. No delay occurred in 10 patients (35%) and probably no delay in 7 patients (24%). Possible delay occurred in three patients (10%) and definite delay in diagnosis (i.e., a ‘missed' cancer) occurred in only nine patients (31%). The overall diagnostic accuracy of ‘triple' assessment is 99.6% and the ‘missed' cancer rate is 1.7 per 1000 women discharged

Measuring the accuracy of diagnostic imaging in symptomatic breast patients : team and individual performance

Objective: The combination of mammography and/or ultrasound remains the mainstay in current breast cancer diagnosis. The aims of this study were to evaluate the reliability of standard breast imaging and individual radiologist performance and to explore ways that this can be improved. Methods: A total of 16 603 separate assessment episodes were undertaken on 13 958 patients referred to a specialist symptomatic breast clinic over a 6 year period. Each mammogram and ultrasound was reported prospectively using a five-point reporting scale and compared with final outcome. Results: Mammographic sensitivity, specificity and receiver operating curve (ROC) area were 66.6%, 99.7% and 0.83, respectively. The sensitivity of mammography improved dramatically from 47.6 to 86.7% with increasing age. Overall ultrasound sensitivity, specificity and ROC area was 82.0%, 99.3% and 0.91, respectively. The sensitivity of ultrasound also improved dramatically with increasing age from 66.7 to 97.1%. Breast density also had a profound effect on imaging performance, with mammographic sensitivity falling from 90.1 to 45.9% and ultrasound sensitivity reducing from 95.2 to 72.0% with increasing breast density. Conclusion: The sensitivity ranges widely between radiologists (53.1–74.1% for mammography and 67.1–87.0% for ultrasound). Reporting sensitivity was strongly correlated with radiologist experience. Those radiologists with less experience (and lower sensitivity) were relatively more likely to report a cancer as indeterminate/uncertain. To improve radiology reporting performance, the sensitivity of cancer reporting should be closely monitored; there should be regular feedback from needle biopsy results and discussion of reporting classification with colleagues