Comparison of the Accuracy of Breast Cytological Diagnosis at Seven Institutions in Southern Fukuoka Prefecture, Japan

Abstract

Cytological examination is inexpensive and relatively simple to carry out and deserves utilization in breast cancer screening. We investigated the status of cytological diagnosis at seven facilities in southern Fukuoka Prefecture, Japan. We collected data on the criteria for cytological judgments and status of breast cytological diagnosis at seven different facilities in this region. Among 5693 individuals who underwent breast cytological examination, analyses were conducted on 1250 individuals (22.0%) in whom cytological diagnoses were confirmed by histological diagnoses. Among these patients, cytological diagnosis had an absolute sensitivity of 71.9%, a specificity of 76.0%, a false-negative value of 6.7% and a false-positive value of 0.08%. At three facilities with relatively large numbers of cases (>300), excluding a facility for specialized breast disease, similar trends of high complete sensitivity (94.3, 95.6 and 97.1%, respectively) and low absolute sensitivity (60.4, 74.8 and 57.2%, respectively) were found. No false-negative or false-positive cases were seen in individual facilities with relatively low numbers of cases (<150). The accuracy of cytological diagnosis at the facilities we surveyed was relatively high compared with the goals of assessment of diagnostic accuracy. However, the performance was dependent on the facility type, i.e. number of cases, staff involved and whether it was specialized or not, making the diagnosis specific for this region. We recommend that management of the accuracy of cytological diagnosis be undertaken jointly by multiple facilities to establish systems in Japan that lead to more useful diagnostic tools.