Do non-specific minimal signs in a biennial mammographic breast cancer screening programme need further diagnostic assessment?

Abstract

Abstract. Mammographic features such as small vague densities, indefinable microct subtle architectural distortions, alone or in combination, are non-specific appearances ior breast cancer. These features sometimes precede malignancy and a decisive strategy on how to deal with non-specific minimal signs in a breast cancer screening programme is studying the prevalence of these signs in a Dutch Breast Cancer Screening Centre and estimating the risk of participants with these signs acquiring breast cancer within 2 years, we have such a strategy. Non-specific minimal signs were seen on the mammograms of 53 of 500 (10.6%) participants, aged 50-70 years, in this programme. After retrospective analysis of the mammograms of 254 patients with screen-detected or interval carcinoma, non-specific minimal signs were detected in 77 cases. Combining the incidence of breast cancer with the difference between the expected num ber of non-specific minimal signs in the screening programme and its actual occurrence in previous mammograms of patients with breast cancer, the risk of cancer in women with these signs, additional to that of screened women in general (additional risk), is calculated as being 0.5%. Invasive breast cancer in women with previously detected non-specific minimal signs dem on strated a favourable stage at diagnosis (axillary metastasis in 23% vs 37% in cancers without these previous signs, ¿><0.05). Our strategy for follow-up in case of non-specific minimal signs remains unchanged because of the low additional risk and favourable staging, and is restricted to an invitation for the next screening round in 2 years time.

Radiological peer review of interval cancers in the East Anglian breast screening programme: what are we missing?

“…However, these diVerences were too small to be useful in improving screening sensitivity. Therefore we, as others previously, 50 were unable to identify any specific lesions particularly indicative of subsequent poor prognosis.…”

Digital mammography: what do we and what don’t we know?

“…Per Skaane in the Oslo II study at a recall rate of 3.7% for digital and 3.0% for film-screen mammography (compared to around 10% for women <50 years of age in the DMIST trial) found a much smaller, statistically not significant advantage for digital mammography in women below the age of 50 ( Table 2). To be able to take full advantage of digital mammography in women with dense breasts, it may therefore be necessary to aggressively recall even subtle findings, so-called "minimal signs" as defined in the Dutch screening program [43]. In European populationbased screening programs, however, there is a tendency to initially ignore these minimal signs in order to keep the recall rate at an acceptable low level [43].…”

“…To be able to take full advantage of digital mammography in women with dense breasts, it may therefore be necessary to aggressively recall even subtle findings, so-called "minimal signs" as defined in the Dutch screening program [43]. In European populationbased screening programs, however, there is a tendency to initially ignore these minimal signs in order to keep the recall rate at an acceptable low level [43]. …”

Identification of women with early breast cancer by analysis of p43-positive lymphocytes

“…Inclusion criteria were nonpalpable mammographic lesions in accordance with the characteristics listed in Table 1. All of these radiological criteria for potential malignancy had to appear on at least two conventional mammograms in standard projection (Sickles, 1994;Maes et al, 1997). Diffuse microcalcifications found in mammograms were eligible if accompanying risk features, such as elongated round or vermiform microcalcifications, were detected.…”

“…Increasing knowledge of high-risk groups and regular screening mammography have resulted in an improvement in the rate of detection of smaller malignant lesions (Arnesson et al, 1995;Tabar et al, 1995). However, certain minimal mammographic features, such as small vague densities, indefinable microcalcification or subtle architectural distortions, alone or in combination, can also represent non-specific indications of cancerous lesions (Sickles, 1994;Ciatto et al, 1995;Hiatt and Pasick, 1996;Maes et al, 1997). In addition, the diagnostic accuracy of mammographic screening in women under 50 with dense breast parenchyma has been questioned by some authors (Black et al, 1995;Leitch, 1995).…”