Investigation of Microcalcifications Visualized on Specimen Radiograms

Microcalcifications are one of the representative features of mammographically detectable breast cancers and are a very important symptom of early breast cancer. However, it is difficult to distinguish between benign and malignant microcalcifications. Therefore, we investigated the distinction between them on specimen radiograms of 22 benign and 15 malignant lesions. So far we have considered shape, cluster, numbers, presence of a linear disposition, and irregularity of size and density when diagnosing microcalcifications, but judgement was difficult on the basis of these criteria. Therefore we revised these criteria and devised a new method of judgment. On the basis of the results, we made the following conclusions. 1) Shape of microcalcifications : If casting type calcifications are found inside clustered calcifications, we judge the case as malignant. Nearly half of all granular-type calcifications and pebble-like calcifications are malignant, and therefore judgement is difficult in these cases. We consider other types of calcifications to be benign. 2) Number of calcifications per 5 mm2 and total number of calcifications : Even if we used these criteria, judgment was difficult. 3) Presence of a linear disposition : Probability of malignancy is high. 4) Irregularity of size and density : Even if we used these criteria, judgement was difficult. Statistical handling of means and standard deviations will be necessary in future. 5) The outline of the distribution and longest diameter/shortest diameter ratio : When the outline of the distribution becomes irregular and the ratio exceeds two, the probability of malignancy is high. 6) Developing density of parenchyma around clustered calcifications : The probability of malignancy is high.