Abstract
The purpose of this study is to establish an objective and reliable method of the determination of malignancy by mammography. The preoperative mammograms were analysed and the findings were scored according to the rate of each abnormality. The histopathological findings were compared to the mammographical ones. One hundred and fourty-six patients with primary breast cancer and 84 individuals with negative (or benign) biopsy were subjected for this study.
1. Mammographical findings. The rate of each malignant feature on the mammograms were as follows : increased radiodensity (80.1%), irregular radiodensity (78.1%), margin irregularity or spicula (69.9%), Leborgne's law (43.2%), fine calcification (24.7%), comet sign (17.1%), retraction of the supporting ligament (41.8%), dilatation of the vessels or hypervascularization (36.3%) and thickening of the skin (11.1%).
For determination of the tumor malignancy those abnormalities appearing around the tumor margin seemed to be highly pathognomonic. Details of the soft x-ray films of large slices of a resected specimen were also studied.
2. Histopathological findings. Increased and irregular radiodensity was highly correlated with population of both tumor cells and stroma cells as well as occurrence of necrosis or degeneration of stroma cells. The former findings were proved by the fact that the higher was the rate of stroma cells in a specimen, the more increase the radiodensity on films. The spicula and the comet sign immediately representetd infiltration of scirrhous cells into adjacent fat tissues or into ductus.
Retraction of the supporting ligament was produced by carcinoma infiltration with more or less proliferation of fibrous connective tissue. Thickening of skin layer observed on mammogram was due not only to the dermis thickening but evenly to that of subcutaneous tissues.
3. Scoring of the mammographical findings. For rate of each abnormality, such as increased radiodensity, irregular radiodensity, margin irregularity (or spicula), Leborgne's law, fine calcification and comet sign, which were all a sign directing to malignancy, the score ranging from points 6 to point 1 was given. Those findings which may be indirect sign of malignancy were evaluated with the score from points 3 to point 1. They were retraction of the supporting ligament, dilatation of the vessels or hypervascularization and thickening of the skin, respectively. This method of scoring was a good measure to the determination of the malignancy of a breast cancer.
