Background: The histological classification of invasive ductal carcinoma proposed by the Japanese Breast Cancer Society is based on the appearance of breast cancer invasion. However, few studies have been done to clarify the relationship between the histological classification and other parameters that represent the biological characteristics of individual breast cancer cells.
Materials and methods: We analyzed 1,025 invasive ductal carcinomas, consisting of 424 papillotubular, 330 solid-tubular and 271 scirrhous cases, with regard to the status of estrogen receptor (ER), progesterone receptor (PgR), DNA ploidy, epidermal growth factor receptor (EGFR) and p53 protein.
Results: Absence of ER and PgR, aneuploidy, EGFR positivity and p53 protein positivity were all observed significantly more frequently in solid-tubular tumors than in the other two types. In addition, the number of abnormal features with regard to these 5 biological parameters was also significantly higher in solid-tubular tumors than in the other two types.
Conclusion: Abnormalities in the biological parameters listed above were frequently found in the solid-tubular type of invasive ductal carcinoma.