ABSTRACT
PURPOSE: Of the hypothetical models of the carcinogenesis of breast cancer, the horizontal progression is most acceptable at the present time. According to the hypothesis, there are genetically different pathways among pure invasive ductal carcinoma (IDC), non-high grade IDC with ductal carcinoma in situ (DCIS), and high grade IDC with DCIS. The purpose of this study is to determine if there is any heterogeneity in biological behavior among these three categories. METHODS: With reversed Black nuclear grade (RBNG) in IDC component and the association of DCIS, we divided 184 breast cancer patients, who had underwent curative operations, into three groups. The patients with pure IDC were included in Group 1, non-high grade (RBNG 1 and 2) IDC with DCIS in Group 2, and high grade (RBNG 3) IDC with DCIS in Group 3. And we retrospectively analyzed and compared three groups with mean age, menopausal status, T stage, N stage, the expression rate of ER, PR, p53, and c-erbB-2, and cumulative metastasis-free survival. RESULTS: The percentage of the postmenopausal patients was significantly smaller in Group 3 (14.0%, P=0.025) than Group 1 and 2 (36.1% and 30.6%). There were significantly higher expression rates of ER and PR in Group 2 with 78.3% and 68.3%, respectively (P=0.000 and P=0.030). The 5-year metastasis- free survival rate were 70.4% in Group 1, 85.2% in Group 3, and 87.5% in Group 2. The Log Rank test in Kaplan-Meier cumulative survival curve showed the statistically significant differences among three groups (P= 0.041). CONCLUSION: We can say that there would be clinical heterogeneity among three groups classified by histopathologic findings. To apply this classification to the multi-disciplinary therapeutic modality of breast cancer, further study using a new biologic marker, which is associated with invasiveness and metastagenicity and can discrminate the three categories of breast cancers in any kind of specimen biopised preoperatively, is needed.