Clinicopathological Follow-up of Breast DCIS Diagnosed on Biopsies: A Single Institutional Study of 575 Patients

Stratifying ductal carcinoma in situ (DCIS) patients into different upgrading risk groups is important in exploiting more precise therapeutic options. Evaluation of estrogen receptor/progesterone receptor/human epidermal growth factor receptor 2 (ER/PR/HER2) status and axillary lymph node metastatic status for DCIS and their upgraded invasive counterparts can also provide diagnostic and therapeutic implications. We retrospectively studied 575 patients with first-time diagnosis of DCIS on biopsies, and followed up their final diagnosis, ER/PR/HER2 status, and axillary lymph node involvement on excisions. As a result, biopsy-diagnosed DCIS had an overall 19.1% risk to be upgraded on subsequent excisions, with 4.7% being upgraded to microinvasive carcinoma (pT1mi) and 14.4% to overt invasive carcinoma (⩾pT1a). Factors significantly associated with higher upgrading risk on multivariate analysis include biopsy guidance by ultrasound ( P <.001), DCIS with suspicious microinvasion ( P < .001), and DCIS diagnosed in left breast ( P = .026). DCIS diagnosed in younger patients (⩽40 years old) or DCIS with high nuclear grade showed higher upgrading risk only on univariate analysis. About 80% ER + /PR + and ER−/PR− DCIS remained the same ER/PR status after being upgraded, and ER + /PR − DCIS had the highest risk (63.6%) of having HER2 amplification in upgraded invasive carcinoma. For upgraded DCIS, microinvasive carcinoma was more likely to have HER2 amplification (50%) than overt invasive carcinoma (29.5%). Besides, pure DCIS had a low risk of axillary lymph node macrometastasis (0.74%), while the risk increased in DCIS with microinvasion (4.4%) and was highest in overt invasive carcinoma (14.7%). The findings of this study are clinically relevant with respect to criteria that might be used in selecting patients for de-escalation trials.

Breast Microinvasive Carcinoma With Different Morphologies: Analysis of Clinicopathologic Features of 121 Cases

Purpose: To investigate the clinicopathological features of patients with breast microinvasive carcinoma (MI). Methods: The clinical data of 121 cases with breast MI were retrospectively collected. The whole tumor in each case was stained with hematoxylin and eosin (H&E) for pathological evaluation. The relationships among size of tumor, histological grade, tumor-infiltrating lymphocytes (TILs), the number of MIs, type of MI, and lymph node metastasis were analyzed. Results: It was revealed that 86% of the cases had high-grade ductal carcinoma in situ (DCIS) and 63.6% had multiple MIs. The larger size of the tumors, the higher the grade of DCIS, the more the number of MIs; 3.3% of cases had rich TILs (lymphocyte/stroma > 30%) in the DCIS, and 26.5% had rich TILs in MIs. The type A of MIs is characterized by single cells and small clusters of solid cells. Tumor cells in type B of MIs can form glandular ducts. Formal grading of microinvasive is challenging/impossible due to its limited size precluding a representative mitotic count. But nuclear grade and tubule (differentiation) grades can be reported. In addition, 72.7% of cases had type A of MIs and 27.3% of cases had type B of MIs. Type B was found to be highly accompanied by moderate-grade DCIS. Only 6.6% of patients with MI had lymph node metastasis, which was mainly related to MIs with less TILs. Conclusion: Breast MI is easy to occur in high-grade DCIS, and multiple infiltration foci may be observed in case with tumor size of higher than 3.5 cm. Microinvasive carcinoma with poor TILs maybe a risk factor for lymph node metastasis in patient with DCIS-Mi.