Purpose: Although the breast cancer susceptibility gene (BRCA)-associated invasive breast cancer is well studied, there are limited reports on ductal carcinoma in situ (DCIS) in patients with BRCA1/2 mutations. This study aims to evaluate the differential prognostic effect of DCIS in breast cancer patients with pathologic variants of BRCA1/2 genes. Methods: Breast cancer patients who tested positive for BRCA1/2 mutations between August 2003 and January 2022 at a single tertiary referral center were retrospectively analyzed. Survival outcomes were compared between patients with both invasive ductal carcinoma (IDC) and DCIS (IDC-DCIS group, n = 121) and those with IDC alone (IDC group, n = 36). Results: Of the 157 patients, 65 (41.4%) exhibited mutations in BRCA, 90 (57.3%) in BRCA2, and 2 (1.3%) in both BRCA1/2.DCIS components were more frequently found in BRCA2 pathological variants (BRCA, 46 [38.0%] vs. BRCA2, 76 [62.4%];P = 0.030). No statistically significant difference was found in 10-year recurrence-free survival (IDC-DCIS, 89.3% vs. IDC, 83.6%; P = 0.989). Subgroup analysis indicated that the DCIS component correlated with improved survival outcomes in the BRCA1 subgroup (BRCA1 IDC-DCIS, 85.5% vs. BRCA1 IDC, 51.0%; P = 0.024). Conversely, in the BRCA2 subgroup, IDCDCIS patients exhibited a worse prognosis (BRCA1 IDC-DCIS, 85.5% vs. BRCA2 IDC-DCIS, 65.8%; P = 0.045). Conclusion The presence of a DCIS component carries varied prognostic significance in BRCA1 and BRCA2 mutations.A tailored approach may be necessary when determining treatment options for breast cancer patients with BRCA1/2 mutations based on the presence of DCIS.

Purpose: Although the breast cancer susceptibility gene (BRCA)-associated invasive breast cancer is well studied, there are limited reports on ductal carcinoma in situ (DCIS) in patients with BRCA1/2 mutations. This study aims to evaluate the differential prognostic effect of DCIS in breast cancer patients with pathologic variants of BRCA1/2 genes. Methods: Breast cancer patients who tested positive for BRCA1/2 mutations between August 2003 and January 2022 at a single tertiary referral center were retrospectively analyzed. Survival outcomes were compared between patients with both invasive ductal carcinoma (IDC) and DCIS (IDC-DCIS group, n = 121) and those with IDC alone (IDC group, n = 36). Results: Of the 157 patients, 65 (41.4%) exhibited mutations in BRCA, 90 (57.3%) in BRCA2, and 2 (1.3%) in both BRCA1/2.DCIS components were more frequently found in BRCA2 pathological variants (BRCA, 46 [38.0%] vs. BRCA2, 76 [62.4%];P = 0.030). No statistically significant difference was found in 10-year recurrence-free survival (IDC-DCIS, 89.3% vs. IDC, 83.6%; P = 0.989). Subgroup analysis indicated that the DCIS component correlated with improved survival outcomes in the BRCA1 subgroup (BRCA1 IDC-DCIS, 85.5% vs. BRCA1 IDC, 51.0%; P = 0.024). Conversely, in the BRCA2 subgroup, IDCDCIS patients exhibited a worse prognosis (BRCA1 IDC-DCIS, 85.5% vs. BRCA2 IDC-DCIS, 65.8%; P = 0.045). Conclusion The presence of a DCIS component carries varied prognostic significance in BRCA1 and BRCA2 mutations.A tailored approach may be necessary when determining treatment options for breast cancer patients with BRCA1/2 mutations based on the presence of DCIS.

Purpose: Although the breast cancer susceptibility gene (BRCA)-associated invasive breast cancer is well studied, there are limited reports on ductal carcinoma in situ (DCIS) in patients with BRCA1/2 mutations. This study aims to evaluate the differential prognostic effect of DCIS in breast cancer patients with pathologic variants of BRCA1/2 genes. Methods: Breast cancer patients who tested positive for BRCA1/2 mutations between August 2003 and January 2022 at a single tertiary referral center were retrospectively analyzed. Survival outcomes were compared between patients with both invasive ductal carcinoma (IDC) and DCIS (IDC-DCIS group, n = 121) and those with IDC alone (IDC group, n = 36). Results: Of the 157 patients, 65 (41.4%) exhibited mutations in BRCA, 90 (57.3%) in BRCA2, and 2 (1.3%) in both BRCA1/2.DCIS components were more frequently found in BRCA2 pathological variants (BRCA, 46 [38.0%] vs. BRCA2, 76 [62.4%];P = 0.030). No statistically significant difference was found in 10-year recurrence-free survival (IDC-DCIS, 89.3% vs. IDC, 83.6%; P = 0.989). Subgroup analysis indicated that the DCIS component correlated with improved survival outcomes in the BRCA1 subgroup (BRCA1 IDC-DCIS, 85.5% vs. BRCA1 IDC, 51.0%; P = 0.024). Conversely, in the BRCA2 subgroup, IDCDCIS patients exhibited a worse prognosis (BRCA1 IDC-DCIS, 85.5% vs. BRCA2 IDC-DCIS, 65.8%; P = 0.045). Conclusion The presence of a DCIS component carries varied prognostic significance in BRCA1 and BRCA2 mutations.A tailored approach may be necessary when determining treatment options for breast cancer patients with BRCA1/2 mutations based on the presence of DCIS.

Breast Neoplasms ; Breast ; Cohort Studies ; Estrogens ; Follow-Up Studies ; Genes, BRCA1 ; Genes, BRCA2 ; Hereditary Breast and Ovarian Cancer Syndrome ; Humans ; Mastectomy, Segmental ; Ovarian Neoplasms ; Prospective Studies ; Recurrence ; Risk Factors ; Unilateral Breast Neoplasms

Purpose: Breast cancer is known to be influenced by genetic and environmental factors, and several susceptibility genes have been discovered. Still, the majority of genetic contributors remain unknown. We aimed to analyze the plasma proteome of breast cancer patients in comparison to healthy individuals to identify differences in protein expression profiles and discover novel biomarkers. Methods: This pilot study was conducted using bioresources from Seoul National University Bundang Hospital’s Human Bioresource Center. Serum samples from 10 breast cancer patients and 10 healthy controls were obtained. Liquid chromatography-mass spectrometry analysis was performed to identify differentially expressed proteins. Results: We identified 891 proteins; 805 were expressed in the breast cancer group and 882 in the control group. Gene set enrichment and differential expression analysis identified 30 upregulated and 100 downregulated proteins in breast cancer. Among these, 10 proteins were selected as potential biomarkers. Three proteins were upregulated in breast cancer patients, including cluster of differentiation 44, eukaryotic translation initiation factor 2-α kinase 3, and fibronectin 1. Seven proteins downregulated in breast cancer patients were also selected: glyceraldehyde-3-phosphate dehydrogenase, α-enolase, heat shock protein member 8, integrin‑linked kinase, tissue inhibitor of metalloproteinases-1, vasodilatorstimulated phosphoprotein, and 14-3-3 protein gamma. All proteins had been previously reported to be related to tumor development and progression. Conclusion The findings suggest that plasma proteome profiling can reveal potential diagnostic biomarkers for breast cancer and may contribute to early detection and personalized treatment strategies. A further validation study with a larger sample cohort of breast cancer patients is planned.

Purpose: Estrogen receptor (ER) expression in breast cancer plays an essential role in carcinogenesis and disease progression. Recently, tumors with low level (1%-10%) of ER expression have been separately defined as ER low positive (ERlow). It is suggested that ERlow tumors might be morphologically and behaviorally different from tumors with high ER expression (ERhigh). Materials and Methods: Retrospective analysis of a prospective cohort database was performed. Patients who underwent curative surgery for early breast cancer and had available medical records were included for analysis. Difference in clinicopathological characteristics, endocrine responsiveness and five-year recurrence-free survival was evaluated between different ER subgroups (ERhigh, ERlow, and ER-negative [ER–]). Results: A total of 2,162 breast cancer patients were included in the analysis, Tis and T1 stage. Among them, 1,654 (76.5%) were ERhigh, 54 (2.5%) were ERlow, and 454 (21.0%) were ER- patients. ERlow cases were associated with smaller size, higher histologic grade, positive human epidermal growth factor receptor 2, negative progesterone receptor, and higher Ki-67 expression. Recurrence rate was highest in ER– tumors and was inversely proportional to ER expression. Recurrence-free survival was not affected by hormonal therapy in the ERlow group (p=0.418). Conclusion ERlow breast cancer showed distinct clinicopathological features. ERlow tumors seemed to have higher recurrence rates compared to ERhigh tumors, and they showed no significant benefit from hormonal therapy. Future large scale prospective studies are necessary to validate the treatment options for ERlow breast cancer.