Cohort Of Early Breast Cancer Patients Research Articles

Safety of autologous fat grafting in breast cancer: a multicenter Italian study among 17 senonetwork breast units autologous fat grafting safety: a multicenter Italian retrospective study.

Autologous fat grafting (AFG), defined as the re-implant to the breast of fat tissue from different body areas, has been firstly applied to esthetic plastic surgery and then has moved to reconstructive surgery, mainly used for scar correction and opposite breast altering. Nevertheless, due to the potentially unsafe stem-like properties of adipocytes at the tumoral bed level, no clear evidence of the procedure's oncological safety has been clearly documented at present. We retrospectively collected data of early breast cancer (BC) patients from 17 Italian Breast Units and assessed differences in terms of locoregional recurrence rate (LRR) and locoregional recurrence-free survival (LRFS) between patients who underwent AFG and patients who did not. Differences were analyzed in the entire cohort of invasive tumors and in different subgroups, according to prognostic biological subtypes. With a median follow-up time of 60months, LRR was 5.3% (n = 71) in the matched population, 3.9% (n = 18) in the AFG group, and 6.1% (n = 53) in the non-AFG group, suggesting non-inferiority of AFG (p = 0.084). Building Kaplan-Meier curves confirmed non-inferiority of the AFG procedure for LRFS (aHR 0.73, 95% CI 0.41-1.30, p = 0.291). The same effect, in terms of LRFS, was also documented among different biological subtypes (luminal-like group, aHR 0.76, 95% CI 0.34-1.68, p = 0.493; HER2 enriched-like, aHR 0.89, 95% CI 0.19-4.22, p = 0.882; and TNBC, aHR 0.61, 95% CI 0.12-2.98, p = 0.543). Our study confirms in a very large, multicenter cohort of early BC patients that, aside the well-known benefits on the esthetic result, AFG do not interfere negatively with cancer prognosis.

Bone recurrence in early breast cancer patients: The paradox of aromatase inhibitors induced bone resorption.

Despite the increase in chances of cure for early breast cancer (EBC) patients, approximately 20-45% of them will experience a disease recurrence, particularly bone metastases in 60-80% of cases, which occur more frequently in luminal subtypes. Endocrine therapy (ET) has always been the milestone of adjuvant treatment for hormone receptor-positive EBC patients, leading to indubitable reduction of disease recurrence risk. However, adjuvant aromatase inhibitors (AIs) therapy may promote a progressive decrease in bone mineral density (BMD), which can lead to osteoporosis. The increased bone resorption associated with osteoporosis may provide fertile soil for cancer growth and accelerate the development of bone metastases. In this single-institution cohort study, we performed a retrospective analysis of "luminal-like" EBC patients who experienced bone recurrence after a subsequent disease free interval. The aim of the study was to evaluate the median time to skeletal recurrence (TSkR). 143 patients experienced bone recurrence. Median TSkR was 54 months (95%CI: 45-65). Among patients who received adjuvant AIs median TSkR was 35 months (95%CI: 25-54), while among patients who did not was 61 months (95%CI: 50-80) (HR = 1.45 [95%CI: 0.97-2.17], p =0.0644). After adjusting for TNM stage (AJCC 8th edition), adjuvant AIs treatment was significantly related to a shorter TSkR (HR = 1.60 [95%CI: 1.06-2.42], p =0.0244). Adjuvant Tamoxifen, adjuvant AIs/Tamoxifen and no-treatment did not revealed to be associated to TSkR. In this cohort of EBC patients with bone recurrence, AIs treatment seems to be related to a shorter TSkR. AIs-induced bone resorption might represent the underlying mechanism.

Abstract 2726: Characterization of immune microenvironment and heterogeneity in breast cancer subtypes

Abstract Despite ongoing advancements in the clinical management of breast cancer (BC), the variability in the response to treatment requires continued understanding of the molecular biology of this disease. Receptor status for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) along with pathological features dictate the course of therapy. Tumor cells in BC are phenotypically diverse between and within patients due to underlying differences in their cellular biology. This heterogeneity in the expression of key molecular targets renders some tumor cells resistant to therapy. While the etiology of intra-tumor heterogeneity is under investigation, it is equally important to characterize the heterogeneous nature of the tumor microenvironment as both of these compartments are engaged in the molecular crosstalk; with the latter known to contribute to tumor progression. Traditionally considered to be immunologically cold, recent advances have demonstrated that some BC subtypes elicit immunological response. However, further research is warranted to broadly illustrate the immune cell contexture in BC in a spatial context. In this study, the immune microenvironment was characterized through proteomic analysis using NanoString's GeoMX Digital Spatial Profiling (DSP) platform, in a cohort of early BC patients. This cohort consists of Luminal A, Luminal B, Basal, and HER2 BC subtypes. Correlation of proteomic and genomic data will reveal the role of genomic alterations in differential immune response. Protein markers were analyzed in both the tumor microenvironment (TME) and tumor compartments with beta-2-microglobulin, CD40, and CD11 significantly expressed in the TME compartment while PanCK, ERalpha, and HER2 were enriched in the tumor. Interestingly, CD127 was also expressed in the tumor compartment, indicating infiltration by memory T cells. Through this study we spatially characterize the immune microenvironment in BC subtypes, providing further evidence against the “immunologically cold” view of this disease. In addition, we demonstrate the potential clinical use of this novel platform in diagnosing and better stratifying BC patients based on spatial heterogeneity in tumor and TME. Citation Format: Drashti Jain, Linda Liao, Megan Hopkins, Mary Anne Quintayo, Vida Talebian, Jane Bayani, Alison Cheung, Martin Yaffe, John Bartlett, Melanie Spears. Characterization of immune microenvironment and heterogeneity in breast cancer subtypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2726.

Abstract PS6-54: Prognostic significance of residual micrometastatic axillary involvement with complete pathologic breast response after neoadjuvant chemotherapy for early breast cancer

Abstract Introduction and objectives Pathologic complete response (pCR, ypT0/Tis ypN0) after neoadjuvant chemotherapy (nCT) in early breast cancer (BC) is associated with higher survival rate. Controversy about the prognostic significance of low-volume or micrometastatic axillary residual disease (ypN1mi-RD) exists. Essentially, it is considered equivalent to high-volume nodal disease (ypN1/ypN2-RD) for the indication of lymphadenectomy after nCT. Clarifying ypN1mi-RD prognostic value would be useful for planning adjuvant therapy. Thus, our objective was to assess the prognostic significance of ypN1mi-RD in the context of primary breast tumor pCR. Material and methodsRetrospective, single-center analysis of a cohort of early BC patients treated with nCT between 2010 and 2018 who achieved breast pCR (ypT0/Tis) combined with axillary pCR (ypN0) or ypN1mi-RD or ypN1/ypN2-RD. Cases with pre-nCT sentinel lymph node biopsy were excluded. 5-year disease-free survival (DFS) and overall survival (OS) were analyzed using Cox regression models.ResultsAmong 470 early BC patients treated with nCT, 134 (28.5%) had in-breast pCR, of whom: 97 (20.6%) were ypN0; 7 (1.5%) were ypN1mic; 10 (2.1%) were ypN1 and 5 (1.1%) were ypN2. Clinicopathological characteristics of the groups are shown in the Table. Median follow-up: 33 months. Eight patients relapsed, 4 of 97 with nodal pCR and 4 of 22 with axillary residual disease: 2/7 ypN1mic; 1/10 ypN1 and 1/5 ypN2. Patients who relapsed predominantly presented pre-nCT clinical lymph node involvement, hormone receptor negativity, ki67<20% and absence of complete clinical response (100%). Globally, patients with axillary residual disease had lower DFS rates (95% vs. 69%, p = 0.03), with no apparent differences between ypN1-RD vs. ypN2-RD in the subgroup analysis (75% vs. 80%, respectively). ypN1mic-RD patients showed the poorest DFS (33%, p <0.01). In the multivariable analysis, ypN1mic-RD had worse DFS than nodal pCR (HR 13.98, 95%CI 1.95-100.24, p = 0.01), but no differences were observed between the low and high-volume residual axillary disease categories (HR 0.24, 95%CI 0.03-1.74, p = 0.16). Due to the low rate of events, no differences in terms of OS were observed (p = 0.77).Conclusion In the context of in-breast pCR after nCT for early BC, ypN1mic-RD not only presented a higher risk of relapse than nodal pCR, but also was not associated with a better prognosis than that observed for ypN1/ypN2-RD. Micrometastatic axillary residual disease behaves as an independent adverse prognostic factor, comparable to high-volume axillary residual disease, and might be considered as a factor for the indication of post-nCT adjuvant treatment. Table. Clinicopathologic characteristics of the cohort of early BC patients treated with nCT betweenypT0/TisypT0/TisypN1mic-RDypN1/N2-RDpCR(N=7)(N=15)(N=97)Age (median, range)49 (25-83)47 (40-77)47 (25-80)Menstrual statusPostmenopausal3 (42,8%)4 (26,7%)42 (43,3%)Premenopausal4 (57,1%)11 (73,3%)55 (56,7%)ECOGECOG 05 (71,4%)13 (86,7%)78 (80,4%)ECOG 12 (28,5%)2 (13,3%)19 (19,6%)Histologic subtypeInvasive ductal carcinoma7(100,0%)14 (93,3%)95 (97,9%)Other subtypes0 (0,0%)1 (6,7%)2 (2,0%)Histologic gradeGrade 10 (0,0%)0 (0,0%)1 (1,0%)Grade 23 (42,9%)5 (33,3%)17 (17,5%)Grade 34 (57,1%)8 (53,3%)67 (69,1%)Unknown0 (0,0%)2 (13,3%)0 (0,0%)cTcT11 (14,2%)4 (26,7%)8 (8,2%)cT24 (57,1%)5 (33,3%)63 (64,9%)cT32 (28,6%)6 (40,0%)24 (24,7%)cT4a-d0 (0,0%)0 (0,0%)2 (2,1%)cNcN01 (14,3%)0 (0,0%)27 (27,8%)cN13 (42,9%)5 (33,3%)34 (35,1%)cN21 (14,3%)6 (40,0%)24 (24,7%)cN32 (28,6%)4 (26,7%)11 (11,3%)Molecular subtypeHR+ HER2-1 (14,3%)8 (53,3%)11 (11,3%)HR+ HER2+3 (42,9%)1 (6,7%)30 (30,9%)HR- HER2+2 (28,6%)3 (20,0%)21 (21,6%)TNBC1 (14,3%)3 (20,0%)35 (36,1%)Breast surgeryConservative7 (100%)10 (66,7%)67 (69,1%)Mastectomy0 (0,0%)5 (33,3%)30 (30,9%)Nodal surgerySLN biopsy0 (0,0%)0 (0,0%)22 (22,7%)ALND7 (100,0%)15 (100,0%)75 (77,3%)ypTypT05 (71,4%)7 (46,7%)80 (82,5%)ypTis2 (28,6%)8 (53,3%)17 (17,5%)Relapse typeMetastatic2 (28,6%)2 (28,6%)2 (2,1%)Local/contralateral0 (0,0%)0 (0,0%)2 (2,1%)Deaths0 (0,0%)1 (6,7%)1 (1,0%)BC: breast cancer. HR: hormone receptor. nCT: neoadjuvant chemotherapy. pCR: pathologic complete response. SLN: sentinel lymph node. TN: triple negative. ypN1mic-RD: micrometastatic axillary residual disease. ypN1/N2-RD: high-volume axillary residual disease. Citation Format: Esmeralda García-Torralba, Maria Esperanza Guirao Garcia, Pilar de la Morena Barrio, Alejandra Ivars Rubio, Elena Garcia Martinez, Elisa Garcia Garre, Gema Marin Zafra, Beatriz Alvarez Abril, Esther Navarro Manzano, Francisco Ayala de la Peña. Prognostic significance of residual micrometastatic axillary involvement with complete pathologic breast response after neoadjuvant chemotherapy for early breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS6-54.

BMI is an independent prognostic factor for late outcome in patients diagnosed with early breast cancer: A landmark survival analysis

BMI is an independent prognostic factor for late outcome in patients diagnosed with early breast cancer: A landmark survival analysis

Abstract P4-12-07: CCND1 amplification in early breast cancer patients: Correlation with subtypes and prognosis

Abstract Background: Mechanisms of progress and recurrence of early breast cancer (BC) have gained importance since several targeted therapeutic options in metastatic breast cancer have been introduced over the last years, especially in hormone receptor positive BC. This study investigates the amplification of cell cycle regulator cyclin D1 gene (CCND1) amplification as one possible progression mechanism. Patients & Methods: Patients from an unselected cohort of early BC patients were included into this study. A tissue microarray (TMA) was available for n=832 patients with early breast cancer. CCND1 amplification was assessed after FISH (Abbott Vysis LSI CCND1 SpectumOrange/CEP11 SpectrumGreen Probes Kit). A CCND1/CEP11-ratio ≥ 2.0 was considered as amplification. Staining was successful in 545 tumor cores. Amplification results were correlated with clinical patient and tumor characteristics and survival analyses were performed with regard to distant disease free survival and overall survival. Results: CCND1 amplification was found in 13.6% of patients. Triple negative, luminal A like, luminal B like and HER2 positive tumors were amplified in 7.5%, 7.8%, 18.6% and 15.7% respectively (p = 0.010). CCDN1 amplification was significantly associated with a higher grading and a higher body mass index. Furthermore an amplification was seen more frequently in lobular BC and ductal BC than other histological subtypes. Survival analysis showed a reduced DDFS for patients with CCDN1-amplification. 5 year DDFS rates were 90.6% for non-amplified tumors and 86.0% for amplified tumors (p, log-rank =0.066 ). 5 year OS rates were 93.0% for non-amplified tumors and 90.1% for amplified tumors (p, log-rank =0.119). Adjusted for age, tumor size, nodal status and molecular subtype, cox regression showed HR of 1.3 (95% CI: 0.76-2.5, p=0.46) for DDFS and a HR of 1.33 (95% CI: 0.7-2.53, p=0.38) for OS. Conclusion: With a 13.6% prevalence in all breast cancer patients, mainly present in luminal B like cancers, CCND1-amplification is a genetic aberration associated with an unfavorable prognosis. Within hormone receptor positive women CCDN1 amplification might play a role in treatment resistance mechanisms in early breast cancer patients. Citation Format: Hanf DC, Fasching PA, Villalobos IE, Gasparyan A, Wachter D, Santiago A, Guzman R, Weihbrecht S, Hanf V, Hartmann A, Beckmann MW, Press MF. CCND1 amplification in early breast cancer patients: Correlation with subtypes and prognosis [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-12-07.

Abstract P3-07-15: Prosigna® subtype correlation is a strong predictor of response to neoadjuvant chemotherapy (NAC) in early breast cancer (EBC) study

Abstract Background: Prosigna's ROR score was demonstrated as a strong predictor of response to NAC in a representative cohort of EBC patients including HR+/HER2- N0-N1 patients.1 Given that the ROR score is partially derived from the correlation of the tumor's expression profile to that of the four prototypical intrinsic subtypes, we determined the relative strength of the association between each subtype correlation and the likelihood of response to NAC. Methods: We analyzed 294 FFPE breast cancer samples from pts treated with NAC (anthracyclines and taxanes) in a multi-center Spanish cohort. The Prosigna Assay was performed on the NanoString nCounter® Dx Analysis System at HU Virgen de la Victoria de Málaga/CIMES-UMA. Pathologic complete response (pCR) was used as the primary endpoint for this study and was determined using the Miller and Payne scoring criteria. Results: Mean patient age in this population was 50 (±11yr). Apart from targeted therapy, all patients received a standard neoadjuvant treatment regimen consisting of 8-12 cycles of anthracyclines and taxanes. 58% of patients were HR+/HER2- while 24% were classified as HER2+ and 18% were TNBC patients. Of the 311 pts samples previously tested, subtype correlation data was available for 294. Overall subtype concordance between IHC and Prosigna was 72% (K=0.66). The overall pCR rate in this population was 24.9%. Prosigna subtype breakdown in the full study population was 60 Luminal A, 118 Luminal B, 69 HER2-enriched and 47 Basal-like with response rates of 7.2%, 7.2%, 46.2% and 57.4%, respectively. We found that in all study populations, subtype correlation was a strong predictor of response to NAC. Tumors with expression profiles that correlated well with the Luminal prototypical centroids were found to be largely unresponsive to NAC (Luminal A Odds ratio=0.074 per unit increase, p<0.0001; Luminal B Odds ratio=0.059 per unit increase, p<0.0001). Conversely, higher HER2E and Basal-like correlations were associated with increased probability of response (HER2E Odds ratio=11.2 per unit increase, p<0.0001; Basal-like Odds ratio=9.0 per unit increase, p<0.0001). Increased proliferation-score (p-score) was also associated with increased probability of response to NAC (Odds ratio=3.43 per unit increase, p<0.0001). Conclusions: In a representative cohort of breast cancer patients, both the magnitude of the subtype correlation to the prototypical centroids as well as p-score, as determined by the Prosigna Assay, were strong predictors of response to NAC. This data underlines the importance of molecular testing for optimal systemic therapy indications in EBC. 1Rodriguez B, Lavado Fernandez A, Ribelles N, et al. Prosigna (PAM50) to predict response to neoadjuvant chemotherapy (NAC) in HR+/HER2- early breast cancer (EBC) patients. J Clin Oncol 33, 2015 (suppl; abstr 11049). Citation Format: Chica Parrado R, Jiménez-Rodríguez B, Sánchez Rovira P, Álvarez M, Vicioso L, Fernandez AI, de Luque V, José Lozano M, Villar E, Zarcos I, Ramírez C, González-Hermoso C, Jeiranian A, Dowidar N, Schaper C, Buckingham W, Ferree S, Ribelles N, Rodrigo I, Prat AP, Alba E. Prosigna® subtype correlation is a strong predictor of response to neoadjuvant chemotherapy (NAC) in early breast cancer (EBC) study. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-15.

Abstract P1-14-12: Validation of residual cancer burden index (RCB) as a prognostic tool in patients with early breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC): Comparison of RCB and Miller & Payne system (M&P)

Abstract Pathological evaluation of response after NAC is a controversial issue. M&P has been for years the most widely employed score. Recently RCB index, a new system including axillary evaluation, seems to improve prognostic discrimination. PURPOSE: The aim of this study was to validate the RCB index as a method to define prognosis in a reallife cohort of EBC patients treated with NAC and compare it to M&P system. METHODS: We performed a retrospective analysis of our database. Patients with stage I-III considered candidate for NAC between January 2003 and August 2011 were included. RCB and M&P were calculated as previously published. Hormone receptor expression (RH), and Her2 were assessed following international guidelines. The Harell c-index and Roc curves were used to compare the prognostic value of RCB and M&P. Clinical, therapeutic and pathological data were obtained from medical records. A correlation with disease-free survival (DFS) and overall survival (OS) was done using the Kaplan-Meier method and Cox regression model. RESULTS: 333 patients were included in this study. Distribution of breast cancer subtypes was: luminal 50.9%, Her2+ 31% and triple negative 18.1%. Mean tumour size was 42.3 mm. The majority of the patients had histhological grade II-III tumours (87.3%), with N stage 0-1 (97.3%). 87.4% received anthracycline and taxane-based NAC, associated to trastuzumab in her 2+ patients. Pathological complete response was 14% for the global population, being 30% for TN and 21.3% Her2+ subtypes. With a median follow-up of 56.3 months, DFS and OS at 5 years were as follows: RCB-0 93.6% and 97.9%, RCB-I 84.2% and 98.2%, RCB-II 79.1% and 89.5%, RCB-III 38.3% and 63.6%. Harell c-index value of RCB was statistically superior to M&P in both DFS (0.80 vs 0.68, p= 0.001) and OS (0.87 vs 0.69, p<0.001 ). This superiority value of RCB was consistent among all breast cancer subtypes. CONCLUSION: RCB index is as more accurated prognostic score to predict DFS and OS compared to M&P. Citation Format: Pons V, BurguÉs O, PÉrez-Fidalgo JA, MartÍnez MT, Pinilla K, Bermejo B, Lluch A. Validation of residual cancer burden index (RCB) as a prognostic tool in patients with early breast cancer (EBC) treated with neoadjuvant chemotherapy (NAC): Comparison of RCB and Miller & Payne system (M&P). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-14-12.

Abstract P6-08-39: Influence of lifestyle factors and tumor cell dissemination in 632 early breast cancer patients

Abstract Introduction: Influence of lifestyle behaviour in risk of developing breast cancer is supported by several lines. Data from 632 early breast cancer (EBC) patients were collected to evaluate the influence of lifestyle factors in progression free survival (PFS) and overall survival (OS). Results of disseminated tumor cell (DTC) in bone marrow and circulating tumor cells (CTC) in blood were available as well. A complete pathological data set and medical history were obtained. It was the purpose of the present study to correlate these data to compare the findings. Methods: We evaluated 629 bone marrow samples and 606 blood samples from EBC patients treatet between 2004 to 2010 at the time of first diagnosis. All samples underwent immunomagnetic enrichment using the AdnaTest BreastCancerSelect (AdnaGen AG, Germany) within 4 hours after blood withdrawal followed by RNA isolation and subsequent gene expression analysis by reverse transcription and Multiplex-PCR in separated tumor cells using the AdnaTest BreastCancerDetect. CTCs were analyzed for the three breast cancer associated markers: GA733-2, Muc-1, Her-2 and actin as an internal PCR control. BM aspirates were analyzed for DTCs by immunocytochemistry using the pan-cytokeratin antibody A45-B/B3. Lifestyle data icluding menopausal status, BMI, usage of Metformin, hormone replacement drugs, beta blockers and Bisphosphonates were collected by accessing the patient files. Histological data of the primary tumor were available for each patient. Results: The overall detection rate for CTCs was 15.41% (88/571 patients) and for DTC was 38.5% (242/628 patients), respectively. The mean BMI of 428 patients was 26.4 in 81/574 premenopausal, 426/574 postmenopausal and 67/574 perimenopausal patients. Medical history of smoking (128/394 patients), using hormone replacement therapy (92/354 patients), alcohol consumption (68/378 patients), having allergies (188/419), using Metformin (22/389 patients), taking beta blockers (83/392 patients) and Bisphosphonates (201/526 patients) were compared to PFS and OS as well as the histological data of the primary tumor. Conclusion: Lifestyle factors seems to influence the outcome in our cohort of EBC patients as shown in previous studies. Final data and results regarding to tumor cell dissemination compared to lifestyle behaviour will be available for the SABCS 2014. Citation Format: Bahriye Aktas, Anna Frackenpohl, Siegfried Hauch, Johann Kraus, Hans Armin Kestler, Rainer Klaus Kimmig, Sabine Kasimir-Bauer. Influence of lifestyle factors and tumor cell dissemination in 632 early breast cancer patients [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-08-39.

The persistence of disseminated tumor cells after systemic therapy and their influence on prognosis in early breast cancer patients.

1030 Background: Detection of disseminated tumor cells (DTC) in the bone marrow (BM) of early breast cancer (EBC) patients before the administration of systemic therapy is associated with poor outcome. The aim of this study was to evaluate the impact of DTC on overall survival (OS) and disease free survival (DFS) in a large cohort of EBC patients after the administration of systemic therapy. Methods: EBC patients receiving systemic therapy (endocrine therapy and/or chemotherapy +/- HER2-directed treatment) either prior to surgery (neoadjuvant systemic therapy, NST) or after surgery (adjuvant systemic therapy, AST) at Tuebingen University Hospital, Germany between 01/2003 and 06/2012 were available for this analysis. BM aspirates were collected during surgery / one year after surgery in patients receiving NST / AST. DTC were identified by immunocytochemistry (pancytokeratin antibody A45/B3) and cytomorphology. Survival was analyzed using univariate (log-rank test) and multivariate analysis (cox regression). Results: DTC were detected in 201 of 608 (35%) patients. 175 of 419 (42%) patients treated with NST and 35 of 189 (19%) patients treated with AST were DTC-positive. Chemotherapy / endocrine therapy was administered prior to BM aspiration in 399 (96%) / 19 (5%) of the patients receiving NST and in 99 (52%) / 158 (84%) of the patients receiving AST. On univariate analysis, the detection of DTC was a significant predictor of poor DFS (HR: 2.27, 95% CI: 1.48 – 3.48, p<0.001) and poor OS (HR: 1.89, 95% CI: 1.19 – 3.00, p=0.007). On multivariate analysis (considering all clinicopathological factors and the DTC-status), independent factors for DFS were DTC-status (negative vs. positive), grading (G2-3 vs. G3), nodal-status (negative vs. positive), and the ER-status (negative vs. positive). Independent factors for OS were grading, PR-status (negative vs. positive) and nodal-status. Conclusions: The persistence of DTC in the BM of EBC patients after systemic treatment is a strong and independent marker of poor prognosis. Determination of the DTC-status is thus promising to monitor the effect of systemic therapy and to identify patients that are in need of additional adjuvant therapy.