@article{BartmannFischerHuebneretal.2021, author = {Bartmann, Catharina and Fischer, Leah-Maria and H{\"u}bner, Theresa and M{\"u}ller-Reiter, Max and W{\"o}ckel, Achim and McNeill, Rhiannon V. and Schlaiss, Tanja and Kittel-Schneider, Sarah and K{\"a}mmerer, Ulrike and Diessner, Joachim}, title = {The effects of the COVID-19 pandemic on psychological stress in breast cancer patients}, series = {BMC Cancer}, volume = {21}, journal = {BMC Cancer}, doi = {10.1186/s12885-021-09012-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265802}, year = {2021}, abstract = {Background: The majority of breast cancer patients are severely psychologically affected by breast cancer diagnosis and subsequent therapeutic procedures. The COVID-19 pandemic and associated restrictions on public life have additionally caused significant psychological distress for much of the population. It is therefore plausible that breast cancer patients might be particularly susceptible to the additional psychological stress caused by the pandemic, increasing suffering. In this study we therefore aimed to assess the level of psychological distress currently experienced by a defined group of breast cancer patients in our breast cancer centre, compared to distress levels preCOVID-19 pandemic. Methods: Female breast cancer patients of all ages receiving either adjuvant, neoadjuvant, or palliative therapies were recruited for the study. All patients were screened for current or previous COVID-19 infection. The participants completed a self-designed COVID-19 pandemic questionnaire, the Stress and Coping Inventory (SCI), the National Comprehensive Cancer Network (R) (NCCN (R)) Distress Thermometer (DT), the European Organization for Research and Treatment of Cancer (EORTC) QLQ C30, and the BR23. Results: Eighty-two breast cancer patients were included. Therapy status and social demographic factors did not have a significant effect on the distress caused by the COVID-19 pandemic. The results of the DT pre and during COVID-19 pandemic did not differ significantly. Using the self-designed COVID-19 pandemic questionnaire, we detected three distinct subgroups demonstrating different levels of concerns in relation to SARS-CoV-2. The subgroup with the highest levels of concern reported significantly decreased life quality, related parameters and symptoms. Conclusions: This monocentric study demonstrated that the COVID-19 pandemic significantly affected psychological health in a subpopulation of breast cancer patients. The application of a self-created "COVID-19 pandemic questionnaire"could potentially be used to help identify breast cancer patients who are susceptible to increased psychological distress due to the COVID-19 pandemic, and therefore may need additional intensive psychological support.}, language = {en} } @article{BartmannJanakiRamanFloeteretal.2018, author = {Bartmann, Catharina and Janaki Raman, Sudha R. and Fl{\"o}ter, Jessica and Schulze, Almut and Bahlke, Katrin and Willingstorfer, Jana and Strunz, Maria and W{\"o}ckel, Achim and Klement, Rainer J. and Kapp, Michaela and Djuzenova, Cholpon S. and Otto, Christoph and K{\"a}mmerer, Ulrike}, title = {Beta-hydroxybutyrate (3-OHB) can influence the energetic phenotype of breast cancer cells, but does not impact their proliferation and the response to chemotherapy or radiation}, series = {Cancer \& Metabolism}, volume = {6}, journal = {Cancer \& Metabolism}, number = {8}, doi = {10.1186/s40170-018-0180-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-175607}, year = {2018}, abstract = {Background: Ketogenic diets (KDs) or short-term fasting are popular trends amongst supportive approaches for cancer patients. Beta-hydroxybutyrate (3-OHB) is the main physiological ketone body, whose concentration can reach plasma levels of 2-6 mM during KDs or fasting. The impact of 3-OHB on the biology of tumor cells described so far is contradictory. Therefore, we investigated the effect of a physiological concentration of 3 mM 3-OHB on metabolism, proliferation, and viability of breast cancer (BC) cells in vitro. Methods: Seven different human BC cell lines (BT20, BT474, HBL100, MCF-7, MDA-MB 231, MDA-MB 468, and T47D) were cultured in medium with 5 mM glucose in the presence of 3 mM 3-OHB at mild hypoxia (5\% oxygen) or normoxia (21\% oxygen). Metabolic profiling was performed by quantification of the turnover of glucose, lactate, and 3-OHB and by Seahorse metabolic flux analysis. Expression of key enzymes of ketolysis as well as the main monocarboxylic acid transporter MCT2 and the glucose-transporter GLUT1 was analyzed by RT-qPCR and Western blotting. The effect of 3-OHB on short- and long-term cell proliferation as well as chemo- and radiosensitivity were also analyzed. Results: 3-OHB significantly changed the oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in BT20 cells resulting in a more oxidative energetic phenotype. MCF-7 and MDA-MB 468 cells had increased ECAR only in response to 3-OHB, while the other three cell types remained uninfluenced. All cells expressed MCT2 and GLUT1, thus being able to uptake the metabolites. The consumption of 3-OHB was not strongly linked to mRNA overexpression of key enzymes of ketolysis and did not correlate with lactate production and glucose consumption. Neither 3-OHB nor acetoacetate did interfere with proliferation. Further, 3-OHB incubation did not modify the response of the tested BC cell lines to chemotherapy or radiation. Conclusions: We found that a physiological level of 3-OHB can change the energetic profile of some BC cell lines. However, 3-OHB failed to influence different biologic processes in these cells, e.g., cell proliferation and the response to common breast cancer chemotherapy and radiotherapy. Thus, we have no evidence that 3-OHB generally influences the biology of breast cancer cells in vitro.}, language = {en} } @article{WischnewskySchwentnerDiessneretal.2021, author = {Wischnewsky, Manfred and Schwentner, Lukas and Diessner, Joachim and De Gregorio, Amelie and Joukhadar, Ralf and Davut, Dayan and Salmen, Jessica and Bekes, Inga and Kiesel, Matthias and M{\"u}ller-Reiter, Max and Blettner, Maria and Wolters, Regine and Janni, Wolfgang and Kreienberg, Rolf and W{\"o}ckel, Achim and Ebner, Florian}, title = {BRENDA-Score, a hghly significant, internally and externally validated prognostic marker for metastatic recurrence: analysis of 10,449 primary breast cancer patients}, series = {Cancers}, volume = {13}, journal = {Cancers}, number = {13}, issn = {2072-6694}, doi = {10.3390/cancers13133121}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241064}, year = {2021}, abstract = {Background Current research in breast cancer focuses on individualization of local and systemic therapies with adequate escalation or de-escalation strategies. As a result, about two-thirds of breast cancer patients can be cured, but up to one-third eventually develop metastatic disease, which is considered incurable with currently available treatment options. This underscores the importance to develop a metastatic recurrence score to escalate or de-escalate treatment strategies. Patients and methods Data from 10,499 patients were available from 17 clinical cancer registries (BRENDA-project. In total, 8566 were used to develop the BRENDA-Index. This index was calculated from the regression coefficients of a Cox regression model for metastasis-free survival (MFS). Based on this index, patients were categorized into very high, high, intermediate, low, and very low risk groups forming the BRENDA-Score. Bootstrapping was used for internal validation and an independent dataset of 1883 patients for external validation. The predictive accuracy was checked by Harrell's c-index. In addition, the BRENDA-Score was analyzed as a marker for overall survival (OS) and compared to the Nottingham prognostic score (NPS). Results: Intrinsic subtypes, tumour size, grading, and nodal status were identified as statistically significant prognostic factors in the multivariate analysis. The five prognostic groups of the BRENDA-Score showed highly significant (p < 0.001) differences regarding MFS:low risk: hazard ratio (HR) = 2.4, 95\%CI (1.7-3.3); intermediate risk: HR = 5.0, 95\%CI.(3.6-6.9); high risk: HR = 10.3, 95\%CI (7.4-14.3) and very high risk: HR = 18.1, 95\%CI (13.2-24.9). The external validation showed congruent results. A multivariate Cox regression model for OS with BRENDA-Score and NPS as covariates showed that of these two scores only the BRENDA-Score is significant (BRENDA-Score p < 0.001; NPS p = 0.447). Therefore, the BRENDA-Score is also a good prognostic marker for OS. Conclusion: The BRENDA-Score is an internally and externally validated robust predictive tool for metastatic recurrence in breast cancer patients. It is based on routine parameters easily accessible in daily clinical care. In addition, the BRENDA-Score is a good prognostic marker for overall survival. Highlights: The BRENDA-Score is a highly significant predictive tool for metastatic recurrence of breast cancer patients. The BRENDA-Score is stable for at least the first five years after primary diagnosis, i.e., the sensitivities and specificities of this predicting system is rather similar to the NPI with AUCs between 0.76 and 0.81 the BRENDA-Score is a good prognostic marker for overall survival.}, language = {en} } @article{SteinWollschlaegerKreienbergetal.2016, author = {Stein, Roland Gregor and Wollschl{\"a}ger, Daniel and Kreienberg, Rolf and Janni, Wolfgang and Wischnewsky, Manfred and Diessner, Joachim and St{\"u}ber, Tanja and Bartmann, Catharina and Krockenberger, Mathias and Wischhusen, J{\"o}rg and W{\"o}ckel, Achim and Blettner, Maria and Schwentner, Lukas}, title = {The impact of breast cancer biological subtyping on tumor size assessment by ultrasound and mammography - a retrospective multicenter cohort study of 6543 primary breast cancer patients}, series = {BMC Cancer}, volume = {16}, journal = {BMC Cancer}, number = {549}, doi = {10.1186/s12885-016-2426-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161050}, year = {2016}, abstract = {Background Mammography and ultrasound are the gold standard imaging techniques for preoperative assessment and for monitoring the efficacy of neoadjuvant chemotherapy in breast cancer. Maximum accuracy in predicting pathological tumor size non-invasively is critical for individualized therapy and surgical planning. We therefore aimed to assess the accuracy of tumor size measurement by ultrasound and mammography in a multicentered health services research study. Methods We retrospectively analyzed data from 6543 patients with unifocal, unilateral primary breast cancer. The maximum tumor diameter was measured by ultrasound and/or mammographic imaging. All measurements were compared to final tumor diameter determined by postoperative histopathological examination. We compared the precision of each imaging method across different patient subgroups as well as the method-specific accuracy in each patient subgroup. Results Overall, the correlation with histology was 0.61 for mammography and 0.60 for ultrasound. Both correlations were higher in pT2 cancers than in pT1 and pT3. Ultrasound as well as mammography revealed a significantly higher correlation with histology in invasive ductal compared to lobular cancers (p < 0.01). For invasive lobular cancers, the mammography showed better correlation with histology than ultrasound (p = 0.01), whereas there was no such advantage for invasive ductal cancers. Ultrasound was significantly superior for HR negative cancers (p < 0.001). HER2/neu positive cancers were also more precisely assessed by ultrasound (p < 0.001). The size of HER2/neu negative cancers could be more accurately predicted by mammography (p < 0.001). Conclusion This multicentered health services research approach demonstrates that predicting tumor size by mammography and ultrasound provides accurate results. Biological tumor features do, however, affect the diagnostic precision.}, language = {en} } @article{DiessnerWischnewskyBlettneretal.2016, author = {Diessner, Joachim and Wischnewsky, Manfred and Blettner, Maria and H{\"a}usler, Sebastian and Janni, Wolfgang and Kreienberg, Rolf and Stein, Roland and St{\"u}ber, Tanja and Schwentner, Lukas and Bartmann, Catharina and W{\"o}ckel, Achim}, title = {Do Patients with Luminal A Breast Cancer Profit from Adjuvant Systemic Therapy? A Retrospective Multicenter Study}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {12}, doi = {10.1371/journal.pone.0168730}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-178217}, year = {2016}, abstract = {Background Luminal A breast cancers respond well to anti-hormonal therapy (HT), are associated with a generally favorable prognosis and constitute the majority of breast cancer subtypes. HT is the mainstay of treatment of these patients, accompanied by an acceptable profile of side effects, whereas the added benefit of chemotherapy (CHT), including anthracycline and taxane-based programs, is less clear-cut and has undergone a process of critical revision. Methods In the framework of the BRENDA collective, we analyzed the benefits of CHT compared to HT in 4570 luminal A patients (pts) with primary diagnosis between 2001 and 2008. The results were adjusted by nodal status, age, tumor size and grading. Results There has been a progressive reduction in the use of CHT in luminal A patients during the last decade. Neither univariate nor multivariate analyses showed any statistically significant differences in relapse free survival (RFS) with the addition of CHT to adjuvant HT, independent of the nodal status, age, tumor size or grading. Even for patients with more than 3 affected lymph nodes, there was no significant difference (univariate: p = 0.865; HR 0.94; 95\% CI: 0.46-1.93; multivariate: p = 0.812; HR 0.92; 95\% CI: 0.45-1.88). Conclusions The addition of CHT to HT provides minimal or no clinical benefit at all to patients with luminal A breast cancer, independent of the RFS-risk. Consequently, risk estimation cannot be the initial step in the decisional process. These findings-that are in line with several publications-should encourage the critical evaluation of applying adjuvant CHT to patients with luminal A breast cancer.}, language = {en} } @article{StanglRauchRauhetal.2021, author = {Stangl, Stephanie and Rauch, Sebastian and Rauh, J{\"u}rgen and Meyer, Martin and M{\"u}ller-Nordhorn, Jacqueline and Wildner, Manfred and W{\"o}ckel, Achim and Heuschmann, Peter U.}, title = {Disparities in Accessibility to Evidence-Based Breast Cancer Care Facilities by Rural and Urban Areas in Bavaria, Germany}, series = {Cancer}, volume = {127}, journal = {Cancer}, number = {13}, doi = {10.1002/cncr.33493}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239854}, pages = {2319 -- 2332}, year = {2021}, abstract = {Background Breast cancer (BC), which is most common in elderly women, requires a multidisciplinary and continuous approach to care. With demographic changes, the number of patients with chronic diseases such as BC will increase. This trend will especially hit rural areas, where the majority of the elderly live, in terms of comprehensive health care. Methods Accessibility to several cancer facilities in Bavaria, Germany, was analyzed with a geographic information system. Facilities were identified from the national BC guideline and from 31 participants in a proof-of-concept study from the Breast Cancer Care for Patients With Metastatic Disease registry. The timeframe for accessibility was defined as 30 or 60 minutes for all population points. The collection of address information was performed with different sources (eg, a physician registry). Routine data from the German Census 2011 and the population-based Cancer Registry of Bavaria were linked at the district level. Results Females from urban areas (n = 2,938,991 [ie, total of females living in urban areas]) had a higher chance for predefined accessibility to the majority of analyzed facilities in comparison with females from rural areas (n = 3,385,813 [ie, total number of females living in rural areas]) with an odds ratio (OR) of 9.0 for cancer information counselling, an OR of 17.2 for a university hospital, and an OR of 7.2 for a psycho-oncologist. For (inpatient) rehabilitation centers (OR, 0.2) and genetic counselling (OR, 0.3), women from urban areas had lower odds of accessibility within 30 or 60 minutes. Conclusions Disparities in accessibility between rural and urban areas exist in Bavaria. The identification of underserved areas can help to inform policymakers about disparities in comprehensive health care. Future strategies are needed to deliver high-quality health care to all inhabitants, regardless of residence.}, language = {en} } @article{DiessnerWischnewskyStueberetal.2016, author = {Diessner, Joachim and Wischnewsky, Manfred and St{\"u}ber, Tanja and Stein, Roland and Krockenberger, Mathias and H{\"a}usler, Sebastian and Janni, Wolfgang and Kreienberg, Rolf and Blettner, Maria and Schwentner, Lukas and W{\"o}ckel, Achim and Bartmann, Catharina}, title = {Evaluation of clinical parameters influencing the development of bone metastasis in breast cancer}, series = {BMC Cancer}, volume = {16}, journal = {BMC Cancer}, number = {307}, doi = {10.1186/s12885-016-2345-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161173}, year = {2016}, abstract = {Background The development of metastases is a negative prognostic parameter for the clinical outcome of breast cancer. Bone constitutes the first site of distant metastases for many affected women. The purpose of this retrospective multicentre study was to evaluate if and how different variables such as primary tumour stage, biological and histological subtype, age at primary diagnosis, tumour size, the number of affected lymph nodes as well as grading influence the development of bone-only metastases. Methods This retrospective German multicentre study is based on the BRENDA collective and included 9625 patients with primary breast cancer recruited from 1992 to 2008. In this analysis, we investigated a subgroup of 226 patients with bone-only metastases. Association between bone-only relapse and clinico-pathological risk factors was assessed in multivariate models using the tree-building algorithms "exhausted CHAID (Chi-square Automatic Interaction Detectors)" and CART(Classification and Regression Tree), as well as radial basis function networks (RBF-net), feedforward multilayer perceptron networks (MLP) and logistic regression. Results Multivariate analysis demonstrated that breast cancer subtypes have the strongest influence on the development of bone-only metastases (χ2 = 28). 29.9 \% of patients with luminal A or luminal B (ABC-patients) and 11.4 \% with triple negative BC (TNBC) or HER2-overexpressing tumours had bone-only metastases (p < 0.001). Five different mathematical models confirmed this correlation. The second important risk factor is the age at primary diagnosis. Moreover, BC subcategories influence the overall survival from date of metastatic disease of patients with bone-only metastases. Patients with bone-only metastases and TNBC (p < 0.001; HR = 7.47 (95 \% CI: 3.52-15.87) or HER2 overexpressing BC (p = 0.007; HR = 3.04 (95 \% CI: 1.36-6.80) have the worst outcome compared to patients with luminal A or luminal B tumours and bone-only metastases. Conclusion The bottom line of different mathematical models is the prior importance of subcategories of breast cancer and the age at primary diagnosis for the appearance of osseous metastases. The primary tumour stage, histological subtype, tumour size, the number of affected lymph nodes, grading and NPI seem to have only a minor influence on the development of bone-only metastases.}, language = {en} } @article{CurtazReifschlaegerStraehleetal.2022, author = {Curtaz, Carolin J. and Reifschl{\"a}ger, Leonie and Str{\"a}hle, Linus and Feldheim, Jonas and Feldheim, Julia J. and Schmitt, Constanze and Kiesel, Matthias and Herbert, Saskia-Laureen and W{\"o}ckel, Achim and Meybohm, Patrick and Burek, Malgorzata}, title = {Analysis of microRNAs in exosomes of breast cancer patients in search of molecular prognostic factors in brain metastases}, series = {International Journal of Molecular Sciences}, volume = {23}, journal = {International Journal of Molecular Sciences}, number = {7}, issn = {1422-0067}, doi = {10.3390/ijms23073683}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284476}, year = {2022}, abstract = {Brain metastases are the most severe tumorous spread during breast cancer disease. They are associated with a limited quality of life and a very poor overall survival. A subtype of extracellular vesicles, exosomes, are sequestered by all kinds of cells, including tumor cells, and play a role in cell-cell communication. Exosomes contain, among others, microRNAs (miRs). Exosomes can be taken up by other cells in the body, and their active molecules can affect the cellular process in target cells. Tumor-secreted exosomes can affect the integrity of the blood-brain barrier (BBB) and have an impact on brain metastases forming. Serum samples from healthy donors, breast cancer patients with primary tumors, or with brain, bone, or visceral metastases were used to isolate exosomes and exosomal miRs. Exosomes expressed exosomal markers CD63 and CD9, and their amount did not vary significantly between groups, as shown by Western blot and ELISA. The selected 48 miRs were detected using real-time PCR. Area under the receiver-operating characteristic curve (AUC) was used to evaluate the diagnostic accuracy. We identified two miRs with the potential to serve as prognostic markers for brain metastases. Hsa-miR-576-3p was significantly upregulated, and hsa-miR-130a-3p was significantly downregulated in exosomes from breast cancer patients with cerebral metastases with AUC: 0.705 and 0.699, respectively. Furthermore, correlation of miR levels with tumor markers revealed that hsa-miR-340-5p levels were significantly correlated with the percentage of Ki67-positive tumor cells, while hsa-miR-342-3p levels were inversely correlated with tumor staging. Analysis of the expression levels of miRs in serum exosomes from breast cancer patients has the potential to identify new, non-invasive, blood-borne prognostic molecular markers to predict the potential for brain metastasis in breast cancer. Additional functional analyzes and careful validation of the identified markers are required before their potential future diagnostic use.}, language = {en} } @article{CurtazKieselMeybohmetal.2022, author = {Curtaz, Carolin J. and Kiesel, Ludwig and Meybohm, Patrick and W{\"o}ckel, Achim and Burek, Malgorzata}, title = {Anti-hormonal therapy in breast cancer and its effect on the blood-brain barrier}, series = {Cancers}, volume = {14}, journal = {Cancers}, number = {20}, issn = {2072-6694}, doi = {10.3390/cancers14205132}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-290320}, year = {2022}, abstract = {Simple Summary Anti-hormonal therapie regimes are well established in oncological treatments in breast cancer. In contrast there is limited knowledge of their effects on metastatic brain metastases in advanced breast cancer and their ability to cross the blood brain-barrier. In this review, we point out the usual antihormonal therapy options in the primary disease, but also in metastatic breast cancer. In addition, we explain the epidemiological facts of brain metastases, as well as the basics of the blood-brain barrier and how this is overcome by metastase. Last but not least, we deal with the known anti-hormonal therapy options and present clinical studies on their intracerebral effect, as well as the known basics of their blood-brain barrier penetration. Not all common anti-hormonal therapeutics are able to penetrate the CNS. It is therefore important for the treating oncologists to use substances that have been proven to cross the BBB, despite the limited data available. Aromataseinhibitors, especially letrozole, probably also tamoxifen, everolimus and CDK4/6 inhibitors, especially abemaciclib, appear to act intracerebrally by overcoming the blood-brain barrier. Nevertheless, further data must be obtained in basic research, but also health care research in relation to patients with brain metastases. Abstract The molecular receptor status of breast cancer has implications for prognosis and long-term metastasis. Although metastatic luminal B-like, hormone-receptor-positive, HER2-negative, breast cancer causes brain metastases less frequently than other subtypes, though tumor metastases in the brain are increasingly being detected of this patient group. Despite the many years of tried and tested use of a wide variety of anti-hormonal therapeutic agents, there is insufficient data on their intracerebral effectiveness and their ability to cross the blood-brain barrier. In this review, we therefore summarize the current state of knowledge on anti-hormonal therapy and its intracerebral impact and effects on the blood-brain barrier in breast cancer.}, language = {en} } @article{LoebLinsmeierHerbertetal.2023, author = {L{\"o}b, Sanja and Linsmeier, Eva and Herbert, Saskia-Laureen and Schlaiß, Tanja and Kiesel, Matthias and Wischhusen, J{\"o}rg and Salmen, Jessica and Kranke, Peter and Quenzer, Anne and Kurz, Florian and Weiss, Claire and Gerhard-Hartmann, Elena and W{\"o}ckel, Achim and Diessner, Joachim}, title = {Prognostic effect of HER2 evolution from primary breast cancer to breast cancer metastases}, series = {Journal of Cancer Research and Clinical Oncology}, volume = {149}, journal = {Journal of Cancer Research and Clinical Oncology}, number = {8}, doi = {10.1007/s00432-022-04486-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324068}, pages = {5417-5428}, year = {2023}, abstract = {Purpose Therapeutic options for breast cancer (BC) treatment are constantly evolving. The Human Epidermal Growth Factor 2 (HER2)-low BC entity is a new subgroup, representing about 55\% of all BC patients. New antibody-drug conjugates demonstrated promising results for this BC subgroup. Currently, there is limited information about the conversion of HER2 subtypes between primary tumor and recurrent disease. Methods This retrospective study included women with BC at the University Medical Centre Wuerzburg from 1998 to 2021. Data were retrieved from patients' records. HER2 evolution from primary diagnosis to the first relapse and the development of secondary metastases was investigated. Results In the HR-positive subgroup without HER2 overexpression, HER2-low expression in primary BC was 56.7 vs. 14.6\% in the triple-negative subgroup (p < 0.000). In the cohort of the first relapse, HER2-low represented 64.1\% of HR-positive vs. 48.2\% of the triple-negative cohort (p = 0.03). In patients with secondary metastases, HER2-low was 75.6\% vs. 50\% in the triple negative subgroup (p = 0.10). The subgroup of HER2-positive breast cancer patients numerically increased in the course of disease; the HER2-negative overall cohort decreased. A loss of HER2 expression from primary BC to the first relapse correlated with a better OS (p = 0.018). No clinicopathological or therapeutic features could be identified as potential risk factors for HER2 conversion. Conclusion HER2 expression is rising during the progression of BC disease. In view of upcoming therapeutical options, the re-analysis of newly developed metastasis will become increasingly important.}, language = {en} }