De-Escalation Strategies in Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Early Breast Cancer (BC): Final Analysis of the West German Study Group Adjuvant Dynamic Marker-Adjusted Personalized Therapy Trial Optimizing Risk Assessment and Therapy Response Prediction in Early BC HER2- and Hormone Receptor-Positive Phase II Randomized Trial-Efficacy, Safety, and Predictive Markers for 12 Weeks of Neoadjuvant Trastuzumab Emtansine With or Without Endocrine Therapy (ET) Versus Trastuzumab Plus ET.

Purpose Human epidermal growth factor receptor 2 (HER2)-positive/hormone receptor (HR)-positive breast cancer is a distinct subgroup associated with lower chemotherapy sensitivity and slightly better outcome than HER2-positive/HR-negative disease. Little is known about the efficacy of the combination of endocrine therapy (ET) with trastuzumab or with the potent antibody-cytotoxic, anti-HER2 compound trastuzumab emtansine (T-DM1) with or without ET for this subgroup. The West German Study Group trial, ADAPT (Adjuvant Dynamic Marker-Adjusted Personalized Therapy Trial Optimizing Risk Assessment and Therapy Response Prediction in Early Breast Cancer) compares pathologic complete response (pCR) rates of T-DM1 versus trastuzumab with ET in early HER2-positive/HR-positive breast cancer. Patients and Methods In this prospective, neoadjuvant, phase II trial, 375 patients with early breast cancer with HER2-positive and HR-positive status (n = 463 screened) were randomly assigned to 12 weeks of T-DM1 with or without ET or to trastuzumab with ET. The primary end point was pCR (ypT0/is/ypN0). Early response was assessed in 3-week post-therapeutic core biopsies (proliferation decrease ≥ 30% Ki-67 or cellularity response). Secondary end points included safety and predictive impact of early response on pCR. Adjuvant therapy followed national standards. Results Baseline characteristics were well balanced among the arms. More than 90% of patients completed the therapy per protocol. pCR was observed in 41.0% of patients treated with T-DM1, 41.5% of patients treated with T-DM1 and ET, and 15.1% with trastuzumab and ET ( P < .001). Early responders (67% of patients with assessable response) achieved pCR in 35.7% compared with 19.8% in nonresponders (odds ratio, 2.2; 95% CI, 1.24 to 4.19). T-DM1 was associated with a significantly higher prevalence of grade 1 to 2 toxicities, especially thrombocytopenia, nausea, and elevation of liver enzymes. Overall toxicity was low; seventeen therapy-related severe adverse events (T-DM1 arms v trastuzumab plus ET; 5.3% v 3.1%, respectively) were reported. Conclusion The ADAPT HER2-positive/HR-positive trial demonstrates that neoadjuvant T-DM1 (with or without ET) given for only 12 weeks results in a clinically meaningful pCR rate. Thus, a substantial number of patients are spared the adverse effects of systemic chemotherapy.

Barrier protective use of skin care to prevent chemotherapy-induced cutaneous symptoms and to maintain quality of life in patients with breast cancer.

PURPOSE: Chemotherapy with anthracyclines, taxanes, or alkylating agents often causes cutaneous side effects. Nonspecific inhibition of the proliferative activity of keratinocytes has antidifferentiation effects that lead to defects in the barrier function and, thus, to dry, itchy, and irritable skin. These cutaneous symptoms reduce the quality of life of the patients considerably. Conditioning with topical application of niacinamide uses the cytoprotective and barrier stabilizing effect of vitamin B3. PATIENTS AND METHODS: A multicenter randomized crossover study investigated the influence of the test preparation on the quality of life compared to standard care for 73 patients with breast cancer undergoing adjuvant or neoadjuvant cytostatic therapy. Primary target parameter was the Dermatology Life Quality Index with its respective subscales after 6 weeks of a twice-daily application of the respective preparations. Additionally, specific symptoms such as pruritus, dryness, and irritability have been assessed using visual analog scales. RESULTS: Regarding the total score of the Dermatology Life Quality Index, no relevant differences could be observed. However, the results for the "symptoms and feelings" subscale show a significant advantage in favor of the test preparation. Significant superiority of the test preparation could also be observed in the secondary target parameters, the visual analog scales (P<0.05). CONCLUSION: The results show for the first time a significant superiority of prophylactic application of niacinamide for maintaining quality of life while undergoing cytostatic treatment.

Analysis of PIK3CA mutations in breast cancer subtypes.

Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA) is a central element of a signaling pathway involved in cell proliferation, survival, and growth. Certain mutations in this pathway result in enhanced PI3K signaling, which is associated with oncogenic cellular transformation and cancer. The aims of this study were to characterize different types of PIK3CA mutations in exons 9 and 20 in a series of primary breast carcinomas and to correlate the results with clinicopathologic parameters and survival. We used frozen tissue samples and sequenced exons 9 and 20 for a series of 241 patients with a diagnosis of breast carcinoma. We found that 15.8% of the primary breast carcinomas possessed PIK3CA mutations in either exon 9 or exon 20. The rate of PIK3CA mutations was increased in HR(+)/HER2(-) tumors (18.6%), but this difference did not reach a statistical significance. The lowest rate of mutations was observed in HR(+)/HER2(+) tumors (5.3%). No statistically significant association was found between the presence of PIK3CA mutations and the prognostic/clinical features of breast cancer, including histologic subtype, Her2 status, axillary lymph node involvement, tumor grade, and tumor stage. However, the presence of the H1047R mutation in 10 samples was associated with a statistically significantly worse overall survival. PIK3CA mutation was found to be a frequent genetic change in all breast cancer subtypes but occurred with the highest rate in HR(+)/HER2(-) tumors. Further studies are needed to validate the prognostic impact of different PIK3CA mutations.

Comparative metabolomics of estrogen receptor positive and estrogen receptor negative breast cancer: alterations in glutamine and beta-alanine metabolism.

Molecular subtyping of breast cancer is necessary for therapy selection and mandatory for all breast cancer patients. Metabolic alterations are considered a hallmark of cancer and several metabolic drugs are currently being investigated in clinical trials. However, the dependence of metabolic alterations on breast cancer subtypes has not been investigated on -omics scale. Thus, 204 estrogen receptor positive (ER+) and 67 estrogen receptor negative (ER-) breast cancer tissues were investigated using GC-TOFMS based metabolomics. 19 metabolites were detected as altered in a predefined training set (2/3 of tumors) and could be validated in a predefined validation set (1/3 of tumors). The metabolite changes included increases in beta-alanine, 2-hydroyglutarate, glutamate, xanthine and decreases in glutamine in the ER- subtype. Beta-alanine demonstrated the strongest change between ER- and ER+ breast cancer (fold change=2.4, p=1.5E-20). In a correlation analysis with genome-wide expression data in a subcohort of 154 tumors, we found a strong negative correlation (Spearman R=-0.62) between beta-alanine and 4-aminobutyrate aminotransferase (ABAT). Immunohistological analysis confirmed down-regulation of the ABAT protein in ER- breast cancer. In a Kaplan-Meier analysis of a large external expression data set, the ABAT transcript was demonstrated to be a positive prognostic marker for breast cancer (HR=0.6, p=3.2E-15). BIOLOGICAL SIGNIFICANCE: It is well-known for more than a decade that breast cancer exhibits distinct gene expression patterns depending on the molecular subtype defined by estrogen receptor (ER) and HER2 status. Here, we show that breast cancer exhibits distinct metabolomics patterns depending on ER status. Our observation supports the current view of ER+ breast cancer and ER- breast as different diseases requiring different treatment strategies. Metabolic drugs for cancer including glutaminase inhibitors are currently under development and tested in clinical trials. We found glutamate enriched and glutamine reduced in ER- breast cancer compared to ER+ breast cancer and compared to normal breast tissues. Thus, metabolomics analysis highlights the ER- subtype as a preferential target for glutaminase inhibitors. For the first time, we report on a regulation of beta-alanine catabolism in cancer. In breast cancer, ABAT transcript expression was variable and correlated with ER status. Low ABAT transcript expression was associated with low ABAT protein expression and high beta-alanine concentration. In a large external microarray cohort, low ABAT expression shortened recurrence-free survival in breast cancer, ER+ breast cancer and ER- breast cancer.

Treatment of hepatic metastases of breast cancer with CT-guided interstitial brachytherapy - a phase II-study.

PURPOSE: The aim of the study was the evaluation of feasibility, safety and effectiveness of interstitial brachytherapy for the treatment of hepatic metastases of breast cancer. MATERIALS AND METHODS: Forty-one consecutive patients with 115 unresectable hepatic metastases of breast cancer were included in this phase-II-trial. They were treated in 69 interventions of CT-guided-interstitial-brachytherapy of the liver. Brachytherapy was applied as a single fraction high-dose-irradiation (15-25Gy (Gray)) using a (192)Ir-source of 10Ci. Nineteen patients presented systemically pretreated extrahepatic tumors. Primary endpoints were complications, local tumor control and progression-free survival. RESULTS: The median tumor diameter was 4.6 cm (1.5-11 cm). The median irradiation time per intervention was 26.5 min (range: 7-47 min). The applied median minimal dose at the CTV (clinical target volume) margin was 18.5 Gy (12-25 Gy). In 69 interventions and during the postinterventional period, one major complication (symptomatic post-interventional bleeding) (1.5%) and six minor complications occurred (8.7%). The median follow-up time was 18 months (range: 1-56). After 6, 12 and 18 months, local tumor control was 97%, 93.5% and 93.5%, intra- and extrahepatic progression free survival was 53%, 40% and 27%, and overall survival was 97%, 79% and 60%, respectively. CONCLUSION: CT-guided-brachytherapy is safe and effective for the treatment of liver metastases of breast cancer.

Phase II study of capecitabine plus trastuzumab in human epidermal growth factor receptor 2 overexpressing metastatic breast cancer pretreated with anthracyclines or taxanes.

PURPOSE: The oral fluoropyrimidine carbamate, capecitabine, is a highly active and well-tolerated treatment for metastatic breast cancer. In patients treated previously with anthracyclines and taxanes, capecitabine is an approved single-agent therapy. Trastuzumab, a monoclonal antibody targeting the human epidermal growth factor receptor 2 (HER-2), is also highly active in HER-2-overexpressing breast cancer. We have conducted a phase II study to confirm activity and feasibility of capecitabine and trastuzumab in combination in HER-2-overexpressing advanced/metastatic breast cancer. PATIENTS AND METHODS: Twenty-seven patients with HER-2-overexpressing metastatic breast cancer previously treated with anthracyclines and/or taxanes received oral capecitabine 1,250 mg/m(2) bid for 14 days followed by a 7-day rest period combined with intravenous trastuzumab 4 mg/kg body weight on day 1 (loading dose) followed by 2 mg/kg weekly. RESULTS: Capecitabine/trastuzumab treatment achieved objective responses in 12 patients (45%), including complete response in four patients (15%) and partial response in eight patients (30%). Disease was stabilized in an additional nine patients (33%). The median overall survival time was 28 months, and the median progression-free survival time was 6.7 months. The safety profile of the combination was favorable and predictable, with a low incidence of grade 3/4 adverse events. The most common adverse events were pain, hand-foot syndrome, and GI toxicities. Severe myelosuppression was rare and severe alopecia did not occur. CONCLUSION: These data confirm that the combination of capecitabine and trastuzumab is highly active in patients with HER-2-overexpressing anthracycline- and/or taxane-pretreated breast cancer, with only slight restrictions regarding quality of life.

Analysis of HER2 and HER4 in human myocardium to clarify the cardiotoxicity of trastuzumab (Herceptin).

PURPOSE: When combined with anthracyclines, the humanized anti-HER2 monoclonal antibody trastuzumab (Herceptin) provides significant clinical benefit for women with HER2-overexpressing metastatic breast cancer. However, its use is limited by severe cardiotoxicity. To clarify whether myocardial HER2 and HER4 expression in response to anthracycline exposure and cardiac damage contributes to cardiotoxicity, we assessed expression of HER2 and HER4 in pathologically altered myocardium. EXPERIMENTAL DESIGN: Cardiac biopsies from 60 patients with severe heart disease and cardiac tissue from 35 patients with breast cancer were obtained. Twenty-five of the patients with breast cancer had previously received anthracyclines. Three of 10 anthracycline-naïve patients with breast cancer had received trastuzumab. Expression of HER2 and HER4 was analyzed immunohistochemically (HER2: HercepTest/A0485 (Dako), Cy3 detection (Dianova); HER4: Ab-4 (NeoMarkers)). FISH analysis (Ventana) was used to assess HER2 gene amplification. RESULTS: Immunohistochemistry revealed weak HER2 membrane staining in six cardiac biopsies, appearing as dotted staining of the whole cell membrane and intensified HER2 signal using fluorescent Cy3 labeling. No HER2 membrane staining was detected in the remaining 54 cardiac biopsies or in the myocardium of the 35 patients with breast cancer. HER2 gene amplification was not observed. All specimens showed the mild cytoplasmatic HER4 staining of normal myocardium. No strong HER4 expression was detected. CONCLUSIONS: Cardiac alterations are not associated with an strong increase in HER2 and HER4 levels. IHC detects potential low-level HER2 expression in some samples. However, a more sensitive technique may be needed for studies of the role of HER2 in cardiac tissue. These data do not exclude a role for inhibition of cardiac HER2 expression by trastuzumab in the onset of heart failure in trastuzumab-treated patients.

The prognostic significance of epithelial-mesenchymal transition in breast cancer.

BACKGROUND: This study investigates the influence of epithelial-mesenchymal transition on prognosis in breast cancer. MATERIALS AND METHODS: Eighty breast carcinomas as well as 6 breast cancer cell lines were analysed immunohistochemically for the expression of epithelial keratins (K) K8, K19 and mesenchymal vimentin. Protein expression was correlated with histopathological factors and clinical follow-up. RESULTS: Suppression of K8 and K19 occurred in the majority of the tumours (72.5% and 65%), while aberrant expression of vimentin was found in 21.2% of the tumours. Suppression of K8 as well as expression of vimentin was significantly correlated with short survival (p < 0.004 and p < 0.006). Moreover HER2 overexpression significantly correlated with K19 (p < 0.0004) and vimentin (p < 0.0005). In cell lines with increasing invasive potential, epithelial keratins were lost in favour of mesenchymal vimentin. CONCLUSION: The transition from epithelial keratin to mesenchymal vimentin expression marks an important step in the malignant progression of breast cancer.