Clinical and molecular characteristics of HER2-low-positive breast cancer: pooled analysis of individual patient data from four prospective, neoadjuvant clinical trials.

BACKGROUND: The development of anti-HER2 antibody-drug conjugates opens new therapeutic options for patients with breast cancer, including patients with low expression of HER2. To characterise this new breast cancer subtype, we have compared the clinical and molecular characteristics of HER2-low-positive and HER2-zero breast cancer, including response to neoadjuvant chemotherapy and prognosis. METHODS: In this pooled analysis of individual patient data, we evaluated a cohort of 2310 patients with HER2-non-amplified primary breast cancer that were treated with neoadjuvant combination chemotherapy in four prospective neoadjuvant clinical trials (GeparSepto, NCT01583426; GeparOcto, NCT02125344; GeparX, NCT02682693; Gain-2 neoadjuvant, NCT01690702) between July 30, 2012, and March 20, 2019. Central HER2 testing was done prospectively before random assignment of participants in all trials. HER2-low-positive status was defined as immunohistochemistry (IHC) 1+ or IHC2+/in-situ hybridisation negative and HER2-zero was defined as IHC0, based on the American Society of Clinical Oncology/College of American Pathologists guidelines. Disease-free survival and overall survival data were available for 1694 patients (from all trials except GeparX) with a median follow-up of 46·6 months (IQR 35·0-52·3). Bivariable and multivariable logistic regression models and Cox-proportional hazards models were performed based on a predefined statistical analysis plan for analysis of the endpoints pathological complete response, disease-free survival, and overall survival. FINDINGS: A total of 1098 (47·5%) of 2310 tumours were HER2-low-positive and 1212 (52·5%) were HER2-zero. 703 (64·0%) of 1098 patients with HER2-low-positive tumours were hormone receptor positive, compared with 445 (36·7%) of 1212 patients with HER2-zero tumours (p<0.0001). HER2-low-positive tumours had a significantly lower pathological complete response rate than HER2-zero tumours (321 [29·2%] of 1098 vs 473 [39·0%] of 1212, p=0·0002). Pathological complete response was also significantly lower in HER2-low-positive tumours versus HER2-zero tumours in the hormone receptor-positive subgroup (123 [17·5%] of 703 vs 105 [23·6%] of 445, p=0·024), but not in the hormone receptor-negative subgroup (198 [50·1%] of 395 vs 368 [48·0%] of 767, p=0·21). Patients with HER2-low-positive tumours had significantly longer survival than did patients with HER2-zero tumours (3-year disease-free survival: 83·4% [95% CI 80·5-85·9] vs 76·1% [72·9-79·0]; stratified log-rank test p=0·0084; 3-year overall survival: 91·6% [84·9-93·4] vs 85·8% [83·0-88·1]; stratified log-rank test p=0·0016). Survival differences were also seen in patients with hormone receptor-negative tumours (3-year disease-free survival: 84·5% [95% CI 79·5-88·3] vs 74·4% [70·2-78.0]; stratified log-rank test p=0·0076; 3-year overall survival: 90·2% [86·0-93·2] vs 84·3% [80·7-87·3], stratified log-rank test p=0·016), but not in patients with hormone receptor-positive tumours (3-year disease-free survival 82·8% [79·1-85·9] vs 79·3% [73·9-83·7]; stratified log-rank test p=0·39; 3-year overall survival 92·3% [89·6-94·4] vs 88·4% [83·8-91·8]; stratified log-rank test p=0·13). INTERPRETATION: Our results show that HER2-low-positive tumours can be identified as new subgroup of breast cancer by standardised IHC, distinct from HER2-zero tumours. HER2-low-positive tumours have a specific biology and show differences in response to therapy and prognosis, which is particularly relevant in therapy-resistant, hormone receptor-negative tumours. Our results provide a basis for a better understanding of the biology of breast cancer subtypes and the refinement of future diagnostic and therapeutic strategies. FUNDING: German Cancer Aid (Deutsche Krebshilfe).

TGFB-induced factor homeobox 1 (TGIF) expression in breast cancer.

BACKGROUND: Breast cancer (BC) is the most frequent female cancer and preferentially metastasizes to bone. The transcription factor TGFB-induced factor homeobox 1 (TGIF) is involved in bone metabolism. However, it is not yet known whether TGIF is associated with BC bone metastasis or patient outcome and thus of potential interest. METHODS: TGIF expression was analyzed by immunohistochemistry in 1197 formalin-fixed, paraffin-embedded tissue samples from BC patients treated in the GAIN (German Adjuvant Intergroup Node-Positive) study with two adjuvant dose-dense schedules of chemotherapy with or without bisphosphonate ibandronate. TGIF expression was categorized into negative/low and moderate/strong staining. Endpoints were disease-free survival (DFS), overall survival (OS) and time to primary bone metastasis as first site of relapse (TTPBM). RESULTS: We found associations of higher TGIF protein expression with smaller tumor size (p = 0.015), well differentiated phenotype (p < 0.001) and estrogen receptor (ER)-positive BC (p < 0.001). Patients with higher TGIF expression levels showed a significantly longer disease-free (DFS: HR 0.75 [95%CI 0.59-0.95], log-rank p = 0.019) and overall survival (OS: HR 0.69 [95%CI 0.50-0.94], log-rank p = 0.019), but no association with TTPBM (HR 0.77 [95%CI 0.51-1.16]; p = 0.213). Univariate analysis in molecular subgroups emphasized that elevated TGIF expression was prognostic for both DFS and OS in ER-positive BC patients (DFS: HR 0.68 [95%CI 0.51-0.91]; log-rank p = 0.009, interaction p = 0.130; OS: HR 0.60 [95%CI 0.41-0.88], log-rank p = 0.008, interaction p = 0.107) and in the HER2-negative subgroup (DFS:HR 0.67 [95%CI 0.50-0.88], log-rank p = 0.004, interaction p = 0.034; OS: HR 0.57 [95%CI 0.40-0.81], log-rank p = 0.002, interaction p = 0.015). CONCLUSIONS: Our results suggest that moderate to high TGIF expression is a common feature of breast cancer cells and that this is not associated with bone metastases as first site of relapse. However, a reduced expression is linked to tumor progression, especially in HER2-negative breast cancer. TRIAL REGISTRATION: This clinical trial has been registered with ClinicalTrials.gov ; registration number: NCT00196872 .

Efficacy and safety of nab-paclitaxel 125 mg/m2 and nab-paclitaxel 150 mg/m2 compared to paclitaxel in early high-risk breast cancer. Results from the neoadjuvant randomized GeparSepto study (GBG 69).

PURPOSE: The GeparSepto study demonstrated that the use of nab-paclitaxel instead of paclitaxel prior to anthracycline-based chemotherapy could lead to a significantly increased pCR rate, especially in the triple negative subpopulation. We report efficacy and safety for patients treated with two different doses of nab-paclitaxel in comparison to weekly solvent-formulated paclitaxel. METHODS: Patients were treated for 12 weeks with either intravenous nab-paclitaxel 150 mg/m2 (nP150) weekly, after study amendment 125 mg/m2 (nP125) weekly or solvent-based paclitaxel 80 mg/m2 (P80) weekly followed by epirubicin 90 mg/m2 and cyclophosphamide 600 mg/m2 on day 1 for four 3-week cycles. RESULTS: 229 patients received nP150, 377 nP125. Baseline characteristics were fairly balanced between these two sequential cohorts as well as compared to 601 patients receiving P80 except for hormone receptor status, HER2 status, and Ki67. Taxane treatment was discontinued in 26.8% (nP150), 16.6% (nP125), and 13.3% of (P80) patients, respectively. Median relative total dose intensity (mRTDI) based on 125 mg/m2 for nP was 103% with nP150, 95% with nP125, 99% with P80 before and 98% with P80 after the amendment. PSN grade 3-4 was observed in 14.5% of patients with nP150, 8.1% of patients with nP125 (p = 0.018), and 2.7% of patients with P80. Overall pCR before the amendment was 33.6% after nP150 and 23.5% after P80 (OR 1.65 [95% CI 1.10-2.50]; p = 0.022); pCR after the amendment was 41.4% after nP125, and 32.4% after P80 (1.48 [95% CI 1.10-1.99]; p = 0.013). CONCLUSIONS: Nab-paclitaxel 125 mg/m2 was associated with a better safety profile and compliance without compromising the efficacy compared to nab-paclitaxel 150 mg/m2.

Effect of Tailored Dose-Dense Chemotherapy vs Standard 3-Weekly Adjuvant Chemotherapy on Recurrence-Free Survival Among Women With High-Risk Early Breast Cancer: A Randomized Clinical Trial.

Importance: Standard dosing of chemotherapy based on body surface area results in marked interpatient variation in pharmacokinetics, toxic effects, and efficacy. Whether tailored dosing can improve outcomes is unknown, as is the role of dose-dense adjuvant chemotherapy. Objective: To determine whether tailored dose-dense adjuvant chemotherapy improves the outcomes of early breast cancer compared with a standard 3-weekly chemotherapy schedule. Design, Setting, and Participants: A randomized, open-label, phase 3 trial of women aged 65 years and younger who had surgery for nonmetastatic node-positive or high-risk node-negative breast cancer at 86 sites in Sweden, Germany, and Austria between February 20, 2007, and September 14, 2011. Interventions: Patients were randomized 1:1 either to 4 cycles of leukocyte nadir-based tailored and dose-dense adjuvant epirubicin and cyclophosphamide every 2 weeks followed by 4 cycles of tailored dose-dense docetaxel every 2 weeks, or to standard-interval chemotherapy with 3 cycles of fluorouracil and epirubicin-cyclophosphamide every 3 weeks followed by 3 cycles of docetaxel every 3 weeks. Main Outcomes and Measures: The primary end point was breast cancer recurrence-free survival (BCRFS). Secondary end points included 5-year event-free survival (EFS), distant disease-free survival (DDFS), overall survival (OS), and rates of grade 3 or 4 toxic effects. Results: Among 2017 randomized patients (1006 in the tailored dose-dense group and 1011 in the control group; median [IQR] age, 51 [45-58] years; 80% with hormone receptor-positive tumors; 97% with node-positive disease), 2000 received study treatment (≥1 cycle of chemotherapy; 1001 in the tailored dose-dense group and 999 in the control group). After a median follow-up of 5.3 years (IQR, 4.5-6.1 years), 269 BCRFS events were reported, 118 in the tailored dose-dense group and 151 in the control group (HR, 0.79; 95% CI, 0.61-1.01; log-rank P = .06; 5-year BCRFS, 88.7% vs 85.0%). The tailored dose-dense group had significantly better EFS than the control group (HR, 0.79; 95% CI, 0.63-0.99; P = .04; 5-year EFS, 86.7% vs 82.1%). The groups did not differ in OS (HR, 0.77; 95% CI, 0.57-1.05; P = .09; 5-year OS, 92.1% vs 90.2%) or DDFS (HR, 0.83; 95% CI, 0.64-1.08; P = .17; 5-year DDFS, 89.4% vs 86.7%). Grade 3 or 4 nonhematologic toxic effects occurred in 527 (52.6%) in the tailored dose-dense group and 366 (36.6%) in the control group. Conclusions and Relevance: Among women with high-risk early breast cancer, the use of tailored dose-dense chemotherapy compared with standard adjuvant chemotherapy did not result in a statistically significant improvement in breast cancer recurrence-free survival. Nonhematologic toxic effects were more frequent in the tailored dose-dense group. Trial Registration: clinicaltrials.gov Identifier: NCT00798070; isrctn.org Identifier: ISRCTN39017665.

Sentinel-lymph-node biopsy in patients with breast cancer before and after neoadjuvant chemotherapy (SENTINA): a prospective, multicentre cohort study.

BACKGROUND: The optimum timing of sentinel-lymph-node biopsy for breast cancer patients treated with neoadjuvant chemotherapy is uncertain. The SENTINA (SENTinel NeoAdjuvant) study was designed to evaluate a specific algorithm for timing of a standardised sentinel-lymph-node biopsy procedure in patients who undergo neoadjuvant chemotherapy. METHODS: SENTINA is a four-arm, prospective, multicentre cohort study undertaken at 103 institutions in Germany and Austria. Women with breast cancer who were scheduled for neoadjuvant chemotherapy were enrolled into the study. Patients with clinically node-negative disease (cN0) underwent sentinel-lymph-node biopsy before neoadjuvant chemotherapy (arm A). If the sentinel node was positive (pN1), a second sentinel-lymph-node biopsy procedure was done after neoadjuvant chemotherapy (arm B). Women with clinically node-positive disease (cN+) received neoadjuvant chemotherapy. Those who converted to clinically node-negative disease after chemotherapy (ycN0; arm C) were treated with sentinel-lymph-node biopsy and axillary dissection. Only patients whose clinical nodal status remained positive (ycN1) underwent axillary dissection without sentinel-lymph-node biopsy (arm D). The primary endpoint was accuracy (false-negative rate) of sentinel-lymph-node biopsy after neoadjuvant chemotherapy for patients who converted from cN1 to ycN0 disease during neoadjuvant chemotherapy (arm C). Secondary endpoints included comparison of the detection rate of sentinel-lymph-node biopsy before and after neoadjuvant chemotherapy, and also the false-negative rate and detection rate of sentinel-lymph-node biopsy after removal of the sentinel lymph node. Analyses were done according to treatment received (per protocol). FINDINGS: Of 1737 patients who received treatment, 1022 women underwent sentinel-lymph-node biopsy before neoadjuvant chemotherapy (arms A and B), with a detection rate of 99.1% (95% CI 98.3-99.6; 1013 of 1022). In patients who converted after neoadjuvant chemotherapy from cN+ to ycN0 (arm C), the detection rate was 80.1% (95% CI 76.6-83.2; 474 of 592) and false-negative rate was 14.2% (95% CI 9.9-19.4; 32 of 226). The false-negative rate was 24.3% (17 of 70) for women who had one node removed and 18.5% (10 of 54) for those who had two sentinel nodes removed (arm C). In patients who had a second sentinel-lymph-node biopsy procedure after neoadjuvant chemotherapy (arm B), the detection rate was 60.8% (95% CI 55.6-65.9; 219 of 360) and the false-negative rate was 51.6% (95% CI 38.7-64.2; 33 of 64). INTERPRETATION: Sentinel-lymph-node biopsy is a reliable diagnostic method before neoadjuvant chemotherapy. After systemic treatment or early sentinel-lymph-node biopsy, the procedure has a lower detection rate and a higher false-negative rate compared with sentinel-lymph-node biopsy done before neoadjuvant chemotherapy. These limitations should be considered if biopsy is planned after neoadjuvant chemotherapy. FUNDING: Brustkrebs Deutschland, German Society for Senology, German Breast Group.

Long-term Follow-up and Safety of Patients after an Upfront Therapy with Letrozole for Early Breast Cancer in Routine Clinical Care - The PreFace Study.

Introduction: Adjuvant treatment of patients with early-stage breast cancer (BC) should include an aromatase inhibitor (AI). Especially patients with a high recurrence risk might benefit from an upfront therapy with an AI for a minimum of five years. Nevertheless, not much is known about the patient selection for this population in clinical practice. Therefore, this study analyzed the prognosis and patient characteristics of postmenopausal patients selected for a five-year upfront letrozole therapy. Patients and Methods: From 2009 to 2011, 3529 patients were enrolled into the adjuvant phase IV PreFace clinical trial (NCT01908556). Postmenopausal hormone receptor-positive BC patients, for whom an upfront five-year therapy with letrozole (2.5 mg/day) was indicated, were eligible. Disease-free survival (DFS), overall survival (OS) and safety in relation to patient and tumor characteristics were assessed. Results: 3297 patients started letrozole therapy. The majority of patients (n = 1639, 57%) completed the five-year treatment. 34.5% of patients continued with endocrine therapy after the mandated five-year endocrine treatment. Five-year DFS rates were 89% (95% CI: 88-90%) and five-year OS rates were 95% (95% CI: 94-96%). In subgroup analyses, DFS rates were 83%, 84% and 78% for patients with node-positive disease, G3 tumor grading, and pT3 tumors respectively. The main adverse events (any grade) were pain and hot flushes (66.8% and 18.3% of patients). Conclusions: The risk profile of postmenopausal BC patients selected for a five-year upfront letrozole therapy showed a moderate recurrence and death risk. However, in subgroups with unfavorable risk factors, prognosis warrants an improvement, which might be achieved with novel targeted therapies.

Correction: Long-term Follow-up and Safety of Patients after an Upfront Therapy with Letrozole for Early Breast Cancer in Routine Clinical Care - The PreFace Study.

[This corrects the article DOI: 10.1055/a-2238-3153.].

Adjuvant capecitabine versus nihil in older patients with node-positive/high-risk node-negative early breast cancer receiving ibandronate - The ICE randomized clinical trial.

AIM OF THE STUDY: Evaluation of the impact of a de-escaleted chemotherapy regimen consisting of capecitabine (Cap) on invasive disease-free survival (iDFS) in patients ≥65 years with node-positive/high-risk node-negative early breast cancer (BC) receiving ibandronate (Ib). METHODS: ICE (Ib with or without Cap in Elderly patients with early breast cancer) was a multicentre phase 3 clinical trial with a 2020 update of long-term follow-up for overall survival enroling node-positive/high-risk node-negative patients ≥65 years with early BC. Patients were randomised to Cap 2000 mg/m² day 1-14 q3w for 6 cycles plus Ib (50 mg p.o. daily or alternatively 6 mg intravenous q4w) or Ib alone for 2 years. Endocrine therapy was recommended for hormone receptor (HR)-positive patients. The primary endpoint was iDFS analysed using Cox proportional hazards regression and log-rank analysis. RESULTS: 1358 (96.4%) of 1409 randomised patients started treatment. 564 (83.4%) completed 6 cycles of Cap. 513 (77.7%) and 516 (78.8%) completed Ib in the Cap+Ib and Ib alone arm, respectively. Median age was 71 (range 64-88) years, 1099 (81%) were HR-positive, 705 (51.9%) node-negative. At a median follow-up of 61.3 months, 5-year iDFS was 78.8% for Cap+Ib versus 75.0% for Ib alone (p = 0.80). Effects were independent of age, nodal, and HR status. The addition of Cap caused significantly higher skin and gastrointestinal toxicity. CONCLUSIONS: The adjuvant combination of Cap+Ib did not show significantly better iDFS than Ib alone in node-positive/high-risk node-negative older BC patients, of whom HR-positive patients were also treated with endocrine therapy. TRIAL REGISTRATION: Study in elderly patients with early breast cancer (ICE), NCT00196859, https://clinicaltrials.gov/ct2/show/NCT00196859?term=NCT00196859.

Caveolin Gene Expression Predicts Clinical Outcomes for Early-Stage HER2-Negative Breast Cancer Treated with Paclitaxel-Based Chemotherapy in the GeparSepto Trial.

PURPOSE: Caveolin-1 and -2 (CAV1/2) dysregulation are implicated in driving cancer progression and may predict response to nab-paclitaxel. We explored the prognostic and predictive potential of CAV1/2 expression for patients with early-stage HER2-negative breast cancer receiving neoadjuvant paclitaxel-based chemotherapy regimens, followed by epirubicin and cyclophosphamide. EXPERIMENTAL DESIGN: We correlated tumor CAV1/2 RNA expression with pathologic complete response (pCR), disease-free survival (DFS), and overall survival (OS) in the GeparSepto trial, which randomized patients to neoadjuvant paclitaxel- versus nab-paclitaxel-based chemotherapy. RESULTS: RNA sequencing data were available for 279 patients, of which 74 (26.5%) were hormone receptor (HR)-negative, thus triple-negative breast cancer (TNBC). Patients treated with nab-paclitaxel with high CAV1/2 had higher probability of obtaining a pCR [CAV1 OR, 4.92; 95% confidence interval (CI), 1.70-14.22; P = 0.003; CAV2 OR, 5.39; 95% CI, 1.76-16.47; P = 0.003] as compared with patients with high CAV1/2 treated with solvent-based paclitaxel (CAV1 OR, 0.33; 95% CI, 0.11-0.95; P = 0.040; CAV2 OR, 0.37; 95% CI, 0.12-1.13; P = 0.082). High CAV1 expression was significantly associated with worse DFS and OS in paclitaxel-treated patients (DFS HR, 2.29; 95% CI, 1.08-4.87; P = 0.030; OS HR, 4.97; 95% CI, 1.73-14.31; P = 0.003). High CAV2 was associated with worse DFS and OS in all patients (DFS HR, 2.12; 95% CI, 1.23-3.63; P = 0.006; OS HR, 2.51; 95% CI, 1.22-5.17; P = 0.013), in paclitaxel-treated patients (DFS HR, 2.47; 95% CI, 1.12-5.43; P = 0.025; OS HR, 4.24; 95% CI, 1.48-12.09; P = 0.007) and in patients with TNBC (DFS HR, 4.68; 95% CI, 1.48-14.85; P = 0.009; OS HR, 10.43; 95% CI, 1.22-89.28; P = 0.032). CONCLUSIONS: Our findings indicate high CAV1/2 expression is associated with worse DFS and OS in paclitaxel-treated patients. Conversely, in nab-paclitaxel-treated patients, high CAV1/2 expression is associated with increased pCR and no significant detriment to DFS or OS compared with low CAV1/2 expression.

Inferred Immune-Cell Activity Is an Independent Predictor of HER2-Negative Breast Cancer Prognosis and Response to Paclitaxel-Based Therapy in the GeparSepto Trial.

PURPOSE: Tumor microenvironment (TME) immune markers have been correlated with both response to neoadjuvant therapy and prognosis in patients with breast cancer. Here, immune-cell activity of breast cancer tumors was inferred by expression-based analysis to determine if it is prognostic and/or predictive of response to neoadjuvant paclitaxel-based therapy in the GeparSepto (G7) trial (NCT01583426). EXPERIMENTAL DESIGN: Pre-study biopsies from 279 patients with HER2-negative breast cancer in the G7 trial underwent RNA-seq-based profiling of 104 immune-cell-specific genes to assess inferred Immune Cell Activity (iICA) of 23 immune-cell types. Hierarchical clustering was used to classify tumors as iICA "hot," "warm," or "cold" by comparison of iICA in the G7 cohort relative to that of 1,467 samples from a tumor database established by Nantomics LLC. Correlations between iICA cluster, pathology-assessed tumor-infiltrating lymphocytes (TIL), and hormone receptor (HR) status for pathologic complete response (pCR), disease-free survival (DFS), and overall survival (OS) were determined. RESULTS: iICA cluster correlated with TIL levels. The highest pCR rates were observed in hot cluster tumors, and those with relatively higher TILs. Greater inferred activity of several T-cell types was significantly associated with pCR and survival. DFS and OS were prolonged in patients with hot or warm cluster tumors, the latter particularly for HR negative tumors, even if TILs were relatively low. CONCLUSIONS: Overall, TIL level better predicted pCR, but iICA cluster better predicted survival. Differences in associations between TILs, cluster, pCR, and survival were observed for HR-positive tumors versus HR-negative tumors, suggesting expanded study of the implication of these findings is warranted.

Outcome of breast cancer patients treated with chemotherapy during pregnancy compared with non-pregnant controls.

BACKGROUND: A diagnosis of breast cancer during pregnancy (PrBC) does not impact prognosis if standard treatment is offered. However, caution is warranted as gestational changes in pharmacokinetics may lead to reduced chemotherapy concentration. METHODS: Survival of PrBC patients treated with chemotherapy during pregnancy was compared to non-pregnant breast cancer patients treated with chemotherapy, diagnosed after 2000, excluding patients older than 45 years or with a postpartum diagnosis. The data was registered in two multicenter registries (the International Network of Cancer, Infertility and Pregnancy and the German Breast Group). Cox proportional hazards regression was used to compare disease-free (DFS) and overall survival (OS) between both groups, adjusting for age, stage, grade, hormone receptor status, human epidermal growth factor 2 status and histology, weighted by propensity scoring to account for the differences in baseline characteristics between pregnant patients and controls. RESULTS: In total, 662 pregnant and 2081 non-pregnant patients were selected. Pregnant patients were more likely to have stage II breast cancer (60.1% vs 56.1%, p = 0.035), grade 3 tumors (74.0% vs 62.2%, p < 0.001), hormone receptor-negative tumors (48.4% vs 34.0%, p < 0.001) or triple-negative breast cancer (38.9% vs 26.9%, p < 0.001). Median follow-up was 66 months. In multivariable analysis, DFS and OS were comparable for pregnant and non-pregnant patients (DFS: HR 1.02, 95% CI 0.82-1.27, p = 0.83; OS: HR 1.08, 95% CI 0.81-1.45, p = 0.59). CONCLUSION: Outcome of women with breast cancer treated with chemotherapy during pregnancy is comparable to young non-pregnant women. These results support chemotherapy for PrBC when indicated.

Subcutaneous injection of trastuzumab into the thigh versus abdominal wall in patients with HER2-positive early breast cancer: Pharmacokinetic, safety and patients' preference - Substudy of the randomised phase III GAIN-2 study.

BACKGROUND: Trastuzumab given intravenously in combination with chemotherapy is standard of care for patients with early HER2-positive breast cancer (BC). Different randomised studies have shown equivalent efficacy of a subcutaneous injection into the thigh compared to the intravenous formulation. Other body regions for injection have not been investigated but might be more convenient for patients. METHODS: After surgery, patients were randomised to receive either subcutaneous trastuzumab into the thigh or into the abdominal wall (AW). Patient preferences were evaluated using validated questionnaires (PINT). Primary objectives of this multicentre, non-blinded, randomised substudy of the GAIN-2 study were to investigate pharmacokinetics of the injection into the thigh versus AW and to determine patients' preferences of either administration site versus the previously received intravenous application. RESULTS: 226 patients were randomised and 219 patients (thigh: N = 110; AW: N = 109) formed the modified intent-to-treat (mITT). Overall, 83.5% (out of N = 182 with information about patients' preference) preferred subcutaneous over previous intravenous application or had no preference. Preference was similar between both administration sites (thigh: 80.6%; AW: 86.5; p = 0.322). Pharmacokinetic analysis included 30 patients. Geometric means of Cmax and AUC0-21d were higher in thigh than in AW group (geometric mean ratio with body weight adjustment: Cmax: 1.291, 90%-CI 1.052-1.584; AUC0-21d: 1.291, 90%-CI 1.026-1.626). Safety profile was in line with previous reports of subcutaneous trastuzumab. CONCLUSION: Subcutaneous trastuzumab into the thigh showed an approximately 30% higher bioavailability. Injections were well tolerated and preferred over intravenous administration. The subcutaneous injection into the thigh should remain the standard of care.

Neo-adjuvant and/or Adjuvant Subcutaneous Trastuzumab (Herceptin®) in Patients With Early HER2-positive Breast Cancer: Real World Data from a German Observational Study - (NIS HerSCin).

BACKGROUND/AIM: Subcutaneous Herceptin (HER SC) has been shown to be equally effective and safe compared to intravenous Herceptin (HER i.v.) application in early HER2-positive breast cancer (HER2+ BC). However, real-world data from the subcutaneous application are currently limited. PATIENTS AND METHODS: Based on a non-interventional study (NIS), data from routine clinical use of HER SC have been gathered between 2013 and 2018 in 135 hospitals and open-care practices throughout Germany. RESULTS: A total of 265 patients were recruited in the neo-adjuvant and 605 patients in the adjuvant setting. Primary effectiveness endpoint in the neoadjuvant treatment setting was pathological complete response rate, which was achieved in 41.5%. Primary endpoint in the adjuvant setting was disease free survival rate after 2 years (94.9%). Safety results from the study were comparable to the well-known safety profile of HER i.v. including preferred terms, incidence, severity, including cardiac events. No new safety signals were detected. CONCLUSION: Effectiveness and safety of HER SC were comparable to data from HER i.v. in early HER2+ BC.

Efficacy of Endocrine Therapy for the Treatment of Breast Cancer in Men: Results from the MALE Phase 2 Randomized Clinical Trial.

IMPORTANCE: The extent of changes in estradiol levels in male patients with hormone receptor-positive breast cancer receiving standard endocrine therapies is unknown. The sexual function and quality of life related to those changes have not been adequately evaluated. OBJECTIVE: To assess the changes in estradiol levels in male patients with breast cancer after 3 months of therapy. DESIGN, SETTING, AND PARTICIPANTS: This multicenter, phase 2 randomized clinical trial assessed 56 male patients with hormone receptor-positive breast cancer. Patients were recruited from 24 breast units across Germany between October 2012 and May 2017. The last patient completed 6 months of treatment in December 2017. The analysis data set was locked on August 24, 2018, and analysis was completed on December 19, 2018. INTERVENTIONS: Patients were randomized to 1 of 3 arms: tamoxifen alone or tamoxifen plus gonadotropin-releasing hormone analogue (GnRHa) or aromatase inhibitor (AI) plus GnRHa for 6 months. MAIN OUTCOMES AND MEASURES: The primary end point was the change in estradiol levels from baseline to 3 months. Secondary end points were changes of estradiol levels after 6 months, changes of additional hormonal parameters, adverse effects, sexual function, and quality of life after 3 and 6 months. RESULTS: In this phase 2 randomized clinical trial, a total of 52 of 56 male patients with a median (range) age of 61.5 (37-83) years started treatment. A total of 3 patients discontinued study treatment prematurely, 1 in each arm. A total of 50 patients were evaluable for the primary end point. After 3 months the patients' median estradiol levels increased by 67% (a change of +17.0 ng/L) with tamoxifen, decreased by 85% (-23.0 ng/L) with tamoxifen plus GnRHa, and decreased by 72% (-18.5 ng/L) with AI plus GnRHa (P < .001). After 6 months, median estradiol levels increased by 41% (a change of +12 ng/L) with tamoxifen, decreased by 61% (-19.5 ng/L) with tamoxifen plus GnRHa, and decreased by 64% (-17.0 ng/L) with AI plus GnRHa (P < .001). Sexual function and quality of life decreased when GnRHa was added but were unchanged with tamoxifen alone. CONCLUSIONS AND RELEVANCE: This phase 2 randomized clinical trial found that AI or tamoxifen plus GnRHa vs tamoxifen alone led to a sustained decrease of estradiol levels. The decreased hormonal parameters were associated with impaired sexual function and quality of life. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01638247.

Chemotherapy-induced ovarian failure in young women with early breast cancer: Prospective analysis of four randomised neoadjuvant/adjuvant breast cancer trials.

BACKGROUND: Young women receiving chemotherapy for early breast cancer (EBC) have a high probability for ovarian failure, defined by chemotherapy-induced amenorrhea (CIA) as a surrogate. CIA is insufficiently reliable and reproducible. We analysed chemotherapy-induced ovarian failure (CIOF) by assessing hormone parameters, CIA, and antral follicle count (AFC). METHODS: Blood samples of women aged ≤45 years treated with anthracycline/taxane-based chemotherapy for EBC from four neoadjuvant/adjuvant trials were collected at baseline, at the end of treatment (EOT), and at 6, 12, 18, and 24 months after EOT. Centrally assessed oestradiol (cutoff <52.2 ng/L) and follicle-stimulating hormone (cutoff >12.4IU/L) were used to define CIOF for patients with baseline premenopausal hormone levels, anti-Müllerian hormone (AMH), and AFC to assess ovarian reserve. Further analyses included CIA, regain of premenopausal hormone levels, and disease-free survival (DFS) also in subgroups. RESULTS: Six hundred ninety-six patients aged ≤45 years had premenopausal hormone levels at baseline. Overall, 85.1% (592/696) experienced CIOF at EOT, and 147 of 592 had further hormone measurements after EOT. Of those, 32.7% (48/147) regained premenopausal hormone levels after 6 months, 57.9% (66/114) regained premenopausal hormone levels after 12 months, 83.0% (73/88) regained premenopausal hormone levels after 18 months, and 89.2% (74/83) regained premenopausal hormone levels after 24 months. After 24 months, 72.4% (21/29) of patients without CIOF and 100% (14/14) with CIOF had low AMH levels. Four-year DFS without CIOF versus CIOF was 65.9% versus 84.6% (hazard ratio [HR] = 2.09, 95% confidence interval [CI]: 1.37-3.19; P < 0.001); in hormone receptor positive 61.8% versus 87.5% (HR = 2.69, 95% CI: 1.57-4.60; P < 0.001); in <30 years 68.3% versus 92.6% (HR = 4.87, 95% CI: 1.05-22.63; P = 0.026). CONCLUSION: Most premenopausal women experienced CIOF after chemotherapy for EBC. After 2 years, nearly all regain premenopausal hormone levels. CIOF was associated with better DFS, especially in patients with hormone receptor-positive EBC or aged <30 years.

Phase III randomised trial comparing intense dose-dense chemotherapy to tailored dose-dense chemotherapy in high-risk early breast cancer (GAIN-2).

BACKGROUND: The GAIN-2 trial was designed to identify a superior intense dose-dense (idd) strategy for high-risk patients with early breast cancer. Here, we report an interim analysis, at which the predefined futility boundary was crossed. PATIENTS AND METHODS: GAIN-2 was an open-label, randomised, multicentre phase III trial. Two thousand eight hundred and eighty seven patients were randomised 1:1 between three courses each of idd epirubicin (E) 150 mg/m2, nab-paclitaxel (nP) 330 mg/m2 and cyclophosphamide (C) 2000 mg/m2 (iddEnPC) versus four cycles of leucocyte nadir-based tailored and dose-dense EC (dtEC) followed by four cycles of tailored and dose-dense docetaxel (dtD) (dtEC-dtD). RESULTS: The duration of median follow-up was 45.8 (range 0.0-88.3) months. Trial objectives included invasive disease-free survival (iDFS) as the primary end-point. A total of 593 patients received the treatment as neoadjuvant chemotherapy. At the time of futility interim analysis, 414 events for iDFS were reported. Overall, there was no difference in iDFS between iddEnPC and dtEC-dtD with 4-year iDFS rates of 84.3% (95% confidence interval (CI) 82.0-86.4%). Among all predefined subgroups, hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2-), lobular cancer and ≤50 years subgroups predicted for better iDFS in the dtEC-dtD arm. Overall, 88.1% of patients completed all treatment in both arms. Haematological toxicity grade 3/4 and grade 3/4 non-haematological adverse events were significantly higher with iddEnPC (iddEnPC 50.8% vs dtEC-dtD 45.1%, P = 0.002), especially arthralgia and peripheral sensory neuropathy. Two treatment-related deaths occurred during dtEC-dtD, corresponding to a low mortality rate of 0.07%. CONCLUSIONS: iDFS is equal in both regimens, but tailoring dose-dense chemotherapy improved outcomes in HR+/HER2-, lobular cancer and patients ≤50 years.

Residual Axillary Burden After Neoadjuvant Chemotherapy (NACT) in Early Breast Cancer in Patients with a priori Clinically Occult Nodal Metastases - a transSENTINA Analysis.

Background Among patients with breast cancer undergoing neoadjuvant chemotherapy (NACT), the association between pathological complete remission (pCR) in the breast and clinical/pathological parameters is well established, whereas the association between these parameters and residual axillary involvement after NACT remains unclear. Methods Patients with clinically occult nodal metastases (i.e. negative by clinical assessment but positive by SLNB prior to NACT, i.e. Arm B of the SENTINA trial) were included in the presented analysis. All patients received a second sentinel lymph node biopsy (SLNB) and axillary dissection after NACT. Univariate and multivariate analyses were carried out to evaluate the association between clinical/pathological parameters and axillary involvement after NACT. Results Arm B of the SENTINA study contained 360 patients, 318 of which were evaluable for this analysis. After NACT, 71/318 (22.3%) patients had involved SLNs or non-SLNs after NACT. Overall, 71/318 (22.3%) patients achieved a pCR in the breast. Associations of extranodal spread, lack of multifocality and pCR in the breast with residual axillary burden were statistically significant. In a descriptive analysis including all patients with clinically negative axilla before NACT in the SENTINA trial 1.2% of triple negative (TN) patients and 0.5% of HER/2 positive patients had residual axillary disease in case of a breast pCR. Conclusions Patients in the SENTINA trial with clinically negative axilla and involved SLNs still carried a significant risk of nodal metastases after NACT. However, the risk of residual axillary burden was particularly low in TN and HER/2 positive tumors in case of a breast pCR.

Correction: Residual Axillary Burden After Neoadjuvant Chemotherapy (NACT) in Early Breast Cancer in Patients with a priori Clinically Occult Nodal Metastases - a transSENTINA Analysis.

[This corrects the article DOI: 10.1055/a-1298-3453.].

Relevance of tumour-infiltrating lymphocytes, PD-1 and PD-L1 in patients with high-risk, nodal-metastasised breast cancer of the German Adjuvant Intergroup Node-positive study.

BACKGROUND: Immune cell infiltration in breast cancer is important for the patient's prognosis and response to systemic therapies including immunotherapy. We sought to investigate the prevalence of tumour-infiltrating lymphocytes (TILs) and their association with immune checkpoints such as programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) in high-risk, node-positive breast cancer of the adjuvant German Adjuvant Intergroup Node-positive (GAIN-1) trial. PATIENTS AND METHODS: We evaluated TILs by haematoxylin and eosin staining and PD-1 and PD-L1 (SP263 assay) expression by immunohistochemistry in 1318 formalin-fixed, paraffin-embedded breast carcinomas. The association of TILs with PD-1, PD-L1, molecular intrinsic subtypes, outcome and therapy regimens (dose-dense [dd] epirubicin, paclitaxel and cyclophosphamide [EPC] and dd epirubicin, cyclophosphamide, paclitaxel and capecitabine [EC-PwX]) was statistically tested. RESULTS: Overall TILs density was significantly associated with the expression of PD-1 and PD-L1 in immune cells (each p < 0.0001) and PD-L1 in tumour cells (p = 0.0051). TILs were more common in triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2 (HER2)-positive tumours (each p < 0.0001). On multivariate Cox regression analyses, patients with breast cancer without TILs had an unfavourable disease-free survival (DFS) in the EPC arm compared with the EC-PwX arm (hazard ratio [HR] = 0.69 [0.44-1.06], p = 0.0915); but no differences were seen in tumours with TILs (HR = 1.24 [0.92-1.67], p = 0.1566, interaction p = 0.0336). PD-1-positive immune cells in TNBC were associated with a significantly better DFS (HR = 0.50 [0.25-0.99], p = 0.0457). PD-L1 expression had no impact on patient outcome. CONCLUSIONS: TILs predict the benefit of intensified ddEPC compared with ddEC-PwX therapy in node-positive, high-risk breast cancer. TILs, PD-1 and PD-L1 are linked to each other indicating tumour immunogenicity. Moreover, PD-1-positive immune cells have a positive prognostic impact in TNBC. CLINICAL TRIAL: NCT00196872.