Trastuzumab and first-line taxane chemotherapy in metastatic breast cancer patients with a HER2-negative tumor and HER2-positive circulating tumor cells: a phase II trial.

PURPOSE: HER2 overexpressing circulating tumor cells (CTCs) are observed in up to 25% of HER2-negative metastatic breast cancer patients. Since targeted anti-HER2 therapy has drastically improved clinical outcomes of patients with HER2-positive breast cancer, we hypothesized that patients with HER2 overexpressing CTCs might benefit from the addition of trastuzumab to chemotherapy. METHODS: In this single-arm, phase II trial, patients with HER2-positive CTCs received trastuzumab as addition to first-line treatment with taxane chemotherapy. Patients with detectable CTCs but without HER2 overexpression that received taxane chemotherapy only, were used as control group. The primary outcome measure was progression-free rate at 6 months (PFR6), with a target of 80%. In November 2022, the study was terminated early due to slow patient accrual. RESULTS: 63 patients were screened, of which eight patients had HER2-positive CTCs and were treated with trastuzumab. The median number of CTCs was 15 per 7.5 ml of blood (range 1-131) in patients with HER2-positive CTCs, compared to median 5 (range 1-1047) in the control group. PFR6 was 50% in the trastuzumab group and 54% in the taxane monotherapy group, with no significant difference in median PFS (8 versus 9 months, p = 0.51). CONCLUSION: No clinical benefit of trastuzumab was observed, although this study was performed in a limited number of patients. Additionally, we observed a strong correlation between the number of evaluable CTCs and the presence of HER2-positive CTCs. We argue that randomized studies investigating agents that are proven to be solely effective in the HER2-positive patient group in patients with HER2-positive CTCs and HER2-negative tissue are currently infeasible. Several factors contribute to this impracticality, including the need for more stringent thresholds, and the rapidly evolving landscape of cancer treatments.

The effect of (neo)adjuvant chemotherapy on long-term survival outcomes in patients with invasive lobular breast cancer treated with endocrine therapy: A retrospective cohort study.

BACKGROUND: Despite histological and molecular differences between invasive lobular carcinoma (ILC) and invasive carcinoma of no special type, according to national treatment guidelines no distinction is made regarding the use of (neo)adjuvant chemotherapy. Studies on the long-term outcome of chemotherapy in patients with ILC are scarce and show inconclusive results. METHODS: All patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative ILC with an indication for chemotherapy treated with adjuvant endocrine therapy were selected from the Erasmus Medical Center Breast Cancer database. Cox proportional hazards models were used to estimate the effect of chemotherapy on recurrence-free survival (RFS), breast cancer-specific survival (BCSS), and overall survival (OS). RESULTS: A total of 520 patients were selected, of whom 379 were treated with chemotherapy and 141 were not. Patients in the chemotherapy group were younger (51 vs. 61 years old; p < .001), had a higher T status (T3+, 33% vs. 14%; p < .001), and more often had lymph node involvement (80% vs. 49%; p < .001) in comparison to the no-chemotherapy group. After adjusting for confounders, chemotherapy treatment was not associated with better RFS (hazard ratio [HR], 1.20; 95% confidence interval [CI], 0.63-2.31), BCSS (HR, 1.24; 95% CI, 0.60-2.58), or OS (HR, 0.97; 95% CI, 0.56-1.66). This was also reflected by adjusted Cox survival curves in the chemotherapy versus no-chemotherapy group for RFS (75% vs. 79%), BCSS (80% vs. 84%), and OS (72% vs. 71%). CONCLUSIONS: Chemotherapy is not associated with improved RFS, BCSS, or OS for patients with ER+/HER2- ILC treated with adjuvant endocrine therapy and with an indication for chemotherapy.

Tumor-agnostic ctDNA levels by mFAST-SeqS in first-line HR-positive, HER2 negative metastatic breast cancer patients as a biomarker for survival.

This prospective cohort study reports aneuploidy score by mFast-SeqS as a strong prognostic marker in MBC patients. mFAST-SeqS is an affordable and easily implementable method for the assessment of total ctDNA levels and, as such, provides an alternative prognostic tool. One mixed cohort (cohort A, n = 45) starting any type of treatment in any line of therapy and one larger cohort (cohort B, n = 129) consisting of patients starting aromatase inhibitors (AI) as first-line therapy were used. mFAST-SeqS was performed using plasma of blood in which CTCs (CellSearch) were enumerated. The resulting aneuploidy score was correlated with categorized CTC count and associated with outcome. The aneuploidy score was significantly correlated with CTC count, but discordance was observed in 31.6% when applying cut-offs of 5. In both cohorts, aneuploidy score was a significant prognostic marker for both PFS and OS. In the Cox regression models, the HR for aneuploidy score for PFS was 2.52 (95% CI: 1.56-4.07), and the HR for OS was 2.37 (95% CI: 1.36-4.14). Results presented here warrant further investigations into the clinical utility of this marker in MBC patients.

Development of a Clinical Prediction Model for 1-Year Mortality in Patients With Advanced Cancer.

Importance: To optimize palliative care in patients with cancer who are in their last year of life, timely and accurate prognostication is needed. However, available instruments for prognostication, such as the surprise question ("Would I be surprised if this patient died in the next year?") and various prediction models using clinical variables, are not well validated or lack discriminative ability. Objective: To develop and validate a prediction model to calculate the 1-year risk of death among patients with advanced cancer. Design, Setting, and Participants: This multicenter prospective prognostic study was performed in the general oncology inpatient and outpatient clinics of 6 hospitals in the Netherlands. A total of 867 patients were enrolled between June 2 and November 22, 2017, and followed up for 1 year. The primary analyses were performed from October 9 to 25, 2019, with the most recent analyses performed from June 19 to 22, 2022. Cox proportional hazards regression analysis was used to develop a prediction model including 3 categories of candidate predictors: clinician responses to the surprise question, patient clinical characteristics, and patient laboratory values. Data on race and ethnicity were not collected because most patients were expected to be of White race and Dutch ethnicity, and race and ethnicity were not considered as prognostic factors. The models' discriminative ability was assessed using internal-external validation by study hospital and measured using the C statistic. Patients 18 years and older with locally advanced or metastatic cancer were eligible. Patients with hematologic cancer were excluded. Main Outcomes and Measures: The risk of death by 1 year. Results: Among 867 patients, the median age was 66 years (IQR, 56-72 years), and 411 individuals (47.4%) were male. The 1-year mortality rate was 41.6% (361 patients). Three prediction models with increasing complexity were developed: (1) a simple model including the surprise question, (2) a clinical model including the surprise question and clinical characteristics (age, cancer type prognosis, visceral metastases, brain metastases, Eastern Cooperative Oncology Group performance status, weight loss, pain, and dyspnea), and (3) an extended model including the surprise question, clinical characteristics, and laboratory values (hemoglobin, C-reactive protein, and serum albumin). The pooled C statistic was 0.69 (95% CI, 0.67-0.71) for the simple model, 0.76 (95% CI, 0.73-0.78) for the clinical model, and 0.78 (95% CI, 0.76-0.80) for the extended model. A nomogram and web-based calculator were developed to support clinicians in adequately caring for patients with advanced cancer. Conclusions and Relevance: In this study, a prediction model including the surprise question, clinical characteristics, and laboratory values had better discriminative ability in predicting death among patients with advanced cancer than models including the surprise question, clinical characteristics, or laboratory values alone. The nomogram and web-based calculator developed for this study can be used by clinicians to identify patients who may benefit from palliative care and advance care planning. Further exploration of the feasibility and external validity of the model is needed.

The effect of trastuzumab on cardiac function in patients with HER2-positive metastatic breast cancer and reduced baseline left ventricular ejection fraction.

We investigated the effect of trastuzumab on cardiac function in a real-world historic cohort of patients with HER2-positive metastatic breast cancer (MBC) with reduced baseline left ventricular ejection fraction (LVEF). Thirty-seven patients with HER2-positive MBC and baseline LVEF of 40% to 49% were included. Median LVEF was 46% (interquartile range [IQR] 44%-48%) and median follow-up was 18 months (IQR 9-34 months). During this period, the LVEF did not worsen in 24/37 (65%) patients, while 13/37 (35%) patients developed severe cardiotoxicity defined as LVEF <40% with median time to severe cardiotoxicity of 7 months (IQR 4-10 months) after beginning trastuzumab. Severe cardiotoxicity was reversible (defined as LVEF increase to a value <5%-points below baseline value) in 7/13 (54%) patients, partly reversible (defined as absolute LVEF increase ≥10%-points from nadir to a value >5%-points below baseline) in 3/13 (23%) patients and irreversible (defined as absolute LVEF increase <10%-points from nadir and to a value >5%-points below baseline) in 3/13 (23%) patients. Likelihood of reversibility was numerically higher in patients who received cardio-protective medications (CPM), including ACE-inhibitors, beta-blockers and angiotensine-2 inhibitors, compared to those who did not receive any CPM (71% vs 13%, P = .091). Sixty-five percent of patients who received trastuzumab for HER2-positive MBC did not develop severe cardiotoxicity during a median follow-up of 18 months, despite having a compromised baseline LVEF. If severe cardiotoxicity occurred, it was at least partly reversible in more than two-thirds of the cases. Risks and benefits of trastuzumab use should be balanced carefully in this vulnerable population.

Heat-induced BRCA2 degradation in human tumours provides rationale for hyperthermia-PARP-inhibitor combination therapies.

PURPOSE: Hyperthermia (40-44 °C) effectively sensitises tumours to radiotherapy by locally altering tumour biology. One of the effects of heat at the cellular level is inhibition of DNA repair by homologous recombination via degradation of the BRCA2-protein. This suggests that hyperthermia can expand the group of patients that benefit from PARP-inhibitors, a drug exploiting homologous recombination deficiency. Here, we explore whether the molecular mechanisms that cause heat-mediated degradation of BRCA2 are conserved in cell lines from various origins and, most importantly, whether, BRCA2 protein levels can be attenuated by heat in freshly biopted human tumours. EXPERIMENTAL DESIGN: Cells from four established cell lines and from freshly biopsied material of cervical (15), head- and neck (9) or bladder tumours (27) were heated to 42 °C for 60 min ex vivo. In vivo hyperthermia was studied by taking two biopsies of the same breast or cervical tumour: one before and one after treatment. BRCA2 protein levels were measured by immunoblotting. RESULTS: We found decreased BRCA2-levels after hyperthermia in all established cell lines and in 91% of all tumours treated ex vivo. For tumours treated with hyperthermia in vivo, technical issues and intra-tumour heterogeneity prevented obtaining interpretable results. CONCLUSIONS: This study demonstrates that heat-mediated degradation of BRCA2 occurs in tumour material directly derived from patients. Although BRCA2-degradation may not be a practical biomarker for heat deposition in situ, it does suggest that application of hyperthermia could be an effective method to expand the patient group that could benefit from PARP-inhibitors.

First-Line Palliative HER2-Targeted Therapy in HER2-Positive Metastatic Breast Cancer Is Less Effective After Previous Adjuvant Trastuzumab-Based Therapy.

BACKGROUND: Survival of patients with human epidermal growth receptor 2 (HER2)-positive metastatic breast cancer (MBC) has improved dramatically since trastuzumab has become available, although the disease eventually progresses in most patients. This study investigates the outcome (overall survival [OS] and time to next treatment [TNT]) in MBC patients pretreated with trastuzumab in the adjuvant setting (TP-group) compared with trastuzumab-naïve patients (TN-group) in order to investigate the possibility of trastuzumab resistance. PATIENTS AND METHODS: Patients treated with first-line HER2-targeted-containing chemotherapy were eligible for the study. A power analysis was performed to estimate the minimum size of the TP-group. OS and TNT were estimated using Kaplan-Meier curves and multivariable Cox proportional hazards models. RESULTS: Between January 1, 2000, and June 1, 2014, 469 patients were included, of whom 82 were in the TP-group and 387 were in the TN-group. Median OS and TNT were significantly worse in the TP-group compared with the TN-group (17 vs. 30 months, adjusted hazard ratio [HR] 1.84 [1.15-2.96], p = .01 and 7 vs. 13 months, adjusted HR 1.65 [1.06-2.58], p = .03) after adjustment for age, year of diagnosis, disease-free interval, hormone receptor status, metastatic site, and cytotoxic regimens. CONCLUSION: First-line trastuzumab-containing treatment regimens are less effective in patients with failure of adjuvant trastuzumab compared with trastuzumab-naïve patients and might be due to trastuzumab resistance. The impact of trastuzumab resistance on the response on dual HER2 blockade with trastuzumab and pertuzumab and how resistance mechanisms can be used in the optimization of HER2-targeted treatment lines need further investigation. IMPLICATIONS FOR PRACTICE: Evidence on the efficacy of palliative trastuzumab-based therapy after failure of trastuzumab in the adjuvant setting is limited because of a minority of patients treated with adjuvant trastuzumab in clinical trials. In this study, less clinical benefit of palliative trastuzumab-based therapy was observed in patients relapsing after adjuvant trastuzumab compared with no adjuvant trastuzumab treatment. Subgroup analyses and multivariable analyses revealed that this was independent of possible confounding factors, including adjuvant taxane-treatment. This might suggest a clinically meaningful impaired efficacy of trastuzumab after previous, in this case adjuvant, trastuzumab therapy. These results could have implications for treatment decision-making after short progression-free intervals on trastuzumab-containing regimens in the palliative setting.

A randomized phase 2 study exploring the role of bevacizumab and a chemotherapy-free approach in HER2-positive metastatic breast cancer: The HAT study (BOOG 2008-2003), a Dutch Breast Cancer Research Group trial.

BACKGROUND: To explore the role of bevacizumab and a chemotherapy-free approach, the authors evaluated the combination of bevacizumab, trastuzumab, and paclitaxel (HAT) and the regimen of trastuzumab and bevacizumab (HA) with the addition of paclitaxel after progression (HA-HAT) as first-line treatment for patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer. METHODS: In a noncomparative phase 2 trial, patients were randomized between HAT and HA-HAT. The primary endpoint was the progression-free rate at 1 year (1-year PFR). In the HA-HAT group, progression-free survival (PFS) was separately established for HA (PFS1) and HAT (PFS2). RESULTS: Eighty-four patients received HAT (n = 39) or HA-HAT (n = 45). The 1-year PFR was 74.4% (95% confidence interval [CI], 61.8%-89.4%) and 62.2% (95% CI, 49.6%-89.4%) in the HAT and HA-HAT arms, respectively. The median PFS was 19.8 months (95% CI, 14.9-25.6 months) in the HAT arm and 19.6 months (95% CI, 12.0-32.0 months) in the HA-HAT arm. In the HA-HAT arm, the median PFS1 was 10.4 months (95% CI, 6.2-15.0 months), and the median PFS2 was 8.2 months (95% CI, 7.0-12.6 months). The number and severity of adverse events were comparable between the arms. CONCLUSIONS: Both HAT and HA-HAT have promising activity in patients with HER2-positive metastatic breast cancer. In particular, starting with only targeted agents and delaying chemotherapy is worth further exploration. Cancer 2016;122:2961-2970. © 2016 American Cancer Society.

Toxicity of (neo)adjuvant chemotherapy for BRCA1- and BRCA2-associated breast cancer.

Treatment with (neo)adjuvant chemotherapy for breast cancer, as currently given, causes cell damage by induction of double-strand DNA breaks. Because BRCA1 and BRCA2 proteins play a role in the repair of DNA damage, the efficacy of (neo)adjuvant chemotherapy may be increased in BRCA1/2-associated breast cancer patients. As a downside, acute chemotherapy-related toxicity may also be increased. We selected all female patients who were treated at the Erasmus MC Cancer Institute, with (neo)adjuvant chemotherapy for primary or locoregional recurrence of breast cancer (PBC/LR) between January 1, 2004 and December 31, 2014. The primary outcome was the relative total dose intensity (RTDI), calculated for anthracyclines and taxanes separately. Secondary outcomes were the occurrence of febrile neutropenia, delay in chemotherapy administration, and switch to another chemotherapy regimen due to toxicity. In total, 701 patients treated for PBC/LR were eligible for data analyses, among which 85 BRCA1/2 mutation carriers (n = 67 BRCA1 and n = 18 BRCA2). The mean RTDI for anthracyclines was not significantly different between both groups (98.7 % in the BRCA1/2, 96.6 % in the sporadic group, p = 0.27). Also the mean RTDI for taxanes was not significantly different between the groups (93.6 % in the BRCA1/2-associated, 90.0 % in the sporadic group, p = 0.12). Linear regression analysis revealed no significant effect of BRCA1/2 mutation carriership on the RTDIs. No significant differences were found in the percentages of patients presenting with febrile neutropenia, having a delay in chemotherapy administration or switching to an altered chemotherapy regimen. Additionally, the odds ratios showed no significant effect of BRCA1/2 mutation carriership on the secondary outcome variables. (Neo)adjuvant chemotherapy-related toxicity was not different between BRCA1/2-associated and sporadic breast cancer patients suggesting that the DNA damage repair mechanism of non-cancer cells with only one normal copy of either the BRCA1 or BRCA2 gene is sufficiently functional to handle acute chemotherapy-associated toxicity.

Development and validation of an UPLC-MS/MS method for the quantification of tamoxifen and its main metabolites in human scalp hair.

The aim of this study was to validate an earlier developed high-performance highly sensitive ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method for quantification of tamoxifen and its three main metabolites (N-desmethyl-tamoxifen, 4-hydroxy-tamoxifen and 4-hydroxy-N-desmethyl-tamoxifen) in scalp hair. This non-invasive method might, by segmental analysis of hair, be useful in the determination of the concentration of drugs and its metabolites over time, which can be used to study a wide variety of clinical relevant questions. Hair samples (150-300 hair strands, cut as close to the scalp as possible from the posterior vertex region of the head) were collected from female patients taking tamoxifen 20mg daily (n=19). The analytes were extracted using a liquid-liquid extraction procedure with carbonate buffer at pH 8.8 and a mixture of n-hexane/isopropranol method, followed by UPLC-MS/MS chromatography, based on an earlier validated method. The calibration curves were linear in the range of 1.00-200 pmol for tamoxifen and N-desmethyl-tamoxifen, with lower limit of quantitation of 1.00 pmol and 0.100-20.0 pmol with lower limit of quantitation of 0.100 pmol for endoxifen and 4-hydroxy-tamoxifen. Assay performance was fair with a within-run and between-run variability less than 9.24 at the three quality control samples and less than 15.7 for the lower limit of quantitation. Importantly, a steep linear decline was observed from distal to proximal hair segments. Probably, this is due to UV exposure as we showed degradation of tamoxifen and its metabolites after exposure to UV-light. Furthermore, higher concentrations of tamoxifen were found in black hair samples compared to blond and brown hair samples. We conclude that measurement of the concentration of tamoxifen and its main metabolites in hair is possible, with the selective, sensitive, accurate and precise UPLC-MS/MS method. However, for tamoxifen, it seems not possible to determine exposure over time with segmental analysis of hair, probably largely due to the effect of UV irradiation. Further research should therefore focus on quantification of other anticancer drugs, in segmented scalp hair, that are less sensitive to UV irradiation.

Neutrophil-guided dosing of anthracycline-cyclophosphamide-containing chemotherapy in patients with breast cancer: a feasibility study.

The aim of this study was to investigate whether neutrophil-guided dose escalation of anthracycline-cyclophosphamide-containing chemotherapy (ACC) for breast cancer is feasible, in order to optimize outcome. Breast cancer patients planned for 3-weekly ACC were enrolled in this study. The first treatment cycle was administered in a standard BSA-adjusted dose. The absolute neutrophil count was measured at baseline and at day 8, 11 and 15 after administration of ACC. For patients with none or mild (CTC grade 0-2) neutropenia and no other dose-limiting toxicity, we performed a 10-25 % dose escalation of the second cycle with the opportunity to a further 10-25 % dose escalation of the third cycle. Thirty patients were treated in the adjuvant setting with either FE100C (n = 23) or AC (n = 4), or in the palliative setting with FAC (n = 3). Two out of 23 patients (9 %) treated with FEC did not develop grade 3-4 neutropenia after the first treatment cycle. Dose escalation was performed in these two patients (30 % in one and 15 % in the other patient). During dose escalation, there were no complications like febrile neutropenia. No patients treated with FAC or AC could be escalated, since all of them developed grade 3-4 neutropenia. We conclude that asymptomatic grade 3-4 neutropenia is likely to be achieved in the majority of patients with breast cancer treated with ACC according to presently advocated BSA-based dose levels. Escalation of currently advocated ACC doses without G-CSF, with a target of grade 3-4 neutropenia, is feasible, but only possible in a small proportion of patients. EudraCT 2010-020309-33.

Diagnostic and therapeutic ionizing radiation and the risk of a first and second primary breast cancer, with special attention for BRCA1 and BRCA2 mutation carriers: a critical review of the literature.

Occurrence of breast cancer is a well-known long-term side effect of ionizing radiation (both diagnostic and therapeutic). The radiation-induced breast cancer risk increases with longer follow-up, higher radiation dose and younger age of exposure. The risk for breast cancer following irradiation for lymphomas is well known. Although data regarding the carcinogenic risk of adjuvant radiotherapy for a primary breast cancer are sparse, an increased risk is suggested with longer follow-up mainly when exposed at younger age. Particularly, patients with a BRCA1/2 mutation might be more sensitive for the deleterious effects of ionizing radiation due to an impaired capacity of repairing double strand DNA breaks. This might have consequences for the use of mammography in breast cancer screening, as well as the choice between breast conserving therapy including radiotherapy and mastectomy at primary breast cancer diagnosis in young BRCA1/2 mutation carriers. Good data regarding this topic, however, are scarce, mainly due to constraints in the design of performed studies. In this review, we will discuss the current literature on the association between ionizing radiation and developing breast cancer, with particular attention to patients with a BRCA1/2 mutation.

Denosumab in breast cancer treatment.

The bone is the most common site to which breast cancer metastasises. Recently, denosumab, a fully human monoclonal antibody that binds to receptor activator of nuclear factor kappa-B ligand (RANKL) has been developed as a new targeted bone therapy. In a large randomized phase III study with a head-to-head comparison of denosumab to zoledronic acid in patients with bone metastases of breast cancer, denosumab significantly delayed the time to first skeletal related event. In the adjuvant setting denosumab significantly increased bone mineral density compared to placebo in a phase III study in patients treated with aromatase inhibitors. Preclinical data suggest an effect of denosumab on tumour growth and even on carcinogenesis. This review describes the current indications for denosumab in the various settings of breast cancer treatment, with special attention for efficacy, short and long term toxicity and other relevant issues for clinical practice. Furthermore possible and necessary future research questions are proposed.