Purpose

Diarrhea is recognized as a common adverse event associated with tyrosine kinase inhibitors (TKIs), with those targeting the ErbB family of receptors being associated with the highest rate of diarrhea.

Methods

This paper reviews data on the incidence, timing, and duration of diarrhea associated with US Food and Drug Administration-approved ErbB family-targeted TKIs from the published literature, and sets forth recommendations for management.

Results

In the absence of anti-diarrheal prophylaxis the incidence of any-grade diarrhea varies and typically occurs early during the course of treatment. Although it is difficult to determine if the incidence and severity of diarrhea is related to inhibition of a particular kinase target because of the multi-targeted and overlapping activity of many agents, evidence suggests that second-generation TKIs with broader target profiles (i.e., afatinib, lapatinib, neratinib) result in a higher incidence of diarrhea compared with highly specific first- (erlotinib, gefitinib) or third- (osimertinib) generation agents. The mechanisms responsible for TKI-associated diarrhea are not fully understood and are likely multi-factorial, involving dysregulated ion transport, inflammation, and mucosal injury. Management strategies have been developed-and continue to be refined-to prevent and reduce the severity and duration of TKI-associated diarrhea. For agents associated with more significant symptoms, anti-diarrheal prophylaxis reduces the incidence and severity of diarrhea, and ongoing studies are evaluating specific strategies to further reduce incidence and duration of TKI-associated diarrhea.

Conclusions

Continued investigations into risk factors and pharmacogenomic markers for diarrhea may further improve management of this common toxicity.

Improvements in screening and adjuvant therapy for breast cancer are associated with decreased recurrence, which may have the effect of increasing the proportion of patients presenting with first-line de novo versus recurrent metastatic breast cancer (MBC). Here, we describe and compare patients with de novo versus recurrent human epidermal growth factor 2 (HER2)-positive MBC. registHER was a prospective observational cohort study (late 2003-early 2006) of 1,023 patients with HER2-positive MBC. Baseline characteristics, treatment patterns, and clinical outcomes were examined in patients with newly diagnosed de novo (n = 327) compared with recurrent HER2-positive MBC after prior treatment for early-stage disease (n = 674). Patients with de novo HER2-positive MBC were less likely to have lung metastases, more likely to have lymph node, bone, and/or liver metastases and >4 sites of metastases and more likely to receive combined or concurrent chemotherapy and hormonal therapy with or without trastuzumab than those with recurrent HER2-positive MBC. Median follow-up was 29 months. Median progression-free survival was 12.1 versus 9.3 months [hazard ratio = 0.716 (95 % confidence interval (CI) 0.617-0.831)], and overall survival was 41.7 versus 32.8 months [hazard ratio = 0.766 (95 % CI 0.633-0.928)] for patients with de novo versus recurrent HER2-positive MBC, respectively. Patients with recurrent HER2-positive MBC had similar outcomes regardless of whether they received prior adjuvant therapy, excluding hormonal therapy. Despite presenting with more advanced-stage disease and higher tumor burdens, patients with de novo HER2-positive MBC have more favorable clinical outcomes than those with recurrent HER2-positive MBC. These differences may be due to effects of prior drug exposure and could have implications for designing and interpreting clinical trials.

Background

We characterized the whole transcriptome of circulating tumor cells (CTCs) in stage II-III breast cancer to evaluate correlations with primary tumor biology.

Methods

CTCs were isolated from peripheral blood (PB) via immunomagnetic enrichment followed by fluorescence-activated cell sorting (IE/FACS). CTCs, PB, and fresh tumors were profiled using RNA-seq. Formalin-fixed, paraffin-embedded (FFPE) tumors were subjected to RNA-seq and NanoString PAM50 assays with risk of recurrence (ROR) scores.

Results

CTCs were detected in 29/33 (88%) patients. We selected 21 cases to attempt RNA-seq (median number of CTCs = 9). Sixteen CTC samples yielded results that passed quality-control metrics, and these samples had a median of 4,311,255 uniquely mapped reads (less than PB or tumors). Intrinsic subtype predicted by comparing estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) versus PAM50 for FFPE tumors was 85% concordant. However, CTC RNA-seq subtype assessed by the PAM50 classification genes was highly discordant, both with the subtype predicted by ER/PR/HER2 and by PAM50 tumors. Two patients died of metastatic disease, both of whom had high ROR scores and high CTC counts. We identified significant genes, canonical pathways, upstream regulators, and molecular interaction networks comparing CTCs by various clinical factors. We also identified a 75-gene signature with highest expression in CTCs and tumors taken together that was prognostic in The Cancer Genome Atlas and Molecular Taxonomy of Breast Cancer International Consortium datasets.

Conclusion

It is feasible to use RNA-seq of CTCs in non-metastatic patients to discover novel tumor biology characteristics.

Purpose

The potential utility of circulating tumor cells (CTCs) as liquid biopsies is of great interest. We hypothesized that CTC capture using EpCAM based gating is feasible for most breast cancer subtypes.

Results

Cancer cells could be recovered from all intrinsic subtypes of breast cancer with IE/FACS, however, claudin-low cell lines showed very low capture rates compared to the four other groups (p = 0.03). IE/FACS detection of CTC mimic cells was time sensitive, emphasizing controlling for pre-analytic variables in CTC studies. Median fluorescent intensity for flow cytometry and RNA flow cell type characterization were highly correlated, predicting for CTC isolation across molecular subtypes. RNA-Seq of IE/FACS sorted single cell equivalents showed high correlation compared to bulk cell lines, and distinct gene expression signatures compared to PB.

Materials and methods

Ten cell lines representing all major subtypes of breast cancer were spiked (as CTC mimics) into and recovered from peripheral blood (PB) using immunomagnetic enrichment followed by fluorescence-activated cell sorting (IE/FACS). Flow cytometry and RNA flow were used to quantify the expression of multiple breast cancer related markers of interest. Two different RNA-Seq technologies were used to analyze global gene expression of recovered sorted cells compared to bulk cell lines and PB.

Conclusions

EpCAM based IE/FACS detected and captured a portion of spiked cells from each of the 10 cell lines representing all breast cancer subtypes, including basal-like but not claudin-low cancers. The assay allows for the isolation of high quality RNA suitable for accurate RNA-Seq of heterogeneous rare cell populations.

Limited data exist regarding treatment patterns and outcomes in elderly patients with HER2-positive metastatic breast cancer (MBC). registHER is an observational study of patients (N = 1,001) with HER2-positive MBC diagnosed within 6 months of enrollment and followed until death, disenrollment, or June 2009 (median follow-up 27 months). Outcomes were analyzed by age at MBC diagnosis: younger (<65 years), older (65-74 years), elderly (≥75 years). For progression-free survival (PFS) and overall survival (OS) analyses of first-line trastuzumab versus nontrastuzumab, older and elderly patients were combined. Cox regression analyses were adjusted for baseline characteristics and treatments. Estrogen receptor/progesterone receptor status was similar across age groups. Underlying cardiovascular disease was most common in elderly patients. In patients receiving trastuzumab-based first-line treatment, elderly patients were less likely to receive chemotherapy. In trastuzumab-treated patients, incidence of left ventricular dysfunction (LVD) and congestive heart failure (CHF) (grades ≥ 3) were highest in elderly patients (LVD: elderly 4.8 %, younger 2.8 %, older 1.5 %; CHF: elderly 3.2 %, younger 1.9 %, older 1.5 %). Unadjusted median PFS (months) was significantly higher in patients treated with first-line trastuzumab than those who were not (<65 years: 11.0 vs. 3.4, respectively; ≥65 years: 11.7 vs. 4.8, respectively). In patients <65 years, unadjusted median OS (months) was significantly higher in trastuzumab-treated patients; in patients ≥65 years, median OS was similar (<65 years: 40.4 vs. 25.9; ≥65 years: 31.2 vs. 28.5). In multivariate analyses, first-line trastuzumab use was associated with significant improvement in PFS across age. For OS, significant improvement was observed for patients <65 years and nonsignificant improvement for patients ≥65 years. Elderly patients with HER2-positive MBC had higher rates of underlying cardiovascular disease than their younger counterparts and received less aggressive treatment, including less first-line trastuzumab. These real-world data suggest improved PFS across all age groups and similar trends for OS.

Background

Limited data are available describing the natural history of patients with HER2-positive and hormone receptor (HR)-positive metastatic breast cancer (MBC). We examined first-line treatment patterns and clinical outcomes in patients with HER2-positive, HR-positive MBC in a real-world setting.

Methods

registHER is a prospective, observational cohort of 1,023 patients with HER2-positive MBC diagnosed within 6 months of enrollment and followed until death, disenrollment, or June 2009 (median follow-up time: 27 months). Demographics, first-line treatment patterns, and clinical outcomes were examined for 530 HER2-positive, HR-positive patients. Progression-free survival (PFS) and overall survival (OS) times were examined. Multivariate analyses adjusted for baseline demographic and prognostic factors.

Results

HER2-positive, HR-positive patients receiving first-line trastuzumab plus hormonal therapy had significantly longer PFS times than patients who received hormonal therapy only (13.8 vs. 4.8 months; adjusted hazard ratio [HR]: 0.37, 95% confidence interval [CI]: 0.22-0.60); a nonsignificant reduction in OS time was observed (adjusted HR: 0.55, 95% CI: 0.27-1.14). Compared with patients who received first-line trastuzumab plus chemotherapy, patients who received first-line trastuzumab plus chemotherapy and hormonal therapy had longer median PFS times (20.4 months vs. 9.5 months; adjusted HR: 0.53, 95% CI: 0.42-0.68); a statistically significant reduction in risk of death was observed (adjusted HR: 0.50, 95% CI: 0.36-0.70). Sequential use of chemotherapy and hormonal therapy was associated with improved OS times when compared with concurrent use (adjusted PFS HR: 0.81, 95% CI: 0.54-1.21; adjusted OS HR: 0.48, 95% CI: 0.26-0.89).

Conclusions

These real-world data in patients with HER2-positive/HR-positive MBC provide evidence that, with or without chemotherapy, dual targeting of HRs and HER2 receptors is associated with significantly prolonged PFS and OS times.

Background

Amplification of the human epidermal growth factor receptor 2 (HER2) gene occurs in approximately 20% of invasive breast cancer cases and is associated with a more aggressive disease course than HER2-negative breast cancer. HER2-targeted therapies have altered the natural history of HER2-positive breast cancer, a trend that will likely further improve with the recent approval of new agents. A prospective, observational cohort study was designed and initiated to provide real-world insights into current treatment patterns, long-term survival, and patients' experiences with initial and subsequent treatments for HER2-positive metastatic breast cancer (MBC).

Methods/design

The Systematic Therapies for HER2-positive Metastatic Breast Cancer Study (SystHERs) is a US-based prospective observational cohort study enrolling patients ≥18 years of age with recently diagnosed HER2-positive MBC not previously treated with systemic therapy in the metastatic setting. The primary objective of the study is to identify treatment patterns and clinical outcomes in recently diagnosed patients in a variety of practice settings. Secondary objectives include comparative efficacy, safety, and patient-reported outcomes (PROs). Healthcare resource utilization is an exploratory end point. Tumor tissue and blood sample collection is optional.The SystHERs registry will enroll approximately 1000 patients over a 3-year period, after which the study will continue for ≥5 years, allowing for a maximum follow-up of 8 years. The treating physician will determine all care and the frequency of visits. PRO measures will be completed at study enrollment and every 90 days. Clinical data will be abstracted quarterly from patient records. The first patient was enrolled in June 2012, and preliminary descriptive data based on 25% to 30% of the final study population are expected at the end of 2013, and as of April 25, 2014, 386 patients are enrolled.

Discussion

SystHERs is expected to provide in-depth data on demographic, clinicopathological, and treatment patterns and their associations with clinical outcomes, PROs, and healthcare resource utilization. Tumor tissue and DNA repositories will also be established for use in future translational research.

Trial registration number

NCT01615068 (ClinicalTrials.gov identifier).

Data characterizing demographics, treatment patterns, and clinical outcomes in black patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) are limited. registHER is a large, observational cohort study of patients (n = 1,001) with HER2-positive MBC diagnosed ≤6 months of enrollment and followed until death, disenrollment, or June 2009 (median follow-up of 27 months). Demographics, treatment patterns, and clinical outcomes were described for black (n = 126) and white patients (n = 793). Progression-free survival (PFS) following first-line therapy and overall survival (OS) were examined. Multivariate analyses adjusted for baseline and treatment factors. Black patients were more likely than white patients to be obese (body mass index ≥30), to have diabetes, and to have a history of cardiovascular disease; they were also less likely to have estrogen receptor or progesterone receptor positive disease. In patients treated with trastuzumab, the incidence of cardiac safety events (grade ≥3) was higher in black patients (10.9 %) than in white patients (7.9 %). Unadjusted median OS and PFS (months) were significantly lower in black patients than in white patients (OS: black: 27.1, 95 % confidence interval [CI] 21.3-32.1; white: 37.3, 95 % CI 34.6-41.1; PFS: black: 7.0, 95 % CI 5.7-8.2; white: 10.2, 95 % CI 9.3-11.2). The adjusted OS hazard ratio (HR) for black patients compared with white patients was 1.29 (95 % CI 1.00-1.65); adjusted PFS HR was 1.29 (95 % CI 1.05-1.59). This real-world evaluation of a large cohort of patients with HER2-positive MBC shows poorer prognostic factors and independently worse clinical outcomes in black versus white patients. Further research is needed to identify potential biologic differences that could have predictive impact for black patients or that could explain these differences.

Background

Human epidermal growth factor receptor 2 (HER2)-positive breast cancer is a particularly aggressive form of the disease, and ultimately progresses in patients with metastases on standard therapies. Anthracyclines, such as doxorubicin, are an effective treatment for HER2-positive breast cancer, particularly when administered in combination with trastuzumab - however, doxorubicin-related cardiotoxicity has limited its use. Many patients are therefore never treated with anthracyclines, even upon disease progression, despite the potential for benefit. MM-302 is a novel, HER2-targeted antibody-liposomal doxorubicin conjugate that specifically targets HER2-overexpressing cells. Preclinical and Phase 1 data suggest that MM-302, as a monotherapy or in combination with trastuzumab, could be effective for managing previously treated, anthracycline-naïve, HER2-positive breast cancer, without the cardiotoxicity observed with free doxorubicin formulations.

Methods/design

HERMIONE is an open-label, multicenter, randomized (1:1) Phase 2 trial of MM-302 plus trastuzumab versus chemotherapy of physician's choice (gemcitabine, capecitabine, or vinorelbine) plus trastuzumab planned to enroll 250 anthracycline-naïve patients with locally advanced/metastatic HER2-positive breast cancer. Key inclusion criteria are: previous treatment with trastuzumab (with or without pertuzumab) in any setting; refractory or intolerant to pertuzumab (refractory to pertuzumab defined as progression in the locally advanced or metastatic setting, or disease recurrence during or within 12 months of completing pertuzumab-containing neoadjuvant and/or adjuvant therapy); and disease progression on, or intolerant to, ado-trastuzumab emtansine for locally advanced or metastatic disease. The trial is currently being conducted at sites in the USA, Canada, and Western Europe. Treatment will be administered in 21-day cycles, and will be continued until disease progression or unacceptable toxicity. The primary endpoint is independently assessed progression-free survival (PFS). Tumor response will be assessed every 6 weeks, and defined according to RECIST v1.1. Secondary endpoints include investigator-assessed PFS, overall survival (OS), OS rates at 6 months and 1 year, objective response rates, safety and tolerability, quality of life, and the pharmacokinetic profile of MM-302 plus trastuzumab.

Discussion

The HERMIONE study will evaluate the efficacy and safety of MM-302 plus trastuzumab in patients with refractory HER2-positive advanced/metastatic breast cancer for whom there are no standard of care therapies with a proven survival advantage.

Trial registration

Clinicaltrials.gov identifier: NCT02213744 . Registration date: 06AUG2014.

BACKGROUND:Limited data exist describing real-world treatment of de novo and recurrent HER2-positive metastatic breast cancer (MBC). MATERIALS AND METHODS:The Systemic Therapies for HER2-Positive Metastatic Breast Cancer Study (SystHERs) was a fully enrolled (2012-2016), observational, prospective registry of patients with HER2-positive MBC. Patients aged ≥18 years and ≤6 months from HER2-positive MBC diagnosis were treated and assessed per their physician's standard practice. The primary endpoint was to characterize treatment patterns by de novo versus recurrent MBC status, compared descriptively. Secondary endpoints included patient characteristics, progression-free and overall survival (PFS and OS, by Kaplan-Meier method; hazard ratio [HR] and 95% confidence interval [CI] by Cox regression), and patient-reported outcomes. RESULTS:Among 977 eligible patients, 49.8% (n = 487) had de novo and 50.2% (n = 490) had recurrent disease. A higher proportion of de novo patients had hormone receptor-negative disease (34.9% vs. 24.9%), bone metastasis (57.1% vs. 45.9%), and/or liver metastasis (41.9% vs. 33.1%), and a lower proportion had central nervous system metastasis (4.3% vs. 13.5%). De novo patients received first-line regimens containing chemotherapy (89.7%), trastuzumab (95.7%), and pertuzumab (77.8%) more commonly than recurrent patients (80.0%, 85.9%, and 68.6%, respectively). De novo patients had longer median PFS (17.7 vs. 11.9 months; HR, 0.69; 95% CI, 0.59-0.80; p < .0001) and OS (not estimable vs. 44.5 months; HR, 0.55; 95% CI, 0.44-0.69; p < .0001). CONCLUSION:Patients with de novo versus recurrent HER2-positive MBC exhibit different disease characteristics and survival durations, suggesting these groups have distinct outcomes. These differences may affect future clinical trial design. Clinical trial identification number. NCT01615068 (clinicaltrials.gov). IMPLICATIONS FOR PRACTICE:SystHERs was an observational registry of patients with HER2-positive metastatic breast cancer (MBC), which is a large, modern, real-world data set for this population and, thereby, provides a unique opportunity to study patients with de novo and recurrent HER2-positive MBC. In SystHERs, patients with de novo disease had different baseline demographics and disease characteristics, had superior clinical outcomes, and more commonly received first-line chemotherapy and/or trastuzumab versus those with recurrent disease. Data from this and other studies suggest that de novo and recurrent MBC have distinct outcomes, which may have implications for disease management strategies and future clinical study design.