Background

Eribulin is a non-taxane microtubule dynamics inhibitor that has been proven to prolong overall survival in patients with breast cancer. S-1, an oral anticancer drug, has demonstrated non-inferiority in overall survival (OS) to taxane as first-line chemotherapy for metastatic breast cancer (MBC). We previouly reported phase I trial results for the combination of these drugs with an overall response rate of 41.7% and median progression free survival (PFS) of 7.6 months. George W et.al (J Clin Oncol 2003) suggested that estrogen receptor negativity, the presence of three or more sites of disease, a short disease-free interval (1 to 24 months), and prior systemic therapy all predicted for impaired overall survival in their multivariate analysis. Considering these factors, we conducted a multicenter phase II study of this combination to further evaluate its safety and efficacy.

Background

Eribulin is a non-taxane microtubule dynamics inhibitor that has been proven to prolong overall survival in patients with advanced and recurrent breast cancer .S-1, an oral anticancer drug, composed of tegafur, gimestat and otastat potassium, has demonstrated non-inferiority in overall survival (OS) to taxane as first-line chemotherapy for metastatic breast cancer (MBC).We previouly reported phase I trial results for the combination of these drugs with an overall response rate of 41.7% and median progression free survival (PFS) of 7.6 months. George W et.al (J Clin Oncol 2003) suggested that estrogen receptor negativity, the presence of three or more sites of disease, a short disease-free interval (1 to 24 months), and prior systemic therapy all predicted for impaired overall survival in their multivariate analysis. Considering these factors, we conducted a multicenter phase II study of this combination to further evaluate its safety and efficacy.

Methods

Recurrent or advanced breast cancer patients previously treated with anthracycline or taxanes were enrolled from September 2014 to May 2016. Patients received Eribulin 1.4 mg/m² day1 and day8 intravenously and S-1 50 mg/m² from day1 to day14 orally. Primary objective was to investigate safety and efficacy. Secondary objectives were to evaluate PFS, OS and clinical benefit rate (CBR) using Response Criteria in Solid Tumors (RECIST).

Results

Thirty-two patients were enrolled this trial and 30 patients were evaluable. Objective response rate was 36.7%. There were 3 [10%] complete responses, 8 [26.7%] partial responses and 11 [36.7%] stable diseases. This combination therapy had a manageable safety profiles consistent with the known adverse effects of both drugs. The most common grade3-4 adverse events were neutropenia (22 [73.3%] of 32 patients), leukopenia (13 [43.3%] of 32 patients), febrile neutropenia (3 [9.4%] of 32 patients) and peripheral neuropathy (4 [12.5%] of 32 patients). CBR was 46.7%. The median overall survival and the median PFS was not reached.

Conclusions

We showed tolerability and clinical activity in this combination therapy in a subset of patients with poor prognosis. Eribulin in combination with S-1 may represent a promising treatment option for advanced or recurrent breast cancer patients.

Legal entity responsible for the study

Eisai

Funding

Eisai

Disclosure

All authors have declared no conflicts of interest.

Background

Postmastectomy radiotherapy (PMRT) has been strongly considered for patients with 1-3 positive axillary nodes (ALNs). In addition, the indications for PMRT are expanding to patients with negative ALNs but have multiple high-risk recurrence factors. However, For patients with isolated tumor cells. We aimed to determine the effects of PMRT on survival of patients with ITCs or ALNs micrometastases of breast cancer.

Methods

We identified patients with ITCs or ALNs micrometastases after mastectomy from the Surveillance, Epidemiology, and End Results database from 2004 to 2014. Overall survival (OS) and breast cancer-specific mortality (BCSM) were compared among patients received PMRT or not, using propensity score-matched analyses. Cox proportional hazards models and competing-risk models were performed in OS and BCSM analyses, respectively.

Results

We identified 11,622 eligible cases. PMRT was administered to 1,728 patients. Treatment was less frequent among patients who were older, patients with high-income, and patients with right-side tumor. OS at 5 years and 10 years were 88.1% and 74.2% in PMRT group, and were 87.8% and 77.3% in non-PMRT group, respectively. Five-year and 10-year cumulative BCSM rate were 6.4% and 12.3% in PMRT group, and were 6.6% and 14.1% in non-PMRT group, respectively. OS and BCSM were unaffected by PMRT after adjusting for multiple confounders (OS, hazard ratio, 0.92; 95% CI, 0.74 to 1.16; BCSM, subhazard ratio, 0.89; 95% CI, 0.67-1.18).

Conclusions

To our knowledge, this is the largest study to date of the effect of radiotherapy on survival in breast cancer with ITCs or ALN micrometastases. In this population-based study, we do not find survival benefit of PMRT on patients with ITCs or ALN micrometastases.

Legal entity responsible for the study

Sun Yat-sen University Cancer Center

Funding

None

Disclosure

All authors have declared no conflicts of interest.

Background

It is unclear whether perioperative fluoropyrimidine (FP) use impacts the efficacy of capecitabine in advanced breast cancer treatment.

Methods

Medical records of patients with advanced breast cancer who received capecitabine between 2008 and 2016 at National Cancer Center Hospital (Tokyo, Japan) were reviewed. Progression-free survival (PFS), overall survival (OS), tumor response, and adverse events (AEs) were compared between a FP group (prior perioperative FP use) and a non-FP group (no prior FP use). To evaluate the effect of prior perioperative FP use on survival outcomes, hazard ratios (HRs) for PFS and OS were estimated for the FP group compared with the non-FP group.

Results

A total of 289 patients (FP group: n = 106; non-FP group: n = 183) were analyzed. Patient characteristics were similar between the two groups. The median recurrence-free interval (RFI) was 3.94 (range: 0.27-20.11) years in the FP group and 4.24 (range: 0.27-27.07) years in the non-FP group (p = 0.402). The FP group had poorer PFS than the non-FP group (univariate HR: 1.33; 95% confidence interval [CI]: 1.03-1.72, p = 0.028; multivariate HR: 1.33; 95% CI: 1.02-1.73; p = 0.034). However, OS was similar between the groups (univariate HR: 1.16; 95% CI: 0.84-1.62; p = 0.368; multivariate HR: 1.06; 95% CI: 0.74-1.51; p = 0.755). Multivariate HRs for PFS for the FP group with short RFI and long RFI (cutoff: RFI=4 years) separately were 1.56 (95% CI: 1.06-2.28; p = 0.025) and 1.20 (95% CI: 0.84-1.70; p = 0.326), respectively. With different cutoffs (RFI=3, 4, and 5 years), the ranges of adjusted HRs for PFS were 1.32-1.67 with short RFI, and 1.00-1.25 with long RFI. A trend for larger HR for the FP group with short RFI than with long RFI was also seen for OS with different cutoffs of RFI. The response rate (FP group vs. non-FP group) was 21.0% vs. 14.8% (p = 0.306), and the disease control rate was 59.9% vs. 54.5% (p = 0.422). There was no significant difference in AEs between the two groups.

Conclusions

Capecitabine can be used for patients with advanced breast cancer with FP use history, as OS does not correlate with prior FP use. For patients with FP use history, RFI may be a relevant factor for treatment selection.

Legal entity responsible for the study

National Cancer Center Hospital

Funding

None

Disclosure

All authors have declared no conflicts of interest.

Background

Eribulin mesylate (ERI) demonstrated a survival benefit in patients with locally recurrent or metastatic breast cancer who previously received 2 or more chemotherapy regimens. Recently, we conducted Phase II study about the efficacy of ERI with trastuzumab (ERI+TRA) as late-line therapy for locally advanced or metastatic HER2-positive breast cancer (UMIN000012350), and reported that objective response rate (ORR) and median progression-free survival (mPFS) were 17% and 4.6 months. However, some patients who received prior pertuzumab (PER) and/or T-DM1 were enrolled in that study, there are limited data on the efficacy of ERI+TRA in those patients. The aim of this study was to assess the efficacy of this combination therapy based on prior PER and/or T-DM1 use.

Methods

In primary phase II study, patients with locally advanced or metastatic HER2 positive breast cancer who previously received at least one chemotherapeutic regimen, received ERI at 1.4 mg/m² intravenously (I.V.) on days 1 and 8 of each 21-day cycle with an initial TRA dose of 8 mg/kg I.V. on day 1, followed by 6 mg/kg of TRA on day 1 of each subsequent cycle. ORR, clinical benefit rate (CBR) and PFS were assessed in patients who had and had not received prior PER and/or T-DM1.

Results

Thirty-six patients (median age: 60.5 years) received ERI+TRA. 69.4% (n = 25) had previously treated with prior PER and/or T-DM1, defined as ‘prior’ patients. Remaining 30.6% (n = 11) without both agents were defined as ‘non-prior’ patients. In prior patients compared with non-prior patients, median number of prior treatment regimens was 4 (range, 1‐8) versus 3 (range, 1-7), respectively; ORR was 12.0% versus 27.3%, respectively; CBR was 24.0% versus 54.5%, respectively; mPFS was 4.3 versus 9.7 months, respectively.

Conclusions

ERI+TRA demonstrated lower efficacy than in non-prior patients, but CBR and PFS were 24.0% and 4.3 months, which was considered to be a clinically relevant treatment option in patients who received prior PER and/or T-DM1.

Clinical trial identification

UMIN000012350.

Legal entity responsible for the study

Nagoya Surgical Oncology Group

Funding

Eisai

Disclosure

All authors have declared no conflicts of interest.

Background

Varlitinib, a tyrosine kinase inhibitor of the ErbB family (EGFR, HER2 and HER4), showed anti-tumor activity in trastuzumab-resistant models and in patients with trastuzumab-resistant, chemotherapy-refractory MBC in a phase 1 study. This study compared the efficacy and safety of varlitinib plus capecitabine (VC) versus lapatinib plus capecitabine (LC) in HER2⁺ MBC patients who failed prior trastuzumab therapy.

Methods

The primary objective was to assess percentage change in tumor size at week 12. Objective response rate (ORR), safety and drug exposure were also assessed. Patients who received at least one dose of study treatment were included in primary analysis. Sensitivity analysis for primary objective and ORR were performed in patients who remained on study for more than 30 days.

Results

From Dec 2014 to Aug 2016, 24 patients were randomized to the VC arm (400mg BID) and 26 to the LC arm (1250mg QD) in 16 sites in 6 countries. Percentage of tumor size reduction was numerically higher in VC than LC (-31.00% vs. -19.37%, one-sided p = 0.132). ORR in the VC arm (40.9%) was similar to LC arm (45.5%), p = 1.000. Sensitivity analysis showed numerically superior ORR and statistically significant higher reduction of tumor size in VC compared to LC (60% vs. 45.5%, p = 0.508; mean, -34.6% vs.-19.4%, one-sided p = 0.075) All patients had at least 1 AE. Severe AE(s) were observed in 13 patients (54.2%) in the VC arm and 11(42.3%) in the LC arm. The most common AE was diarrhea (66.7%) in the VC arm and were diarrhea and palmar-plantar erythrodysaesthesia syndrome (both 50%) in the LC arm. Median intended exposure and percentage of intended dose were lower in the VC arm (115.5 days, 74.6%) indicating more frequent dose interruption, dose reduction and treatment discontinuation than the LC arm (135.0 days, 99.05%).

Conclusions

Sensitivity analysis showed greater tumor size reduction and improved ORR for VC arm when the combination was administrated for more than 30 days. Reduced intended exposure and dose intensity for the VC arm suggests a dose reduction of varlitinib may be considered when combined with capecitabine for the 2nd line treatment of HER2⁺ MBC.

Clinical trial identification

NCT02338245.

Legal entity responsible for the study

ASLAN pharmaceuticals

Funding

ASLAN pharmaceuticals

Disclosure

All authors have declared no conflicts of interest.

Background

The standard therapy for primary treatment of HER2-positive metastatic breast cancer (MBC) is combination therapy of pertuzumab (PER), trastuzumab (HER) and docetaxel (DTX). Although the effectiveness of trastuzumab emtansine (T-DM1) after HER treatment has been reported, there are few reports on the effectiveness of T-DM1 for patients treated with PER. We retrospectively investigated the effectiveness of T-DM1 on HER2-positive MBC previously treated with PER.

Methods

Between October 2013 and June 2017, 79 patients with HER2-positive MBC were treated with PER. 44 patients were investigated the subsequent treatment. 34 patients received T-DM1, and 10 patients received treatment other than T-DM1 after PER treatment.

Results

Median treatment line was 3.0 (1-9) vs 4.0 (1-9) in the T-DM1 treatment and other than T-DM1 treatment, respectively. The response rate was CR 0% vs 0%, PR 36.0% vs 25%, SD 32.0% vs 62.5%, PD 32.0% vs 12.5%, respectively. The objective response rate was 36.0% vs 20.0%. The clinical benefit rate was 48.0% vs 50.0%. Median time to treatment failure was 6.6 months vs 2.9 months, respectively. There was a significant difference in median overall survival; median not reached vs 19.6 months (p = 0.04).

Conclusions

OS was significantly better with administration of T-DM1 after PER treatment. Based on the results of this study, it was confirmed that efficacy of T-DM1 in patients with HER2-positive metastatic breast cancer previously treated with PER.

Legal entity responsible for the study

Koshi Matsui

Funding

None

Disclosure

All authors have declared no conflicts of interest.

Background

Breast cancer (BC) is the most frequently diagnosed disease and a leading cause of death in females globally. BC is also common in Pakistani females and one out of every nine female is at risk of developing BC. Information on the clinico-pathologic (CP) data of BC is limited especially from the northwest part of Pakistan. The purpose of this study was to profile the CP data of BC. This will clearly help us in assessing the CP characteristics of the disease and in public health intervention measures.

Methods

Data were extracted from consecutive medical files of BC patients at the IRNUM Hospital, Peshawar, Pakistan from 2014 to 2016. Demographic, clinical and pathological data were profiled. Data were analyzed for descriptive statistics, independent sample t test and Chi square test. Logistic regression was performed by stratifying patients according to the disease stage as early stage (stage I and II, ES) and late stage (stage III and IV, LS).

Results

Data of 362 patients with breast cancer was profiled. The mean age at diagnosis was 47.8 years. 8% of the patients were nulliparous and 5.2% of the patients had a positive family history of BC. The most common symptom was a lump in breast (82%), and left breast (54%) was the most common location of tumor. Most of the patients presented with LS disease (65%). ER+, PR+ and HER2+ cases were 62%, 47% and 49% respectively. The tumour was localized in 75% of the cases, while multifocal in 25% of the cases. The mean age (47.8 yrs) in the ES breast cancer is not statistically different from the mean age (47.7 yrs) in the LS breast cancer (p = 0.99). Lymph node positivity is associated with LS disease (p < 0.001) and it predicts LS disease (OR = 17.1, p < 0.001). Vascular invasion and HER2+ are also associated with LS disease (p = 0.06, p = 0.07, trending statistical significance).

Conclusions

Due to delayed consultation, patients present with late stage disease irrespective of age of patients. Thus, there is an urgent need for public health outreach programs directed towards awareness campaigns and the need for routine breast cancer screening. In addition, positive family history may be evaluated as potential risk factors in our population. Finally, a significant number of patients are ER+/PR+ and HER2+, which may promise targeted therapy options.

Legal entity responsible for the study

Office of Research, Khyber Medical University, Peshawar

Funding

None

Disclosure

All authors have declared no conflicts of interest.

Background

Breast cancer has become the most common cancer in Thai women since 2005. Unfortunately two thirds of the patients were diagnosed at advanced breast cancer (ABC) stage. Furthermore, most of these women were under the Universal Coverage by the government which does not provide sufficient coverage for certain critical medical treatments for ABC patients. The cost of treatments is even more of a pressing issue in Thailand. This study aimed to evaluate the cost-effectiveness of exemestane (EXE), a steroidal aromatase inhibitor (SAI), as treatment therapy following adjuvant non-steroidal aromatase inhibitor (NSAI) for hormonal responsive ABC in Thailand.

Methods

A Markov model was used to estimate the relevant costs and health outcomes over the patients' lifetimes using a social cost and benefit perspective. All future costs and outcomes were discounted at a rate of 3% per annum. The efficacy and cost of EXE and chemotherapy were based on a clinical trial that included a total of 18 post-menopausal hormonal responsive ABC patients. Utility values were derived directly from all patients using EQ-5D. Primary outcomes of interest were lifetime costs, quality adjusted life-years (QALYs) gained, and the incremental cost-effectiveness ratio (ICER) in US ($) per QALY gained. One-way and probabilistic sensitivity analyses (PSA) were conducted to investigate the effect of parameter uncertainty.

Results

In base case analysis, the EXE group had better clinical outcomes and lower lifetime costs. The incremental cost per QALY gained was US $-2,747 per QALY. The acceptability curve showed that the probability of EXE being cost-effective was 97% at the willingness to pay of 1 time of Thai Gross National Income per capita (GNI per capita), approximately US $4,673 per QALY gained.

Conclusions

At a social cost of paying 1 GNI per capita, EXE is highly effective and cost-saving regimen for the first-line treatment of post-menopausal ABC with hormone positive receptor in Thailand. This study provides key relevant information aiding policy makers to make informed decision making regarding resource allocation to include EXE into reimbursement plan.

Legal entity responsible for the study

Faculty of Medicine, Chiang Mai University

Funding

None

Disclosure

All authors have declared no conflicts of interest.

Background

The subanalysis of prospective randomized trials of E suggested E suppressed development of new lesion [NL] and it led to improvement of overall survival (Twelves, BCRT, 2015), however, behaviors of disease in real-world patients (pts) have not been well discussed.

Methods

Outcomes of HER2-MBC pts who received E at our institute from November 2011 to present were reviewed. Statistical analyses were performed using the chi-square test, the Kaplan-Meyer method.

Results

We identified total 128 (90 ER+, 38 ER-) HER2-MBC who received E at least 2 cycles in our institute. Median age at the initiation of E were as follows; overall, 58 (range 30-77); ER+, 60 (30-77); ER- 55.5 (32-71). Median number of regimens prior to E were as follows; overall, 1 (range 0-8); ER+, 1 (0-6); ER-, 2 (0-8). While all pts had a history of anthracycline and/or taxane in ER- subset, Number of involved organ were 2 (1-5) in overall and both subsets and no significant difference was seen in the pattern of visceral involvement. Most of (122/128, 95.5%) the pts was discontinued E therapy, and median time-to-treatment failure (TTF) were as follows; overall, 125.0 days (95% confidence interval [CI] 43.0-328.0); ER+, 134.0 days (95%CI 62.0-314.0); ER-, 104.0 (95%CI 42.0-230.0). Reasons for the discontinuation of E were as follows; progression of known lesion(s), 77 (63.1%); development of NL, 27 (22.1%), decrease of performance status, 11 (9.0%); intolerable toxicity, 6 (4.9%); other, 1 (0.9%). In ER- subset, development of NL was more frequently seen compared to ER+ subset, however, it was not statistically significant. (7/20 vs 10/67, P = 0.12, chi-square). Multivariate cox regression analyses disclosed some risk factors for TTF as follows; liver metastasis, hazard ratio [HR] 0.39, P < 0.05; soft tissue metastasis, HR 0.53, P < 0.05; ≥3 involved organs, HR 2.99, P < 0.05; taxane for early breast cancer, HR 2.50, P < 0.05. When limited to ER+ pts who received E as 2nd-line therapy (N = 40), only one (2.5%) pt developed NL and there was a positive relationship between TTF and OS after E (Spearman's roh=0.64, p < 0.0001).

Conclusions

Our single institutional review with some limitations disclosed eribulin monotherapy revealed equivalent effect shown in prospective studies.

Legal entity responsible for the study

Junichiro Watanabe

Funding

None

Disclosure

J. Watanabe: Advisory board member of Eisai Co., Ltd. Honoraria from Eisai Co., Ltd.

Background

Some risk factors (RFs) in the management of ER-positive, HER2-negative metastatic breast cancer (ER+HER2-MBC), such as a shorter disease-free interval (DFI), visceral involvement or high tumor burden, have been identified in prospective clinical trials; however, the utility of those RFs in the real world has not been well discussed.

Methods

We reviewed our medical records from 2002 to present to assess the utility of RFs (DFI≤24 months [DFI≤24M]; visceral metastases [VIS]; prior (neo)adjuvant anthracycline and/or taxane [A/T]; or ≥ 3 metastatic organs [≥3 ORG]) defined in the TURANDOT risk factor analyses (Brodowicz T, Br J Cancer, 2014), a first-line bevacizumab trial of HR+HER2-MBC patients. According to the analysis, patients with ≥2 RFs were classified as “high-risk (HiR)”, and others were classified as “low-risk (LoR)”. Statistical analyses were performed using the Kaplan-Meyer method and a multivariate COX regression analysis.

Results

We identified 311 ER+HER2-MBC (224 recurrent, 87 advanced) patients who underwent chemotherapy (CTx). The most common RF at the initiation of first-line CTx was VIS (N = 186, 59.8%), followed by A/T, ≥3 ORG and DFI≤24M. The distribution of RFs was as follows: 0 in 89 (28.6%), 1 in 93 (29.9%), 2 in 94 (30.2%), 3 in 30 (9.6%), and 4 in 5 (1.7%). The survival from the initiation of CTx (OSCTx) was significantly poorer in HiR patients than LoR ones (median 815.0 vs. 1062.0 days, p < 0.001, log-rank) in all MBC patients, as well as in 87 advanced BC patients (median 825.0 vs. 1160.0 days, P < 0.05, log-rank). There was no significant difference in the OSCTx between patients with 0 and 1 RF (P = 0.90). In addition, in recurrent BC (rBC) patients, there was no significant difference in the OSCTx between patients with 2 and ≥3 RFs (P = 0.10). Multivariate analyses revealed ≥3 ORG and DFI≤24M as significant RFs (P < 0.05) for all rBC patients (hazard ratios 1.61 and 1.49, respectively).

Conclusions

Our review suggests that RFs such as high tumor burden and shorter DFI identified in prospective randomized studies are applicable to patients in the real world, even with heterogeneous backgrounds.

Legal entity responsible for the study

Junichiro Watanabe

Funding

None

Disclosure

J. Watanabe: Honoraria from AstraZeneca Japan, Chugai Pharmaceuticals, Eisai, Novartis Pharma Japan, Taiho pharmaceuticals, and advisory board member of AstraZeneca Japan, Eisai.

All other authors have declared no conflicts of interest.

Background

In this study, we observe the patterns initial palliative treatment for premenopausal patients with HR-positive/HER2-negative MBC and determine if non-adherence to clinical guidelines are associated with worse clinical outcomes in terms of progression-free survival (PFS) and overall survival (OS) in the South Korean population.

Methods

A retrospective review was performed for premenopausal patients diagnosed with HR-positive MBC between October 1997 and May 2016 who received palliative systemic treatments at a large tertiary medical center. Survival outcomes were analyzed according to the palliative treatment received prior to disease progression.

Results

The review identified a total of 272 premenopausal patients with HR-positive/HER2-negative MBC. The patients were young (median age, 39 years), as per the premenopausal criteria. Chemotherapy alone was first-line palliative treatment in 78 patients, with endocrine therapy as the initial treatment in 133 patients. In 57 patients, the first line treatment was switched from chemotherapy to endocrine treatment prior to any disease progression. Both progression free survival and overall survival were significantly longer for chemotherapy-endocrine therapy (median PFS 18.2 months and OS 85.2 months) than for chemotherapy-alone (median PFS 12.6 months and OS 45.5 months) or endocrine therapy-alone (median PFS 7.0 months and OS 57.3 months) (all P values < 0.01). In multivariate analysis, chemotherapy-endocrine therapy was an independent predictive value for improved PFS and OS (hazard ratio [HR] 0.33, 95% CI 0.20-0.52, P < 0.001; HR 0.38, 95% CI 0.19-0.73, P = 0.004).

Conclusions

In our study population, chemotherapy alone was not objectively inferior to endocrine therapy as the initial palliative treatment. In addition, chemotherapy followed by endocrine therapy was associated with objective higher response rate than endocrine therapy alone. Further studies should explore the relationship between non-adherent treatment patterns and patient outcomes across the largely premenopausal breast cancer populations across Asian countries.

Legal entity responsible for the study

Prof. Yeon Hee Park

Funding

None

Disclosure

All authors have declared no conflicts of interest.