Impacts of clinicopathological factors on efficacy of trastuzumab deruxtecan in patients with HER2-positive metastatic breast cancer

BackgroundThe previous second-line treatment for HER2-positive metastatic breast cancer were ado-trastuzumab emtansine (T-DM1); however, its activity is decreased in tumors with heterogenous, reduced, or loss of HER2 expression. Trastuzumab deruxtecan (T-DXd) has recently been developed as a novel antibody-drug conjugate to overcome resistance to T-DM1. However, clinical evidence on its ability to overcome this resistance is limited.Materials and methodsWe retrospectively analyzed data for patients with HER2-positive metastatic breast cancer who received T-DXd at our institution from April 2020 to March 2021. We evaluated the associations between clinicopathological and molecular biomarkers and the efficacy of T-DXd.ResultsTwenty-two patients were enrolled in this study. The median progression-free survival (PFS) was 9.7 months (95% confidence interval [CI], 7.0–not reached [NR]), and the objective response rate (ORR) was 61.9%. The ORR and PFS were comparable between patients with HER2 immunohistochemistry scores of 3+ and 2+/1+ at initial diagnosis (ORR: 50.0% vs. 72.7%, p = 0.39; median PFS, 9.7 months [95%CI, 2.6–NR] vs. 8.3 months [95%CI, 7.1–NR]; hazard ratio, 1.86 [95%CI, 0.53–6.57], p = 0.34). Two patients with heterogenous HER2 expression had a partial response or long stable disease (≥6 months). Three of four patients with re-biopsy samples after anti-HER2 targeted therapy and with latest HER2 immunohistochemistry scores of 1+ experienced partial responses (75.0%) to T-DXd, but none had responded to prior T-DM1.ConclusionsT-DXd demonstrated favorable activity in clinical practice. Moreover, T-DXd showed meaningful benefit in patients with heterogeneity, reduction, or loss of HER2 expression.     

Efficacy of trastuzumab emtansine (T-DM1) and lapatinib after dual HER2 inhibition with trastuzumab and pertuzumab in patient with metastatic breast cancer: Retrospective data from a French multicenter real-life cohort

PurposeTrastuzumab-emtansine (T-DM1), as well as lapatinib plus capecitabine were proven effective in two Phase III studies, following first-line trastuzumab plus a taxane. The introduction of dual HER2 blockade by trastuzumab and pertuzumab as first-line has positioned T-DM1 into second-line, and lapatinib plus capecitabine beyond, without formal evaluation of these strategies.MethodsESME Data Platform (NCT03275311) included individual data from all patients aged ≥18 years, in whom first-line treatment for metastatic breast cancer (MBC) was initiated between January 1, 2008 and December 31, 2016 in one of the 18 French Comprehensive Cancer Centers. The efficacy of T-DM1 and lapatinib plus capecitabine combination, following double blockade associating trastuzumab and pertuzumab were evaluated in this national real-life database. Eligibility criteria were: female, MBC, HER2+ tumor, first-line taxane-based chemotherapy and dual HER2-blockage by trastuzumab plus pertuzumab. Cohort A received second-line T-DM1, and Cohort B second-line T-DM1 and third or fourth-line lapatinib plus capecitabine.ResultsCohort A comprised 233 patients, and Cohort B 47 patients. Median progression-free survival (PFS) was 7.1 months in Cohort A and 4.6 months in Cohort B. Median overall survival were 36.7 months and 12.9 months, respectively. PFS was significantly dependent on the preceding treatment line's duration. In cohort A, HER2 expression status was a significant predictive factor of PFS.ConclusionFirst-line trastuzumab plus pertuzumab do not markedly diminish T-DM1's efficacy in second-line. Similarly, sequential treatment with trastuzumab plus pertuzumab then T-DM1 does not noticeably modify the efficacy of lapatinib plus capecitabine.     

Efficacy of neoadjuvant treatment with or without pertuzumab in patients with stage II and III HER2-positive breast cancer: a nationwide cohort analysis of pathologic response and 5-year survival

BackgroundPathologic complete response (pCR) rates in early stage HER2-positive breast cancer improved after pertuzumab was added to neoadjuvant treatment. However, survival benefit is less-well established and seems mostly limited to node-positive patients. We used national cancer registry data to compare outcomes of patients treated with and without pertuzumab.MethodsWe identified stage II-III HER2-positive breast cancer patients treated with neoadjuvant trastuzumab-based chemotherapy between November 2013 until January 2016 from the Netherlands Cancer Registry. During that period pertuzumab was only available in the 37 hospitals that participated in the TRAIN-2 study. Missing grade and pCR-status were obtained from the Dutch Pathology Registry (PALGA) and cause of death from Statistics Netherlands. We used multiple imputation to impute missing data, multivariable logistic regression to evaluate the association between pertuzumab and pCR (ypT0/is, ypN0) and multivariable Cox regression models for overall survival and breast cancer specific survival (BCSS).ResultsWe identified 1124 patients of whom 453 received pertuzumab. Baseline characteristics were comparable, although tumor grade was missing more often in patients treated without pertuzumab (12% vs. 2%). Pertuzumab improved pCR rates (41% vs 65%, adjusted odds ratio [aOR] 2.91; 95% CI:2.20–3.94). After a median follow-up of 6.0 years, 5-year BCSS rates were 95% and 98% respectively (adjusted hazard ratio [aHR]: 0.58; 95% CI:0.36–0.95). Younger patients derived more benefit from pertuzumab, but no other significant interactions were found.ConclusionThese results support earlier data of a small survival benefit with the addition of pertuzumab to trastuzumab-based neoadjuvant chemotherapy which is most meaningful in younger patients.     

Impact of body mass index on overall survival in patients with metastatic breast cancer

BackgroundHigh Body mass index (BMI) is a risk factor for breast cancer among postmenopausal women and an adverse prognostic factor in early-stage. Little is known about its impact on clinical outcomes in patients with metastatic breast cancer (MBC).MethodsThe National ESME-MBC observational cohort includes all consecutive patients newly diagnosed with MBC between Jan 2008 and Dec 2016 in the 18 French comprehensive cancer centers.ResultsOf 22 463 patients in ESME-MBC, 12 999 women had BMI data available at MBC diagnosis. Median BMI was 24.9 kg/m² (range 12.1–66.5); 20% of women were obese and 5% underweight. Obesity was associated with more de novo MBC, while underweight patients had more aggressive cancer features. Median overall survival (OS) of the BMI cohort was 47.4 months (95% CI [46.2–48.5]) (median follow-up: 48.6 months). Underweight was independently associated with a worse OS (median OS 33 months; HR 1.14, 95%CI, 1.02–1.27) and first line progression-free survival (HR, 1.11; 95%CI, 1.01; 1.22), while overweight or obesity had no effect.ConclusionOverweight and obesity are not associated with poorer outcomes in women with metastatic disease, while underweight appears as an independent adverse prognostic factor.     

Long term outcome data from the EORTC 75111-10114 ETF/BCG randomized phase II study: Pertuzumab and trastuzumab with or without metronomic chemotherapy for older patients with HER2-positive metastatic breast cancer,followed by T-DM1 after progression

IntroductionOlder patients are at higher risk of chemotherapy-induced toxicity, raising interest in less toxic anti-HER2 regimens for older persons with HER2-positive (HER2+) metastatic breast cancer (MBC).Patients and methodsThis phase II study randomized (1:1) patients with HER2+ MBC, aged 70+ or frail 60+, to first line chemotherapy with metronomic oral cyclophosphamide (M) + Trastuzumab (T) and Pertuzumab (P) or TP alone. T-DM1 was offered in case of progression.ResultsIn total, 39 and 41 patients were randomized to TP and TPM arm respectively. Median follow-up is 54.0 months. 24-month PFS was 18.7% (95% CI 8.2–32.4) and 28.7% (95% CI 15.8–43.0), respectively. A total of 49 (61.3%) patients died of whom 37 (75.5%) from disease progression; number of deaths per arm was 27 (69.2%) for TP and 22 (53.7%) for TPM. There was no significant difference in OS between the two arms (median OS TP vs TPM: 32.1 vs 37.5 months, p 0.25). Among the 40 patients who have started T-DM1 after disease progression on TP/TPM, PFS rate at 6 months after start of T-DM1 was 43.6% (95% CI: 27.7–58.5) and grade 3 or higher AE occurred in 18 pts (45%).ConclusionsMetronomic chemotherapy-based dual blockade (TPM), followed by T-DM1 after progression, provides an active and relatively well tolerated treatment option in an older/frail HER2+ MBC population, with a median survival of over 3 years. Nevertheless, the majority of this older/frail population died from breast cancer, highlighting the need for well tolerated and efficacious treatments in these patients.     

Efficacy of CT-P6 (trastuzumab biosimilar) versus reference trastuzumab in combination with pertuzumab in HER2-positive early-stage breast cancer: Preclinical and real-life clinical data

After the expiration of trastuzumab data exclusivity, biosimilar drugs were approved by regulatory agencies; among them, CT-P6 which was approved for the treatment of HER2-positive early- and advanced-breast cancer (BC) in 2018. Yet, reference trastuzumab (RTZ) is often combined with pertuzumab in early BC (EBC) patients treated with chemotherapy as it significantly improves the pathological complete response rate. Unfortunately, scarce preclinical and clinical data exists about the combination of CT-P6, pertuzumab and chemotherapy. Therefore, our aim was to study in vitro and in a retrospective cohort of EBC patients, whether CT-P6 was equivalent to RTZ when combined with pertuzumab with or without taxanes. In BT-474 and SKBR3 HER2+ cells we found that CT-P6 alone or in combination with pertuzumab had the same negative effect on cell proliferation, colony formation and HER2 downregulation as well as downstream activation, as RTZ. Adding paclitaxel to these treatments increased their effectivity to a similar extent. In HER2 1+ neuregulin-secreting MB-MDA-175 cells, combinations of CT-P6 or RTZ with pertuzumab were also effective, and mainly dependent on HER3:HER2 heterodimerization. In a retrospective cohort of 44 EBC HER2+ patients treated with neoadjuvant RTZ or CT-P6 in combination with pertuzumab and chemotherapy, we found no differences in efficacy or in adverse events. Moreover, the costs of CT-P6-based treatments were reduced by 1474.07 €/patient. All together we provide pre-clinical and clinical evidence of the equivalence of CT-P6 in combination with pertuzumab and chemotherapy and suggest studying these combinations also in HER2 low/negative BC patients.     

Survival outcomes of breast cancer patients with brain metastases: A multicenter retrospective study in Korea (KROG 16–12)

PurposeThis study evaluated the influence of prognostic factors and whole brain radiotherapy (WBRT) on overall survival (OS) of breast cancer (BC) patients with brain metastases (BM).Methods and materialsMedical records of 730 BC patients diagnosed with BM from 2000 to 2014 at 17 institutions were retrospectively reviewed. OS was calculated from BM diagnosis. Median follow-up duration was 11.9 months (range, 0.1–126.2).ResultsMedian OS was 15.0 months (95% CI: 14.0–16.9). Patients with different BC-specific graded prognostic assessment (GPA) scores showed significant differences (p < 0.001) in OS. In multivariate analysis, histologic grade 3 (p = 0.014), presence of extracranial metastasis (p < 0.001), the number of BM (>4; p = 0.002), hormone receptor negativity (p = 0.005), HER2-negativity (p = 0.003), and shorter time interval (<30 months) between BC and BM diagnosis (p = 0.007) were associated with inferior OS. By summing the β-coefficients of variables that were prognostic in multivariate analyses, we developed a prognostic model that stratified patients into low-risk (≤0.673) and high-risk (>0.673) subgroups; the high-risk subgroup had poorer median OS (10.1 months, 95% CI: 7.9–11.9 vs. 21.9 months, 95% CI: 19.5–27.1, p < 0.001). Univariate and multivariate analyses of propensity score-matched patients diagnosed with BM ≥ 30 months after BC diagnosis (n = 389, “late BM”) revealed that WBRT-treated patients showed superior OS compared to non-WBRT-treated patients (p = 0.070 and 0.030, respectively).ConclusionOur prognostic model identified high-risk BC patients with BM who might benefit from increased surveillance; if validated, our model could guide treatment selection for such patients. Patients with late BM might benefit from WBRT as initial local treatment.     

The efficacy and safety of paclitaxel plus bevacizumab therapy in breast cancer patients with visceral crisis

BackgroundVisceral crisis in metastatic breast cancer (MBC) is defined as severe organ dysfunction requiring rapidly efficacious therapy. Although weekly paclitaxel plus bevacizumab (wPTX + BV) achieves a high response rate in human epidermal growth factor receptor 2 (HER2)-negative MBC, the efficacy and safety of wPTX + BV for visceral crisis is unclear.MethodsWe retrospectively investigated patients with MBC with visceral crisis who received wPTX + BV. Visceral crisis was defined as follows: liver dysfunction (aspartate or alanine aminotransferase >200 U/L or total bilirubin >1.5 mg/dl), respiratory dysfunction (carcinomatous lymphangiomatosis, SpO₂ <93% in ambient air or required thoracentesis), superior vena cava (SVC) syndrome, or bone marrow carcinomatosis. The primary outcome was the proportion of patients on-treatment with wPTX + BV after 12 weeks. We also investigated time to treatment failure (TTF), overall survival (OS), objective response rate (ORR), and adverse events.ResultsA total of 44 patients with respiratory dysfunction (n = 29), liver dysfunction (n = 10), bone marrow carcinomatosis (n = 7), and SVC syndrome (n = 2) were eligible for this investigation. The proportion of patients on-treatment with wPTX + BV after 12 weeks was 63% (30/44), and the other patients discontinued wPTX + BV because of adverse events (n = 5) and disease progression (n = 9). Median TTF and OS, and the ORR were 131 days and 323 days, and 41%, respectively. No treatment-related death occurred.Conclusion: wPTX + BV achieved favorable efficacy and safety for treating patients with visceral crisis and may therefore be considered an option for the treatment of this acutely severe clinical condition.     

Trastuzumab deruxtecan versus trastuzumab emtansine for patients with human epidermal growth factor receptor 2-positive metastatic breast cancer: A cost-effectiveness analysis

BackgroundDESTINY-Breast03 (NCT03529110) was the first global phase III study to assess the antitumor activity of trastuzumab deruxtecan (T-DXd) compared to trastuzumab emtansine (T-DM1) in 2022. However, the balance between efficacy and cost of T-DXd remains unclear. As a result, the present study's goal is to investigate the cost-effectiveness of T-DXd vs T-DM1 as a second-line treatment for patients with HER2-positive MBC from the US and Chinese payer's perspectives.MethodsA Markov model with a 20-year time horizon was developed to evaluate the overall cost of patient treatment, incremental cost-effectiveness ratio (ICER), quality-adjusted life-years (QALYs), and life-years (LYs) in the US and China at WTP levels of 150,000/QALY and 37,653/QALY, respectively (3 times GDP per capita in 2021). Key data were gathered from the US government's official website, the Xiangya Hospital of Central South University, and published literature. To determine the model's stability, a sensitivity analysis was performed. A subgroup analysis was also implemented.ResultsCompared with T-DM1, treatment with T-DXd generated an additional 1.672 QALYs (2.796 LYs), resulting in an ICER of $13,342/QALY (US) and $186,017/QALY (China). The cost of drugs is the most influential factor in the American and Chinese models. Subgroup analysis revealed that the T-DXd and T-DM1 regimens were more cost-effective at reducing the risk of death in the US and Chinese HER2-positive MBC patients.ConclusionT-DXd as second-line treatment could gain more health benefits for HER2-positive MBC patients in comparison with T-DM1, which is considered to be cost-effective in the US but not in China.     

Efficacy and safety of everolimus plus exemestane in patients with HR+, HER2− advanced breast cancer progressing on/after prior endocrine therapy in routine clinical practice: Primary results from the non-interventional study,STEPAUT

BackgroundSTEPAUT, an Austrian non-interventional study, evaluated the safety and efficacy of everolimus plus exemestane in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) advanced breast cancer (ABC) recurring/progressing on/after nonsteroidal aromatase inhibitors (NSAIs) in routine clinical practice.MethodsPostmenopausal women with HR+, HER2− ABC progressing on/after NSAIs receiving everolimus plus exemestane in accordance with routine practice and the current version of Summary of Product Characteristics were eligible. Planned individual observation period corresponded to the duration of treatment until formal study end.ResultsOverall, 236 patients (median age: 65 years) were enrolled at 17 sites across Austria. The median progression-free survival (mPFS) in the overall population was 9.5 months (95% confidence interval [CI]: 8.6–10.7 months). The mPFS (95% CI) in patients who received everolimus 10 and 5 mg was 9.9 months (7.3–11.5 months) and 8 months (4.7–10.7 months), respectively. The median time to progression was numerically longer in patients who had a therapy break (11.9 months, 95% CI: 10.0–14.6 months) versus those who did not have any therapy break (10.7 months, 95% CI: 8.9–12.6 months). Patients experienced grade 1 (53.7%), grade 2 (35.9%), grade 3 (9.9%), grade 4 (0.2%) adverse events (AEs). The most common AEs of any grade were stomatitis, mucositis (53.8%), rash, exanthema (29.7%), loss of appetite, nausea (28.4%).ConclusionsReal-world safety and efficacy data from STEPAUT were consistent with results from BOLERO-2, supporting everolimus plus exemestane as a suitable treatment option for HR+, HER2− ABC recurring/progressing on/after NSAIs.     

Peripheral cytotoxic T lymphocyte predicts first-line progression free survival in HER2-positive advanced breast cancer

BackgroundThe role of peripheral blood lymphocyte (pBL) in breast cancer has long been studied. However, the predictive role of pBL in advanced breast cancer (ABC) is poorly understood.MethodsA total of 303 patients with ABC were consecutively recruited at our center between January 2015 and September 2019. At baseline, pBL subtypes were detected in all patients with 229 blood samples available for circulating tumor DNA (ctDNA) detection. pBL was analyzed through flow cytometry. ctDNA-based gene mutations were detected using next generation sequencing. The cutoff value of pCTL was estimated by X-tile software. Progression free survival (PFS) was estimated by Kaplan-Meier curve and Cox hazard proportion regression model, with difference detection by log-rank test.ResultsMedian follow-up time of the study was 21.0 months. The median age of diagnosis was 52.0 years. Among the pBL subtypes, only pCTL level was found predictive for PFS in the HER2+ patients whom received anti-HER2 therapy (13.1 vs. 5.6 months, P = 0.001). However, the predictive role of pCTL was not found in HR-positive (P = 0.716) and TNBC (P = 0.202). pCTL high associated with suppressive immune indictors including lower CD4/CD8 ratio (P = 0.004) and high level of Treg cell (P = 0.004). High occurrence of FGFR1 amplification which has been reported as immune suppressor was also found in HER2+ patients with pCTL high (22.2% vs. 4.3%, P = 0.048).ConclusionsHigher pCTLs level associated with shorter PFS and FGFR1 mutation in HER2+ ABC patients.     

Safety and efficacy of ribociclib plus letrozole in patients with HR+, HER2– advanced breast cancer: Results from the Spanish sub-population of the phase 3b CompLEEment-1 trial

BackgroundBreast cancer is the most common malignancy and the second leading cause of cancer-related mortality in Spanish women. Ribociclib in combination with endocrine therapy (ET) has shown superiority in prolonging survival in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) advanced breast cancer (ABC) vs. ET alone.MethodsCompLEEment-1 is a single-arm, open-label phase 3b trial evaluating ribociclib plus letrozole in a broad population of patients with HR+, HER2– ABC. The primary endpoints were safety and tolerability. Here we report data for Spanish patients enrolled in CompLEEment-1.ResultsA total of 526 patients were evaluated (median follow-up: 26.97 months). Baseline characteristics showed a diverse population with a median age of 54 years. At study entry, 56.5% of patients had visceral metastases and 8.7% had received prior chemotherapy for advanced disease. Rates of all-grade and Grade ≥3 adverse events (AEs) were 99.0% and 76.2%, respectively; 21.3% of patients experienced a serious AE, and 15.8% of AEs led to treatment discontinuation. AEs of special interest of neutropenia, increased alanine aminotransferase, increased aspartate aminotransferase and QTcF prolongation occurred in 77.8%, 14.8%, 11.4% and 4.0% of patients, respectively. Patients aged >70 years experienced increased rates of all-grade and Grade ≥3 neutropenia and anemia. Efficacy results were consistent with the global study.ConclusionsResults from Spanish patients enrolled in CompLEEment-1 are consistent with global data showing efficacy and a manageable safety profile for ribociclib plus letrozole treatment in patients with HR+, HER2− ABC, including populations of interest (NCT02941926).Trial registrationClinicalTrials.gov NCT02941926     

Clinical outcome of adjuvant radiotherapy for squamous cell carcinoma of the breast; a multicenter retrospective cohort study

BackgroundBecause primary squamous cell carcinoma (SCC) of the breast is a rare disease, the standard therapy has not been established. We examined the clinical outcomes of postoperative adjuvant radiotherapy for breast SCC.Material and methodsWe conducted a multicenter retrospective cohort study. Patients diagnosed with primary breast SCC who received adjuvant radiotherapy as part of their primary definitive treatment were included. Overall survival (OS), breast cancer-specific survival (BCSS), and recurrence-free interval (RFi) were evaluated.ResultsBetween January 2002 and December 2017, 25 breast SCC patients received adjuvant radiotherapy as a primary treatment were included. Median follow-up time was 43.5 months. Three (12%), fifteen (60%) and seven (28%) patients had clinical stage I, II and III disease, respectively. Fourteen patients underwent breast-conserving surgery and subsequent adjuvant radiotherapy. Eleven patients underwent mastectomy and post-mastectomy radiotherapy. Ten patients received regional lymph node irradiation. Nine (36%) patients had disease recurrence. The first site of recurrence was locoregional in five, but distant metastasis arose in one. Concurrent local and distant metastasis were seen in two. Six cases of local recurrence occurred within the irradiated site. Seven patients died, and six of the deaths were due to breast cancer. Five-year OS, BCSS, and Rfi were 69%, 70%, and 63%, respectively. In multivariate analysis, age and lymphatic invasion were associated with increased risk of recurrence.ConclusionBreast SCC has a high incidence of locoregional recurrence and poor prognosis. Age and lymphatic invasion are significant risk factors for recurrence.     

Outcomes according to treatment using an established protocol in patients with bilateral Wilms' tumor: A national Canadian population-based study

BackgroundBilateral Wilms tumor (BWT) is a rare entity. The goal of this study is to report outcomes (overall and event-free survival, OS/EFS) of BWT in a large cohort representative of the Canadian population since 2000. We focused on the occurrence of late events (relapse or death beyond 18 months), as well as outcomes of patients treated following the only protocol specifically designed for BWT to date, AREN0534, compared to patients treated following other therapeutic schemes.MethodsData was obtained for patients diagnosed with BWT between 2001 and 2018 from the Cancer in Young People in Canada (CYP-C) database. Demographics, treatment protocols, and dates for events were collected. Specifically, we examined outcomes of patients treated according to the Children's Oncology Group (COG) protocol AREN0534 since 2009. Survival analysis was performed.Results57/816 (7%) of patients with Wilms tumor had BWT during the study period. Median age at diagnosis was 2.74 years (IQR 1.37–4.48) and 35 (64%) were female; 8/57 (15%) had metastatic disease. After a median follow-up of 4.8 years (IQR 2.8–5.7 years, range 0.2–18 years), OS and EFS were 86% (CI 73–93%) and 80% (CI 66–89%), respectively. Less than 5 events were recorded after 18 months from diagnosis. Since 2009, patients treated according to the AREN0534 protocol had a statistically significant higher OS compared to patients treated with other protocols.ConclusionsIn this large Canadian cohort of patients with BWT, OS and EFS compared favorably to the published literature. Late events were rare. Patients treated according to a disease-specific protocol (AREN0534) had improved overall survival.Type of studyOriginal article.Level of evidenceLevel IV.     

Randomized phase II study to determine the optimal dose of 3-week cycle nab-paclitaxel in patients with metastatic breast cancer

BackgroundChemotherapy-induced peripheral neuropathy is commonly observed in patients treated with nanoparticle albumin–bound paclitaxel (nab-PTX). We conducted a multicenter randomized controlled study to evaluate the optimal dose of nab-PTX.MethodsWe compared three different doses of q3w nab-PTX (Standard: 260 mg/m² [SD260] vs Medium: 220 mg/m² [MD220] vs Low: 180 mg/m² [LD180]) in patients with HER2-negative metastatic breast cancer (MBC). Primary endpoint was progression-free survival (PFS). Grade 3/4 neuropathy rates in the three doses were estimated using the logistic regression model. The optimal dose was selected in two steps. Initially, if the hazard ratio (HR) for PFS was <0.75 or >1.33, the inferior dose was excluded, and we proceeded with the non-inferior dose. Then, if the estimated incidence rate of grade 3/4 neurotoxicity exceeded 10%, that dose was also excluded.ResultsOne hundred forty-one patients were randomly assigned to SD260 (n = 47), MD220 (n = 46), and LD180 (n = 48) groups, and their median PFS was 6.66, 7.34, and 6.82 months, respectively. The HRs were 0.73 (95% confidence interval [CI]: 0.42–1.28) in MD220 vs SD260, 0.77 (95% CI 0.47–1.28) in LD180 vs SD260, and 0.96 (95% CI 0.56–1.66) in LD180 vs MD220. SD260 was inferior to MD220 and was excluded. The estimated incidence rate of grade 3/4 neurotoxicity was 29.5% in SD260, 14.0% in MD220, and 5.9% in LD180. The final selected dose was LD180.ConclusionsIntravenous administration of low-dose nab-PTX at 180 mg/m² q3w may be the optimal therapy with meaningful efficacy and favorable toxicity in patients with MBC.     

Clinical characteristics and survival outcome of patients with estrogen receptor low positive breast cancer

BackgroundThe benefit of endocrine therapy for patients with estrogen receptor (ER)-low (1%–10%) positive breast cancer is a matter for debate. We aimed to compare the clinical characteristics and survival outcome of ER-low patients with ER-high (＞10%) positive patients and ER-negative patients.MethodsFrom the breast cancer database of our institution, we identified 5466 patients with known ER status who were diagnosed with early-stage breast cancer between January 2008 and December 2016. Variables associated with initiation of endocrine therapy were identified using multivariate logistic regression model. According to ER status, all patients were classified into ER-low (1%–10%), ER-high (>10%) and ER-negative subgroups. Fine and Gray competing risks regression was performed to compare the survival outcome of three subgroups.ResultsAge at diagnosis, ER status and progesterone receptor (PR) status were identified as correlates of initiation of endocrine therapy. ER-low patients were more likely to have advanced, PR-negative, human epidermal growth factor receptor 2 (HER2)-positive or grade Ⅲ disease compared to ER-high patients. Similar to ER-negative patients, ER-low patients presented increased rate of locoregional recurrence (LRR), distant recurrence (DR) and breast cancer mortality (BCM) than ER-high patients. Endocrine therapy showed nonsignificant trends toward lower LRR, DR and BCM in ER-low patients.ConclusionSimilar to ER-negative patients, ER-low patients had more aggressive clinical characteristics and worse survival outcome than ER-high patients. ER-low patients appeared to benefit less from endocrine therapy. Randomized studies are needed to further explore the endocrine responsiveness of ER-low patients.     

Evolving landscape of human epidermal growth factor receptor 2-positive breast cancer treatment and the future of biosimilars

Human epidermal growth factor receptor 2-positive (HER2+) breast cancer comprises approximately 15%–20% of all breast cancers and is associated with a poor prognosis. The introduction of anti-HER2 therapy has significantly improved clinical outcomes for patients with HER2+ breast cancer, and multiple HER2-directed agents (ie, trastuzumab, pertuzumab, lapatinib, and ado-trastuzumab emtansine [T-DM1]) are approved for clinical use in various settings. The treatment landscape for patients with HER2+ breast cancer is continuing to evolve. While novel agents and therapeutic strategies are emerging, biologic therapies, particularly trastuzumab, are likely to remain a mainstay of treatment. However, access issues create barriers to the use of biologics, and there is evidence for underuse of trastuzumab worldwide. A biosimilar is a biologic product that is highly similar to a licensed biologic in terms of product safety and effectiveness. Biosimilars of trastuzumab are in development and may soon become available. The introduction of biosimilars may improve access to anti-HER2 therapies by providing additional treatment options and lower-cost alternatives. Because HER2-targeted drugs may be administered for extended periods of time and in combination with other systemic therapies, biosimilars have the potential to result in significant savings for healthcare systems. Herein we review current and emerging treatment options for, and discuss the possible role of biosimilars in, treating patients with HER2+ breast cancer.     

Influence of age as a continuous variable on the prognosis of patients with pT1-2N1 breast cancer

PurposeTo assess the influence of age as a continuous variable on the prognosis of pT1-2N1 breast cancer and examine its decision-making value for postmastectomy radiotherapy (PMRT).MethodsWe retrospectively evaluated 5438 patients with pT1-2N1 breast cancer after mastectomy in 11 hospitals. A multivariable Cox proportional hazards regression model with penalized splines was used to examine the relationship between age and oncologic outcomes.ResultsThe median follow-up was 67.0 months. After adjustments for confounding characteristics, nonsignificant downward trend in locoregional recurrence (LRR) risk was observed with increasing age (P-non-linear association = 0.640; P-linear association = 0.078). A significant non-linear association was found between age and disease-free survival (DFS) and overall survival (OS) (P-non-linear association <0.05; P-linear association >0.05, respectively). The DFS and OS exhibited U-shaped relationships, with the hazard ratios (HRs), reaching a nadir at 50 years old. A decreased risk of LRR with PMRT vs. no PMRT (HR = 0.304, 95% CI: 0.204–0.454) was maintained in all ages. The HR of PMRT vs. no PMRT for DFS and OS gradually increased with age. In patients ≤50 years old, PMRT was independently associated with favorable LRR, DFS, and OS, all P < 0.05). In patients >50 years old, PMRT was independently associated with reduced LRR (P = 0.004), but had no effect on DFS or OS.ConclusionsAge was an independent prognostic factor for pT1-2N1 breast cancer; PMRT provided survival benefits for patients ≤50 years old, but not for patients >50 years old.     

Higher-risk breast cancer in women aged 80 and older: Exploring the effect of treatment on survival

BackgroundTo understand the association between various treatments and survival for older women with higher-risk breast cancer when controlling for patient and tumor factors.Materials and methodsWe conducted a retrospective, population-based study. Women aged 80 years or older and diagnosed between 2004 and 2017 with non-metastatic, higher-risk breast cancer were identified form the provincial cancer registry in Alberta, Canada. Higher-risk was defined as any of following: T3/4, node positive, human epidermal factor receptor-2 (Her2) positive or triple negative disease. Treatments were surgery, radiotherapy and systemic therapy (hormonal therapy, and/or chemotherapy and/or trastuzumab) or a combination of the previous. Cox regression models were used to examine the association between treatments and breast cancer specific survival (BCSS) and overall survival (OS).Results1369 patients were included. The median age was 84 years. 332 (24%) of women had T3-T4 tumors, 792 (58%) had nodal involvement, 130 (10%) had Her2 positive tumors, 124 (9%) had triple negative tumors. After a median follow-up of 35 months, 29.5% of patients died of breast cancer whereas 34.2% died from other causes. Patients had a lower adjusted hazard for BCSS if they had surgery (hazard ratio [HR] = 0.37 95% confidence interval [CI]: 0.27, 0.51), or systemic therapy (HR = 0.75, 95%CI: 0.58, 0.98). Patients had an increased probability of breast cancer death in the first 5 years after diagnosis compared to death from other causes.ConclusionsSurgery and systemic therapy were associated with longer BCSS and OS. This suggests that maximizing treatments might benefit higher-risk patients.