Background

Among patients with stage I breast cancer, there is significant uncertainty concerning the optimal threshold at which to consider chemotherapy, and when considered, there is controversy regarding whether to consider non-intensive versus intensive regimens. The authors examined the types and costs of adjuvant chemotherapy received among patients with stage I breast cancer.

Methods

The current study was a prospective cohort study including patients with stage I breast cancer who were treated at a National Comprehensive Cancer Network center from 2000 through 2009. Stage was defined according to the version of the American Joint Committee on Cancer Staging Manual applicable at the time of diagnosis. Stratifying by human epidermal growth factor receptor 2 (HER2), the authors examined the percentage of patients receiving intensive versus non-intensive chemotherapy regimens and the factors associated with type of chemotherapy administered using multivariable logistic regression. Costs of the most common regimens were estimated.

Results

Of 8907 patients, 33% received adjuvant chemotherapy. Among those individuals, there was an increase in the use of intensive chemotherapy within the last decade, from 31% in 2000 through 2005 to 63% in 2008 through 2009 (including an increase in the use of the combination of docetaxel, carboplatin, and trastuzumab) among patients with HER2-positive disease and from 15% in 2000 through 2005 to 41% in 2008 through 2009 among patients with HER2-negative disease (32% of patients with hormone receptor-positive and 59% of patients with triple-negative disease). Among patients treated with non-intensive regimens, there was an increase in the use of the combination of docetaxel and cyclophosphamide noted, with a decrease in the use of the doxorubicin and cyclophosphamide combination. The choice of regimen varied significantly by institution. The major drivers of cost variation were the incorporation of biologics (eg, trastuzumab) and growth factors, with significant variation even within non-intensive and intensive regimens.

Conclusions

Over time, there was an increase in use of intensive regimens among Stage I breast cancer, with striking institutional and cost variations.

Background

Understanding the impact of the tumor immune microenvironment and BRCA1/2-related DNA repair deficiencies on the clinical activity of immune checkpoint inhibitors may help optimize both patient and treatment selection in metastatic triple-negative breast cancer. In this substudy from the phase 3 IMpassion130 trial, immune biomarkers and BRCA1/2 alterations were evaluated for association with clinical benefit with atezolizumab and nab-paclitaxel (A+nP) vs placebo and nP in unresectable (P+nP) locally advanced or metastatic triple-negative breast cancer.

Methods

Patients were randomly assigned 1:1 to nab-paclitaxel 100 mg/m2 (days 1, 8, and 15 of a 28-day cycle) and atezolizumab 840 mg every 2 weeks or placebo until progression or toxicity. Progression-free survival and overall survival were evaluated based on programmed death-ligand 1 (PD-L1) expression on immune cells (IC) and tumor cells, intratumoral CD8, stromal tumor-infiltrating lymphocytes, and BRCA1/2 mutations.

Results

PD-L1 IC+ in either primary or metastatic tumor tissue was linked to progression-free survival and overall survival benefit with A+nP. PD-L1 IC+ low (26.9%; 243 of 902 patients) and high (13.9%; 125 of 902 patients) populations had improved outcomes that were comparable. Intratumoral CD8 and stromal tumor-infiltrating lymphocytes positivity (sTIL+) were associated with PD-L1 IC+ status; improved outcomes were observed with A+nP vs P+nP only in CD8+ and sTIL+ patients who were also PD-L1 IC+. BRCA1/2 mutations (occurring in 14.5% [89 of 612 patients]) were not associated with PD-L1 IC status, and PD-L1 IC+ patients benefited from A+nP regardless of BRCA1/2 mutation status.

Conclusions

Although A+nP was more efficacious in patients with richer tumor immune microenvironment, clinical benefit was only observed in patients whose tumors were PD-L1 IC+.

Purpose

We compared nab-paclitaxel or ixabepilone once per week to paclitaxel with bevacizumab as first-line therapy for patients with advanced breast cancer (BC) to evaluate progression-free survival (PFS) for nab-paclitaxel or ixabepilone versus paclitaxel.

Patients and methods

Eligible patients were age ≥ 18 years with chemotherapy-naive advanced BC. Patients were randomly assigned to bevacizumab with paclitaxel 90 mg/m(2) (arm A), nab-paclitaxel 150 mg/m(2) (arm B), or ixabepilone 16 mg/m(2) (arm C), once per week for 3 of 4 weeks. Planned enrollment was 900 patients, which would give 88% power to detect a hazard ratio of 0.73.

Results

In all, 799 patients were enrolled, and 783 received treatment (97% received bevacizumab). Arm C was closed for futility at the first interim analysis (n = 241), and arm A (n = 267) and arm B (n = 275) were closed for futility at the second interim analysis. Median PFS for paclitaxel was 11 months, ixabepilone was inferior to paclitaxel (PFS, 7.4 months; hazard ratio, 1.59; 95% CI, 1.31 to 1.93; P < .001), and nab-paclitaxel was not superior to paclitaxel (PFS, 9.3 months; hazard ratio, 1.20; 95% CI, 1.00 to 1.45; P = .054). Results were concordant with overall survival; time to treatment failure was significantly shorter in both experimental arms v paclitaxel. Hematologic and nonhematologic toxicity, including peripheral neuropathy, was increased with nab-paclitaxel, with more frequent and earlier dose reductions.

Conclusion

In patients with chemotherapy-naive advanced BC, ixabepilone once per week was inferior to paclitaxel, and nab-paclitaxel was not superior with a trend toward inferiority. Toxicity was increased in the experimental arms, particularly for nab-paclitaxel. Paclitaxel once per week remains the preferred palliative chemotherapy in this setting.

Purpose

Treatment decisions for patients with T1a,bN0M0 breast cancer are challenging. We studied the time trends in use of adjuvant chemotherapy and survival outcomes among these patients.

Patients and methods

This was a prospective cohort study within the National Comprehensive Cancer Network Database that included 4,113 women with T1a,bN0M0 breast cancer treated between 2000 and 2009. Tumors were grouped by size (T1a, T1b), biologic subtype defined by hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status, and receipt of chemotherapy with or without trastuzumab.

Results

Median follow-up time was 5.5 years. Eight percent of patients with HR-positive/HER2-negative tumors were treated with chemotherapy. Fifty-two percent of those with HER2-positive or HR-negative/HER2-negative breast cancers received chemotherapy, with an increase over the last decade. Survival outcomes diverged by subtype and size, but the 5-year distant relapse-free survival (DRFS) did not exceed 10% in any subgroup. The 5-year DRFS for patients with T1a tumors untreated with chemotherapy ranged from 93% to 98% (n = 49 to 972), and for patients with T1b tumors, it ranged from 90% to 96% (n = 17 to 2,005). Patients with HR-positive/HER2-negative disease had the best DRFS estimates, and patients with HR-negative/HER2-negative tumors had the lowest. In this observational, nonrandomized cohort study, the 5-year DRFS for treated patients with T1a tumors was 100% for all subgroups (n = 12 to 33), and for patients with T1b tumors, it ranged from 94% to 96% (n = 88 to 241).

Conclusion

Women with T1a,b tumors have an excellent prognosis without chemotherapy. Size and tumor subtype may identify patients in whom the rate of recurrence justifies consideration of chemotherapy. These patients represent an optimal group for evaluating less toxic adjuvant regimens to maintain efficacy while minimizing short- and long-term risks.

PURPOSE: Sensory peripheral neuropathy is a common and sometimes debilitating toxicity associated with paclitaxel therapy. This study aims to identify genetic risk factors for the development of this toxicity. EXPERIMENTAL DESIGN: A prospective pharmacogenetic analysis of patients with primary breast cancer, randomized to the paclitaxel arm of CALGB 40101, was used to identify genetic predictors of the onset and severity of sensory peripheral neuropathy. A genome-wide association study in 855 subjects of European ancestry was conducted and findings were replicated in additional European (n = 154) and African American (n = 117) subjects. RESULTS: A single nucleotide polymorphism in FGD4 was associated with the onset of sensory peripheral neuropathy in the discovery cohort [rs10771973; HR, 1.57; 95% confidence interval (CI), 1.30-1.91; P = 2.6 × 10(-6)] and in a European (HR, 1.72; 95% CI, 1.06-2.80; P = 0.013) and African American (HR, 1.93; 95% CI, 1.13-3.28; P = 6.7 × 10(-3)) replication cohort. There is also evidence that markers in additional genes, including EPHA5 (rs7349683) and FZD3 (rs10771973), were associated with the onset or severity of paclitaxel-induced sensory peripheral neuropathy. CONCLUSIONS: A genome-wide association study has identified novel genetic markers of paclitaxel-induced sensory peripheral neuropathy, including a common polymorphism in FGD4, a congenital peripheral neuropathy gene. These findings suggest that genetic variation may contribute to variation in development of this toxicity. Validation of these findings may allow for the identification of patients at increased risk of peripheral neuropathy and inform the use of an alternative to paclitaxel and/or the clinical management of this toxicity.

Purpose

We evaluated the prognostic and predictive value of circulating tumor cells (CTCs) hormone receptor-positive (HR⁺) metastatic breast cancer (MBC) patients randomized to letrozole alone or letrozole plus bevacizumab in the first-line setting (CALGB 40503).

Experimental design

Blood samples were collected at pretreatment and three additional time points during therapy. The presence of ≥5 CTCs per 7.5 mL of blood was considered CTC positive. Association of CTCs with progression-free survival (PFS) and overall survival (OS) was assessed using Cox regression models.

Results

Of 343 patients treated, 294 had CTC data and were included in this analysis. Median follow-up was 39 months. In multivariable analysis, CTC-positive patients at baseline (31%) had significantly reduced PFS [HR, 1.49; 95% confidence interval (CI), 1.12-1.97] and OS (HR, 2.08; 95% CI, 1.49-2.93) compared with CTC negative. Failure to clear CTCs during treatment was associated with significantly increased risk of progression (HR, 2.2; 95% CI, 1.58-3.07) and death (HR, 3.4; 95% CI, 2.36-4.88). CTC-positive patients who received only letrozole had the worse PFS (HR, 2.3; 95% CI, 1.54-3.47) and OS (HR, 2.6; 95% CI, 1.59-4.40). Median PFS in CTC-positive patients was significantly longer (18.0 vs. 7.0 months) in letrozole plus bevacizumab versus letrozole arm (P = 0.0009). Restricted mean survival time analysis further revealed that addition of bevacizumab was associated with PFS benefit in both CTC-positive and CTC-negative patients, but OS benefit was only observed in CTC-positive patients.

Conclusions

CTCs were highly prognostic for the addition of bevacizumab to first-line letrozole in patients with HR+ MBC in CALGB 40503. Further research to determine the potential predictive value of CTCs in this setting is warranted.

Purpose

To investigate whether anti-vascular endothelial growth factor therapy with bevacizumab prolongs progression-free survival (PFS) when added to first-line letrozole as treatment of hormone receptor-positive metastatic breast cancer (MBC).

Patients and methods

Women with hormone receptor-positive MBC were randomly assigned 1:1 in a multicenter, open-label, phase III trial of letrozole (2.5 mg orally per day) with or without bevacizumab (15 mg/kg intravenously once every 3 weeks) within strata defined by measurable disease and disease-free interval. This trial had 90% power to detect a 50% improvement in median PFS from 6 to 9 months. Using a one-sided α = .025, a target sample size of 352 patients was planned.

Results

From May 2008 to November 2011, 350 women were recruited; 343 received treatment and were observed for efficacy and safety. Median age was 58 years (range, 25 to 87 years). Sixty-two percent had measurable disease, and 45% had de novo MBC. At a median follow-up of 39 months, the addition of bevacizumab resulted in a significant reduction in the hazard of progression (hazard ratio, 0.75; 95% CI, 0.59 to 0.96; P = .016) and a prolongation in median PFS from 15.6 months with letrozole to 20.2 months with letrozole plus bevacizumab. There was no significant difference in overall survival (hazard ratio, 0.87; 95% CI, 0.65 to 1.18; P = .188), with median overall survival of 43.9 months with letrozole versus 47.2 months with letrozole plus bevacizumab. The largest increases in incidence of grade 3 to 4 treatment-related toxicities with the addition of bevacizumab were hypertension (24% v 2%) and proteinuria (11% v 0%).

Conclusion

The addition of bevacizumab to letrozole improved PFS in hormone receptor-positive MBC, but this benefit was associated with a markedly increased risk of grade 3 to 4 toxicities. Research on predictive markers will be required to clarify the role of bevacizumab in this setting.

IMPORTANCE: Trastuzumab is a life-saving therapy but is associated with symptomatic and asymptomatic left ventricular ejection fraction (LVEF) decline. We report the cardiac toxic effects of a nonanthracycline and trastuzumab-based treatment for patients with early-stage human epidermal growth factor receptor 2 (ERBB2, formerly HER2 or HER2/neu)-positive breast cancer. OBJECTIVE: To determine the cardiac safety of paclitaxel with trastuzumab and the utility of LVEF monitoring in patients with node-negative, ERBB2-positive breast cancer. DESIGN, SETTING, AND PARTICIPANTS: In this secondary analysis of an uncontrolled, single group study across 14 medical centers, enrollment of 406 patients with node-negative, ERBB2-positive breast cancer 3 cm, or smaller, and baseline LVEF of greater than or equal to 50% occurred from October 9, 2007, to September 3, 2010. Patients with a micrometastasis in a lymph node were later allowed with a study amendment. Median patient age was 55 years, 118 (29%) had hypertension, and 30 (7%) had diabetes. Patients received adjuvant paclitaxel for 12 weeks with trastuzumab, and trastuzumab was continued for 1 year. Median follow-up was 4 years. INTERVENTIONS: Treatment consisted of weekly 80-mg/m2 doses of paclitaxel administered concurrently with trastuzumab intravenously for 12 weeks, followed by trastuzumab monotherapy for 39 weeks. During the monotherapy phase, trastuzumab could be administered weekly 2-mg/kg or every 3 weeks as 6-mg/kg. Radiation and hormone therapy were administered per standard guidelines after completion of the 12 weeks of chemotherapy. Patient LVEF was assessed at baseline, 12 weeks, 6 months, and 1 year. MAIN OUTCOMES AND MEASURES: Cardiac safety data, including grade 3 to 4 left ventricular systolic dysfunction (LVSD) and significant asymptomatic LVEF decline, as defined by our study, were reported. RESULTS: Overall, 2 patients (0.5%) (95% CI, 0.1%-1.8%) developed grade 3 LVSD and came off study, and 13 (3.2%) (95% CI, 1.9%-5.4%) had significant asymptomatic LVEF decline, 11 of whom completed study treatment. Median LVEF at baseline was 65%; 12 weeks, 64%; 6 months, 64%; and 1 year, 64%. CONCLUSIONS AND RELEVANCE: Cardiac toxic effects from paclitaxel with trastuzumab, manifesting as grade 3 or 4 LVSD or asymptomatic LVEF decline, were low. Patient LVEF was assessed at baseline, 12 weeks, 6 months, and 1 year, and our findings suggest that LVEF monitoring during trastuzumab therapy without anthracyclines could be simplified for many individuals.

Purpose

Primary endocrine therapy for ductal carcinoma in situ (DCIS) as a potential alternative to surgery has been understudied. This trial explored the feasibility of a short-term course of letrozole and sought to determine whether treatment results in measurable radiographic and biologic changes in estrogen receptor (ER)-positive DCIS.

Patients and methods

A phase II single-arm multicenter cooperative-group trial was conducted in postmenopausal patients diagnosed with ER-positive DCIS without invasion. Patients were treated with letrozole 2.5 mg per day for 6 months before surgery. Breast magnetic resonance imaging (MRI) was obtained at baseline, 3 months, and 6 months. The primary end point was change in 6-month MRI enhancement volume compared with baseline.

Results

Overall, 79 patients were enrolled and 70 completed 6 months of letrozole. Of these, 67 patients had MRI data available for each timepoint. Baseline MRI volumes ranged from 0.004 to 26.3 cm³. Median reductions from baseline MRI volume (1.4 cm³) were 0.6 cm³ (61.0%) at 3 months (P < .001) and 0.8 cm³ (71.7%) at 6 months (P < .001). Consistent reductions were seen in median baseline ER H-score (228; median reduction, 15.0; P = .005), progesterone receptor H-score (15; median reduction, 85.0; P < .001), and Ki67 score (12%; median reduction, 6.3%; P = .007). Of the 59 patients who underwent surgery per study protocol, persistent DCIS remained in 50 patients (85%), invasive cancer was detected in six patients (10%), and no residual DCIS or invasive cancer was seen in nine patients (15%).

Conclusions

In a cohort of postmenopausal women with ER-positive DCIS, preoperative letrozole resulted in significant imaging and biomarker changes. These findings support future trials of extended endocrine therapy as primary nonoperative treatment of some DCIS.

Background

No single standard treatment exists for patients with small, node-negative, human epidermal growth factor receptor type 2 (HER2)-positive breast cancers, because most of these patients have been ineligible for the pivotal trials of adjuvant trastuzumab.

Methods

We performed an uncontrolled, single-group, multicenter, investigator-initiated study of adjuvant paclitaxel and trastuzumab in 406 patients with tumors measuring up to 3 cm in greatest dimension. Patients received weekly treatment with paclitaxel and trastuzumab for 12 weeks, followed by 9 months of trastuzumab monotherapy. The primary end point was survival free from invasive disease.

Results

The median follow-up period was 4.0 years. The 3-year rate of survival free from invasive disease was 98.7% (95% confidence interval [CI], 97.6 to 99.8). Among the 12 relapses seen, 2 were due to distant metastatic breast cancer. Excluding contralateral HER2-negative breast cancers and nonbreast cancers, 7 disease-specific events were noted. A total of 13 patients (3.2%; 95% CI, 1.7 to 5.4) reported at least one episode of grade 3 neuropathy, and 2 had symptomatic congestive heart failure (0.5%; 95% CI, 0.1 to 1.8), both of whom had normalization of the left ventricular ejection fraction after discontinuation of trastuzumab. A total of 13 patients had significant asymptomatic declines in ejection fraction (3.2%; 95% CI, 1.7 to 5.4), as defined by the study, but 11 of these patients were able to resume trastuzumab therapy after a brief interruption.

Conclusions

Among women with predominantly stage I HER2-positive breast cancer, treatment with adjuvant paclitaxel plus trastuzumab was associated with a risk of early recurrence of about 2%; 6% of patients withdrew from the study because of protocol-specified adverse events. (Funded by Genentech; ClinicalTrials.gov number, NCT00542451.).