Long-term hazard of recurrence in HER2+ breast cancer patients untreated with anti-HER2 therapy

Introduction

Worldwide, many patients with HER2+ (human epidermal growth factor receptor 2-positive) early breast cancer (BC) do not receive adjuvant trastuzumab. Hazards of recurrence of these patients with respect to hormone receptor status of the primary tumor have not been described.

Methods

Using data from 1,260 patients randomized to placebo in the adjuvant TEACH trial, we report 10-year annual hazards of recurrence in HER2+ patients not treated with anti-HER2 therapy.

Results

Disease-free survival (DFS) was 75% after 5 and 61% after 10 years, respectively. Patients with HER2+ hormone receptor-positive (HR+ (hormone receptor-positive); ER+ (estrogen receptor-positive) or PR+ (progesterone receptor-positive)) disease had a significantly better DFS than patients with HER2+ HR- (ER-/PR-) disease (hazard ratio 0.72, P = 0.02). This difference was explainable by a significantly higher hazard of recurrence in years 1 to 5 in HER2+ HR- compared to HER2+ HR+ patients, with a mean risk of recurrence of 9%/year for HR- versus 5%/year in HR+ patients (hazard ratio 0.59, P = 0.002 for years 1 to 5). The high early risk of recurrence of HER2+ HR- patients declined sharply over time, so that it was similar to that seen in HER2+ HR+ patients in years 6 to 10 (hazard ratio 0.97, P = 0.92 for years 6 to 10).

Conclusions

Our results show that outcomes in HER2+ patients with early BC not receiving anti-HER2 therapy strongly depend on HR expression. The very high early risk of relapse seen in HER2+ HR- patients is particularly relevant in health care settings with limited access to adjuvant anti-HER2 treatment. The event rates shown for subpopulations of HER2+ BC patients suggest that in resource-constrained environments patients with HER2+ HR- early BC should be prioritized for consideration of adjuvant anti-HER2 therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-015-0568-1) contains supplementary material, which is available to authorized users.     

Local-regional control according to surrogate markers of breast cancer subtypes and response to neoadjuvant chemotherapy in breast cancer patients undergoing breast conserving therapy

Introduction

Breast cancers of different molecular subtypes have different survival rates. The goal of this study was to identify patients at high risk for local-regional recurrence according to response to neoadjuvant chemotherapy and surrogate markers of molecular subtypes in patients undergoing breast conserving therapy (BCT).

Methods

Clinicopathologic data from 595 breast cancer patients who received neoadjuvant chemotherapy and BCT from 1997 to 2005 were identified. Estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) expression determined by immunohistochemistry were used to construct the following subtypes: ER+ or PR+ and HER2- (hormone receptor (HR)+/HER2-; 52%), ER+ or PR+ and HER2+ (HR+/HER2+; 9%), ER- and PR- and HER2+ (HR-/HER2+; 7%) and ER- and PR- and HER2- (HR-/HER2-; 32%). Actuarial rates were calculated using the Kaplan-Meier method and compared using the log-rank test. Cox proportional hazards models were used for multivariate analysis (MVA).

Results

After a median follow-up of 64 months, the five-year local-regional recurrence (LRR)-free survival rate for all patients was 93.8%. The five-year LRR-free survival rates varied by subtype: HR+/HER2- 97.0%, HR+/HER2+ 95.9%, HR-/HER2+ 86.5% and HR-/HER2- 89.5% (P = 0.001). In addition to subtype, clinical stage III disease (90% vs. 95% for I/II, P = 0.05), high nuclear grade (92% vs. 97% with low/intermediate grade, P = 0.03), presence of lymphovascular invasion (LVI) (89% vs. 95% in those without LVI, P = 0.02) and four or more positive lymph nodes on pathologic examination (87% vs. 95% with zero to three positive lymph nodes, P = 0.03) were associated with lower five-year LRR-free survival on univariate analysis. On MVA, HR-/HER2+ and HR-/HER2- subtypes and disease in four or more lymph nodes were associated with decreased LRR-free survival. A pathologic complete response (pCR) was associated with improved LRR-free survival.

Conclusions

Patients with HR+/HER2- and HR+/HER2+ subtypes had excellent LRR-free survival regardless of tumor response to neoadjuvant chemotherapy. Patients with HR-/HER2+ and HR-/HER2- subtypes with poor response to neoadjuvant chemotherapy had worse LRR-free survival after BCT. Additional study is needed to determine the impact of trastuzumab on local-regional control in HER2+ tumors. Our data suggest that patients with HR-/HER2- subtype tumors not achieving pCR may benefit from novel strategies to improve local-regional control.     

Breast Cancer Subtype as a Predictor of Lymph Node Metastasis according to the SEER Registry

Purpose

Breast cancer subtype correlates with response to systemic therapy and overall survival (OS), but its impact on lymphatic spread is incompletely understood. In this study, we used the Surveillance, Epidemiology, and End Results registry to assess whether the subtype can predict the presence of nodal metastasis or advanced nodal stage in breast cancer.

Methods

A total of 7,274 eligible patients diagnosed with T1-3 infiltrating ductal carcinoma with known estrogen or progesterone hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status, who underwent surgical excision of the primary tumor and pathologic lymph node evaluation, were included in this analysis. Patients were categorized into four breast cancer subtypes: HR+/HER2-; HR+/HER2+; HR-/HER2+; and HR-/HER2-. Binary logistic regression analysis was used to determine whether breast cancer subtype, tumor size, tumor grade, patient race, and patient age at diagnosis are independently predictive of lymph node positivity or advanced nodal stage. The Pearson chi-square test was used to determine whether progesterone receptor (PR) status had an impact on the incidence of lymph node positivity in estrogen receptor (ER) positive patients.

Results

Independent predictors of nodal positivity included breast cancer subtype (p=0.040), tumor size (p<0.001), tumor grade (p<0.001), and patient age (p<0.001), whereas only tumor size (p<0.001), grade (p=0.001), and patient age (p=0.005) predicted advanced nodal stage. Triple-negative cancers had a significantly lower risk of nodal positivity than the HR+/HER2- subtype (odds ratio, 0.686; p=0.004), but no other significant differences between subtypes were observed. There was also no difference in lymph node positivity between PR+ and PR- tumors amongst ER+/HER2- (p=0.228) or ER+/HER2+ tumors (p=0.713).

Conclusion

The HR+/HER2-breast cancer subtype has a higher rate of lymph node involvement at diagnosis than the triple-negative subtype. These findings may play a role in guiding regional management considerations if confirmed in further studies.     

Effect Modification of Hormonal Therapy by p53 Status in Invasive Breast Cancer

Purpose

We aimed to confirm the prognostic and predictive value of p53 expression, particularly in invasive breast cancer patients, according to immunohistochemical hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status.

Methods

Immunohistochemical data for p53, estrogen receptor, progesterone receptor, and HER2 expression from a total of 15,598 patients were retrospectively retrieved from the web-based database of the Korean Breast Cancer Society. Overall survival (OS) and breast cancer-specific survival (BCSS) were calculated and compared using the Kaplan-Meier method and log-rank test, respectively. Multivariate analyses were performed using a stratified Cox proportional hazard regression model. A model evaluating interactions between p53 expression and both hormonal therapy and chemotherapy was used to determine the treatment benefit from both modalities.

Results

The prognostic value of p53 for OS and BCSS was most significant in the HR+/HER2- subgroup, with hazard ratios of 1.44 (95% confidence interval [CI], 1.08-1.93) and 1.47 (95% CI, 1.09-1.99), respectively. The p53 overexpression hazard ratios were of borderline significance for the HR+/HER2+ subgroup and were not significant for the HR-/HER2+ and HR-/HER2- subgroups. The model with interaction terms revealed that hormonal therapy significantly interacts with p53 status (p=0.002 and p=0.007 for OS and BCSS, respectively), suggesting an insignificant prognostic value for p53 status (p=0.268 and p=0.296 for OS and BCSS, respectively). An interaction between chemotherapy and p53 status was not found in this model.

Conclusion

p53 overexpression has independent prognostic value, particularly in cases of HR+/HER2- invasive breast cancer, which may be due to effect modification of hormonal therapy dependent on p53 status.     

Association between HER2 status and response to neoadjuvant anthracycline followed by paclitaxel plus carboplatin chemotherapy without trastuzumab in breast cancer

Background

We recently showed HER2-positive breast cancers are less likely to respond to neoadjuvant anthracycline chemotherapy. Here, we investigated whether HER2-positive breast cancers responded to sequential neoadjuvant anthracycline followed by paclitaxel plus carboplatin regimen in the absence of trastuzumab.

Methods

Women (n=372) with operable primary breast cancer initially received two cycles of neoadjuvant anthracyclines, the clinical tumor response was assessed, then patients were received four cycles of paclitaxel plus carboplatin regimen. All the patients did not received trastuzumab treatment in the neoadjuvant setting. HER2 status was determined by immunohistochemistry and/or by fluorescence in situ hybridization in core-biopsy breast cancer tissue obtained before the neoadjuvant chemotherapy.

Results

Eighteen percent (67/372) of patients achieved a pathologic complete response (pCR) in their breast. HER2-positive tumors had a significant higher pCR rate than HER2-negative tumors (33.0% versus 13.5%, P<0.001) in this cohort of 372 patients, and positive HER2 status remained an independent favorable predictor of pCR in a multivariate analysis [odds ratio (OR), 2.26; 95% confidence interval (CI), 1.18 to 4.36, P=0.015]. Furthermore, patients who responded to initial anthracycline regimens were more likely to respond to paclitaxel plus carboplatin than patients who did not (pCR, 27.2% versus 14.6%, P=0.005). Patients with HER2-positive tumors exhibited a significant higher pCR rate than did patients with HER2-negative tumors in both anthracycline response group (40.5% versus 20.0%, P=0.025) and anthracycline non-response group (28.3% versus 11.3%, P=0.002).

Conclusions

Under the circumstance of no trastuzumab treatment, women with HER2-positive cancers derive a large benefit from paclitaxel-carboplatin-based neoadjuvant chemotherapy.     

Implications of constructed biologic subtype and its relationship to locoregional recurrence following mastectomy

Introduction

We examined the prognostic value of biologic subtype on locoregional recurrence (LRR) after mastectomy in a cohort of low risk women who did not receive adjuvant radiation therapy.

Methods

A total of 819 patients with invasive breast cancer underwent mastectomy from January 2000 through December 2005. No patient received preoperative chemotherapy. Estrogen receptor (ER) receptor, progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) status were used to construct the following 4 subtypes: i) ER+ or PR+ and HER2- (HR+/HER2-), ii) ER+ or PR+ and HER2+ (HR+/HER2+), iii) ER- and PR- and HER2+ (HR-/HER2+)and iv) ER- and PR- and HER2- (HR-/HER2-). LRR-free survival was estimated by the Kaplan-Meier method. Cox proportional hazard models were used to evaluate the association between time-to-event outcomes and patient prognostic factors.

Results

At a median follow-up of 58 months, five-year cumulative incidence of LRR for the entire cohort was 2.5%. Subtype specific LRR rates were 1% for HR+/HER2-, 6.5% in HR+/HER2+, 2% for HR-/HER2+ and 10.9% for HR-/HER2- (P < 0.01). In HER-2+ patients (irrespective of ER/PR status), trastuzumab therapy was not associated with LRR-free survival. On multivariate analysis, one to three positive lymph nodes (HR 4.75 (confidence interval (CI) 1.75 to 12.88, P < 0.01), ?? 4 positive lymph nodes (HR23.4 (CI 4.64 to 117.94, P < 0.01), HR+/HER2+ (HR 4.26 (CI 1.05 to 17.33), P = 0.04), and HR-/HER2- phenotype (HR 13.87 (CI 4.96 to 38.80), P < 0.01) were associated with shorter LRR-free survival whereas age > 50 at diagnosis (HR 0.31 (CI 0.12 to 0.80), P = 0.02) was associated with improved LRR-free survival. Among the HR-/HER2- subtypes, five-year LRR incidence was 23.4% in patients with positive lymph nodes compared to 7.8% for lymph node negative patients (P = 0.01), although this association did not reach significance when the analysis was limited to HR-/HER2- women with only one to three positive lymph nodes (15.6% versus 7.8%, P = 0.11).

Conclusions

Constructed subtype is a prognostic factor for LRR after mastectomy among low risk women not receiving adjuvant radiation therapy, although rates of LRR remain low across subtypes. Patients with node positive, HR-/HER2- type tumors were more likely to experience LRR following mastectomy alone. Prospective studies to further investigate the potential benefit of adjuvant radiation therapy in these women are warranted.     

HER2 and ESR1 mRNA expression levels and response to neoadjuvant trastuzumab plus chemotherapy in patients with primary breast cancer

Introduction

Recent data suggest that benefit from trastuzumab and chemotherapy might be related to expression of HER2 and estrogen receptor (ESR1). Therefore, we investigated HER2 and ESR1 mRNA levels in core biopsies of HER2-positive breast carcinomas from patients treated within the neoadjuvant GeparQuattro trial.

Methods

HER2 levels were centrally analyzed by immunohistochemistry (IHC), silver in situ hybridization (SISH) and qRT-PCR in 217 pretherapeutic formalin-fixed, paraffin-embedded (FFPE) core biopsies. All tumors had been HER2-positive by local pathology and had been treated with neoadjuvant trastuzumab/ chemotherapy in GeparQuattro.

Results

Only 73% of the tumors (158 of 217) were centrally HER2-positive (cHER2-positive) by IHC/SISH, with cHER2-positive tumors showing a significantly higher pCR rate (46.8% vs. 20.3%, P <0.0005). HER2 status by qRT-PCR showed a concordance of 88.5% with the central IHC/SISH status, with a low pCR rate in those tumors that were HER2-negative by mRNA analysis (21.1% vs. 49.6%, P <0.0005). The level of HER2 mRNA expression was linked to response rate in ESR1-positive tumors, but not in ESR1-negative tumors. HER2 mRNA expression was significantly associated with pCR in the HER2-positive/ESR1-positive tumors (P = 0.004), but not in HER2-positive/ESR1-negative tumors.

Conclusions

Only patients with cHER2-positive tumors - irrespective of the method used - have an increased pCR rate with trastuzumab plus chemotherapy. In patients with cHER2-negative tumors the pCR rate is comparable to the pCR rate in the non-trastuzumab treated HER-negative population. Response to trastuzumab is correlated to HER2 mRNA levels only in ESR1-positive tumors. This study adds further evidence to the different biology of both subsets within the HER2-positive group.Introduction The human epidermal growth factor receptor 2 (HER2) is the prototype of a predictive biomarker for targeted treatment [1-8]. International initiatives have established the combination of immunohistochemistry (IHC) and in situ hybridization as the current gold standard [9,10]. As an additional approach determination of HER2 mRNA expression is technically feasible in formalin-fixed paraffin-embedded (FFPE) tissue [11-13]. Crosstalk between the estrogen receptor (ER) and the HER2 pathway has been suggested based on cell culture and animal models [14]. Consequently, the 2011 St Gallen panel has pointed out that HER2-positive tumors should be divided into two groups based on expression of the ER [15].A retrospective analysis of the National Surgical Adjuvant Breast and Bowel Project (NSABP) B31 study has suggested that mRNA levels of HER2 and ESR1 might be relevant for the degree of benefit from adjuvant trastuzumab. By subpopulation treatment effect pattern plot (STEPP) analysis in ER-positive tumors, benefit from trastuzumab was shown to be restricted to those with higher levels of HER2 mRNA (S Paik, personal communication, results summarized in [15]).In our study we evaluated this hypothesis in the neoadjuvant setting in a cohort of 217 patients from the neoadjuvant GeparQuattro trial [5]. All patients had been HER2- positive by local pathology assessment and had received 24 to 36 weeks of neoadjuvant trastuzumab plus an anthracycline/taxane-based chemotherapy. For central evaluation we used three different methods, HER2 IHC, and HER2 silver in situ hybridization (SISH), as well as measurement of HER2 mRNA by quantitative real-time (qRT)-PCR [11].The primary objective of this analysis was to investigate if pathological complete response (pCR) rate in HER2-positive breast cancer would depend on the level of HER2 mRNA expression, with a separate analysis for HR-positive and -negative tumors. Central evaluation of the HER2 status showed that 27% of the tumors with HER2 overexpression by local pathology were HER2-negative. This enabled us to compare response rates in patients with HER2-positive and -negative tumors as a secondary objective.     

Tumor histological subtyping determined by hormone receptors and HER2 status defines different pathological complete response and outcome to dose-dense neoadjuvant chemotherapy in breast cancer patients

Purpose

To assess the impact in pathological complete response (pCR) and outcome of two dose-dense neoadjuvant chemotherapy (DDNC) regimens among different histological subtypes determined by hormonal receptor (HR) and HER2 status in breast cancer patients.

Methods

A total of 127 breast cancer patients were treated with DDNC in two prospective studies. A: adriamycin 40 mg/m² on day (d) 1 plus paclitaxel 150 mg/m² and gemcitabine 2,000 mg/m² on d2 for six cycles (n = 54). B: epirubicin 90 mg/m², cyclophosphamide 600 mg/m² on d1 for three cycles, followed by paclitaxel 150 mg/m² and gemcitabine 2,500 mg/m² on d1 ± trastuzumab according to HER2 status (n = 73). Histological subtypes of breast cancer were 49 % HR+/HER2?, 17.5 % HR+/HER2+, 13.5 % HR?/HER2+ and 20 % HR?/HER2?.

Results

pCR (absence of invasive cells in breast and lymph node) was achieved in 35 patients (28 %). The pCR rate was significantly different between histological subtypes: HR+/HER2? (9 %), HR+/HER2+ (23 %), HR?/HER2+ (50 %), HR?/HER2? (56 %) (p < 0.001). The median follow-up was 81 months (r: 15–150 months). HR?/HER2? tumor subtype had a significantly worse DFS compared to HR+/HER2? (p = 0.02), RH+/HER2+ (p = 0.04) and HR?/HER2+ tumor subtypes (p = 0.02). HR?/HER2? tumor subtype had a significantly shorter OS compared to HR+/HER2? (p = 0.007), RH+/HER2+ (p = 0.05), and HR?/HER2+ (p = 0.03) tumor subtypes. However, no significant difference was observed in DFS and OS among HR?/HER2? tumors that achieved a pCR.

Conclusions

HR?/HER2? and HR?/HER2+ subtypes had a high pCR rate to DDNC. HR?/HER2? tumors had a worse outcome compared to other tumor subtypes but no significant difference was observed among HR?/HER2? tumors that achieved a pCR.     

Impact of hormone receptor status on patterns of recurrence and clinical outcomes among patients with human epidermal growth factor-2-positive breast cancer in the National Comprehensive Cancer Network: a prospective cohort study

Introduction

In gene expression experiments, hormone receptor (HR)-positive/human epidermal growth factor-2 (HER2)-positive tumors generally cluster within the luminal B subset; whereas HR-negative/HER2-positive tumors reside in the HER2-enriched subset. We investigated whether the clinical behavior of HER2-positive tumors differs by HR status.

Methods

We evaluated 3,394 patients who presented to National Comprehensive Cancer Network (NCCN) centers with stage I to III HER2-positive breast cancer between 2000 and 2007. Tumors were grouped as HR-positive/HER2-positive (HR+/HER2+) or HR-negative/HER2-positive (HR-/HER2+). Chi-square, logistic regression and Cox hazard proportional regression were used to compare groups.

Results

Median follow-up was four years. Patients with HR-/HER2+ tumors (n = 1,379, 41% of total) were more likely than those with HR+/HER-2+ disease (n = 2,015, 59% of total) to present with high histologic grade and higher stages (P <0.001). Recurrences were recorded for 458 patients. HR-/HER2+ patients were less likely to experience first recurrence in bone (univariate Odds Ratio (OR) = 0.53, 95% Confidence Interval (CI): 0.34 to 0.82, P = 0.005) and more likely to recur in brain (univariate OR = 1.75, 95% CI: 1.05 to 2.93, P = 0.033). A lower risk of recurrence in bone persisted after adjusting for age, stage and adjuvant trastuzumab therapy (OR = 0.53, 95% CI: 0.34 to 0.83, P = 0.005) and when first and subsequent sites of recurrence were both considered (multivariable OR = 0.55, 95% CI: 0.37 to 0.80, P = 0.002). As compared with patients with HR+/HER2+ disease, those with HR-/HER2+ disease had significantly increased hazard of early, but not late, death (hazard ratio of death zero to two years after diagnosis = 1.92, 95% CI: 1.28 to 2.86, P = 0.002, hazard ratio of death two to five years after diagnosis = 1.55, 95% CI: 1.19 to 2.00, P = 0.001; hazard ratio of death more than five years after diagnosis = 0.81, 95% CI: 0.55 to 1.19, P = 0.285, adjusting for age, race/ethnicity, stage at diagnosis, grade and year of diagnosis).

Conclusions

Presenting features, patterns of recurrence and survival of HER2-positive breast cancer differed by HR status. These differences should be further explored and integrated in the design of clinical trials.     

Predictors of recurrence in breast cancer patients with a pathologic complete response after neoadjuvant chemotherapy

Background:

Although a pathologic complete response (pCR) after neoadjuvant chemotherapy is associated with favourable outcomes, a small proportion of patients with pCR have recurrence. This study was designed to identify factors predictive of recurrence in patients with pCR.

Methods:

A total of 449 breast cancer patients received neoadjuvant chemotherapy, and 88 evaluable patients had a pCR, defined as no evidence of invasive carcinoma in the breast at surgery. The clinical stage was II in 61 patients (69%), III in 27 (31%). All patients received taxanes and 92% received anthracyclines. Among 43 patients with HER2-positive tumours, 27 received trastuzumab. Cox regression analyses were performed to identify predictors of recurrence.

Results:

Median follow-up was 46.0 months. There were 12 recurrences, including 8 distant metastases. The rate of locoregional recurrence was 10.4% after breast-conserving surgery, as compared with 2.5% after mastectomy. Multivariate analysis revealed that axillary metastases (hazard ratio (HR), 13.6; P<0.0001) and HER2-positive disease (HR, 5.0; P<0.019) were significant predictors of recurrence. Five of six patients with both factors had recurrence. Inclusion of trastuzumab was not an independent predictor among patients with HER2-positive breast cancer.

Conclusion:

Our study results suggest that HER2 status and axillary metastases are independent predictors of recurrence in patients with pCR.     

Impact of breast cancer subtypes on 3-year survival among adolescent and young adult women

Introduction

Young women have poorer survival after breast cancer than do older women. It is unclear whether this survival difference relates to the unique distribution of hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2)-defined molecular breast cancer subtypes among adolescent and young adult (AYA) women aged 15 to 39 years. The purpose of our study was to examine associations between breast cancer subtypes and short-term survival in AYA women, as well as to determine whether the distinct molecular subtype distribution among AYA women explains the unfavorable overall breast cancer survival statistics reported for AYA women compared with older women.

Methods

Data for 5,331 AYA breast cancers diagnosed between 2005 and 2009 were obtained from the California Cancer Registry. Survival by subtype (triple-negative; HR+/HER2-; HR+/HER2+; HR-/HER2+) and age-group (AYA versus 40- to 64-year-olds) was analyzed with Cox proportional hazards regression with follow-up through 2010.

Results

With up to 6 years of follow-up and a mean survival time of 3.1 years (SD = 1.5 years), AYA women diagnosed with HR-/HER + and triple-negative breast cancer experienced a 1.6-fold and 2.7-fold increased risk of death, respectively, from all causes (HR-/HER + hazard ratio: 1.55; 95% confidence interval (CI): 1.10 to 2.18; triple-negative HR: 2.75; 95% CI, 2.06 to 3.66) and breast cancer (HR-/HER + hazard ratio: 1.63; 95% CI, 1.12 to 2.36; triple-negative hazard ratio: 2.71; 95% CI, 1.98 to 3.71) than AYA women with HR+/HER2- breast cancer. AYA women who resided in lower socioeconomic status neighborhoods, had public health insurance, and were of Black, compared with White, race/ethnicity experienced worse survival. This race/ethnicity association was attenuated somewhat after adjusting for breast cancer subtypes (hazard ratio, 1.33; 95% CI, 0.98 to 1.82). AYA women had similar all-cause and breast cancer-specific short-term survival as older women for all breast cancer subtypes and across all stages of disease.

Conclusions

Among AYA women with breast cancer, short-term survival varied by breast cancer subtypes, with the distribution of breast cancer subtypes explaining some of the poorer survival observed among Black, compared with White, AYA women. Future studies should consider whether distribution of breast cancer subtypes and other factors, including differential receipt of treatment regimens, influences long-term survival in young compared with older women.     

Endothelial follicle-stimulating hormone receptor expression in invasive breast cancer and vascular remodeling at tumor periphery

Background

Follicle-stimulating hormone receptor (FSHR) is expressed on the endothelial surface of blood vessels associated with solid tumor periphery, where angiogenesis is known to occur. The correlation between FSHR expression and formation of new peritumoral vessels has not been previously investigated.

Methods

We used immunohistochemical techniques involving specific antibodies to detect FSHR and the endothelial markers (CD34, VEGFR2, and D2-40) in tissue samples from 83 patients with lymph node-negative, invasive breast cancer representing four main clinical treatment groups: HR+/HER2-, HR+/HER2+, HR-/HER2+ and triple-negative.

Results

The FSHR+ vessels were exclusively located at breast cancer periphery, in a layer that extended 2 mm into and 5 mm outside of the tumor. The percentage of blood vessels expressing FSHR reached a maximum of 100% at the demarcation line between the tumor and the normal tissue. Common among FSHR+ vessels, regardless of breast cancer type, were the high densities of arterioles and venules (6.4 ± 1.4 and 13.9 ± 2.1 vessels/mm², respectively). These values were 3-fold higher that those noticed for CD34+ arterioles and venules associated with normal breast tissue located at a distance greater than 10 mm outside the tumors. The average density of FSHR+ and CD34+ blood vessels as well as of D2-40+ lymphatic vessels did not differ significantly among breast cancer subgroups. FSHR+ vessels did not express VEGFR2. The endothelial FSHR expression correlated significantly with the peritumoral CD34+ vessels’ density (p < 0.001) and tumor size (p = 0.01).

Conclusion

Endothelial FSHR expression in breast cancer is associated with vascular remodeling at tumor periphery.     

Evaluating the predictive value of biomarkers for efficacy outcomes in response to pertuzumab- and trastuzumab-based therapy: an exploratory analysis of the TRYPHAENA study

Introduction

Molecular markers that predict responses to particular therapies are invaluable for optimization of patient treatment. The TRYPHAENA study showed that pertuzumab and trastuzumab with chemotherapy was an efficacious and tolerable combination for patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer in the neoadjuvant setting. We analyzed whether particular biomarkers correlated with the responses observed and therefore may predict outcomes in patients given pertuzumab plus trastuzumab.

Methods

We describe the analysis of a panel of biomarkers including HER2, human epidermal growth factor receptor 3 (HER3), epidermal growth factor receptor (EGFR), phosphatase and tensin homolog (PTEN), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) by qRT-PCR, immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), enzyme-linked immunosorbent assay (ELISA), and PCR-based mutational analyses as appropriate. For each marker analyzed, patients were categorized into ‘low’ (generally below median) or ‘high’ (generally above median) subgroups at baseline and post-treatment.

Results

Correlation of marker subgroups with the achievement of a pathological complete response (pCR) (ypT0/is) was analyzed. HER2 protein and mRNA expression levels were associated with pCR rate in two of the three study arms and the pooled analyses. Correlations of biomarker status with pCR occurred in one individual arm only and the pooled analyses with EGFR and PTEN; however, interpretation of these results is limited by a strong imbalance in patient numbers between the high and low subgroups and inconsistency between arms. We also found no association between expression levels of TOP2A and pCR rate in either the anthracycline-containing or free arms of TRYPHAENA.

Conclusions

According to these analyses, and in line with other analyses of pertuzumab and trastuzumab in the neoadjuvant setting, we conclude that HER2 expression remains the only marker suitable for patient selection for this regimen at present.

Trial registration

The TRYPHAENA study was registered with ClinicalTrials.gov, {"type":"clinical-trial","attrs":{"text":"NCT00976989","term_id":"NCT00976989"}}NCT00976989, on September 14 2009.     

High HER2/Centromeric Probe for Chromosome 17 Fluorescence In Situ Hybridization Ratio Predicts Pathologic Complete Response and Survival Outcome in Patients Receiving Neoadjuvant Systemic Therapy With Trastuzumab for HER2‐Overexpressing Locally Advanced Breast Cancer

Background.

The present study was performed to determine whether the human epidermal growth factor receptor-related 2 (HER2)/centromeric probe for chromosome 17 fluorescence in situ hybridization (FISH) ratio is a predictor of a pathologic complete response (pCR), recurrence-free survival (RFS), and/or overall survival (OS) in patients receiving neoadjuvant systemic treatment (NST) with trastuzumab (NST-T) for HER2+ locally advanced breast cancer (LABC).

Patients and Methods.

The present retrospective study included 555 patients with HER2+ LABC who had undergone NST and definitive surgery (1999–2012); 373 had concurrently received trastuzumab. HER2-positivity was considered present with an immunohistochemical score of 3+ and/or HER2 FISH ratio of ≥2.0. We used logistic regression analysis and Cox proportional hazard modeling to determine whether a high HER2 FISH ratio, either as a continuous variable or with a cutoff of ≥7.0, would predict for pCR (no invasive disease in the breast and no tumor in the ipsilateral axillary lymph nodes), RFS, and/or OS.

Results.

The pCR group’s median HER2 FISH ratio was significantly higher than that of the non-pCR group (6.4 vs. 5.2; p = .003). The logistic regression model demonstrated that the independent predictors of pCR included a high HER2 FISH ratio as a continuous variable (p = .04). The multicovariate Cox proportional hazard model showed that a high HER2 FISH ratio (with a cutoff of ≥7.0 or as a continuous variable) was a significant prognostic indicator of longer RFS time (p = .047 and p = .04, respectively). Similarly, a high HER2 FISH ratio of ≥7.0 was associated with longer OS (p = .06).

Conclusion.

A high HER2 FISH ratio is a predictor of pCR in patients with HER2+ LABC who receive NST-T.

Implications for Practice:

This study demonstrated the optimal predictive and prognostic value of a HER2/centromeric probe for chromosome 17 FISH ratio for primary HER2+ breast cancer treated with trastuzumab combined with neoadjuvant systemic treatment (NST-T). This suggests that a high HER2 FISH ratio is a potential indicator for a high pathologic complete response rate and a better prognosis when patients are treated with NST-T.     

Effect of adjuvant trastuzumab among patients treated with anti-HER2-based neoadjuvant therapy

Purpose:

To study the impact of adjuvant trastuzumab among patients achieving a pathologic complete response (pCR) after trastuzumab-based neoadjuvant systemic therapy (NST).

Patients and methods:

Patients with primary HER2-positive breast cancer treated with trastuzumab-based NST were categorised according to adjuvant trastuzumab administration and pCR status. Adjuvant trastuzumab became standard of care in 2006, this was the main reason patients in our cohort did not receive adjuvant trastuzumab. Kaplan–Meier was used to estimate survival. A test for interaction between adjuvant trastuzumab and pCR was completed.

Findings:

Of 589 patients, 203 (34.5%) achieved a pCR. After surgery, 109 (18.5%) patients in the entire cohort did not receive adjuvant trastuzumab. Among patients achieving a pCR, 31.3% received adjuvant trastuzumab compared with 68.8% among those who did not achieve a pCR (P=0.0006). Among patients achieving pCR, adjuvant trastuzumab did not further improve overall survival (OS) or relapse-free survival (RFS) (P=0.35 and P=0.93, respectively). Any benefit of adjuvant trastuzumab in OS and RFS among patients without a pCR did not achieve statistical significance (P=0.3 and P=0.44, respectively).

Conclusions:

In this cohort, patients treated with trastuzumab-based NST who achieved a pCR have excellent outcome regardless of whether they received adjuvant trastuzumab.     

A BRCA1 deficient-like signature is enriched in breast cancer brain metastases and predicts DNA damage-induced poly (ADP-ribose) polymerase inhibitor sensitivity

Introduction

There is an unmet clinical need for biomarkers to identify breast cancer patients at an increased risk of developing brain metastases. The objective is to identify gene signatures and biological pathways associated with human epidermal growth factor receptor 2-positive (HER2+) brain metastasis.

Methods

We combined laser capture microdissection and gene expression microarrays to analyze malignant epithelium from HER2+ breast cancer brain metastases with that from HER2+ nonmetastatic primary tumors. Differential gene expression was performed including gene set enrichment analysis (GSEA) using publicly available breast cancer gene expression data sets.

Results

In a cohort of HER2+ breast cancer brain metastases, we identified a gene expression signature that anti-correlates with overexpression of BRCA1. Sequence analysis of the HER2+ brain metastases revealed no pathogenic mutations of BRCA1, and therefore the aforementioned signature was designated BRCA1 Deficient-Like (BD-L). Evaluation of an independent cohort of breast cancer metastases demonstrated that BD-L values are significantly higher in brain metastases as compared to other metastatic sites. Although the BD-L signature is present in all subtypes of breast cancer, it is significantly higher in BRCA1 mutant primary tumors as compared with sporadic breast tumors. Additionally, BD-L signature values are significantly higher in HER2-/ER- primary tumors as compared with HER2+/ER + and HER2-/ER + tumors. The BD-L signature correlates with breast cancer cell line pharmacologic response to a combination of poly (ADP-ribose) polymerase (PARP) inhibitor and temozolomide, and the signature outperformed four published gene signatures of BRCA1/2 deficiency.

Conclusions

A BD-L signature is enriched in HER2+ breast cancer brain metastases without pathogenic BRCA1 mutations. Unexpectedly, elevated BD-L values are found in a subset of primary tumors across all breast cancer subtypes. Evaluation of pharmacological sensitivity in breast cancer cell lines representing all breast cancer subtypes suggests the BD-L signature may serve as a biomarker to identify sporadic breast cancer patients who might benefit from a therapeutic combination of PARP inhibitor and temozolomide and may be indicative of a dysfunctional BRCA1-associated pathway.     

Pathological complete response and prognosis after neoadjuvant chemotherapy for HER2-positive breast cancers before and after trastuzumab era: results from a real-life cohort

Background:

Trastuzumab was introduced a decade ago and has improved outcomes for HER2-positive breast cancer. We investigated the factors predictive of pathological complete response (pCR), prognostic factors for disease-free survival (DFS), and interactions between pCR and DFS after neoadjuvant treatment.

Methods:

We identified 287 patients with primary HER2-positive breast cancers given neoadjuvant chemotherapy (NAC) between 2002 and 2011. Univariate and multivariate analyses of clinical and pathological factors associated with pCR and DFS were performed.

Results:

pCR rates differed between patients receiving neoadjuvant trastuzumab treatment or not (47.7% versus 19.3%, P<0.0001). DFS also differed significantly between patients receiving adjuvant trastuzumab or not (hazard ratio=4.84, 95% CI (2.52; 9.31), P<0.001). We analysed 199 patients given neoadjuvant and adjuvant trastuzumab. Multivariate analysis identified older age and hormone receptor-negative tumours as independent predictors of pCR. T stage (hazard ratio=2.55, 95% CI (1.01; 6.48), P=0.05) and strict pCR (hazard ratio=9.15, 95% CI (1.22; 68.83), P=0.03) were independent predictors of DFS. The latter association was significant in the HR-negative subgroup (P=0.02) but not in the HR-positive subgroup (P=0.12).

Conclusions:

Major pCR and DFS gains in HER2-positive BC were observed since ‘trastuzumab'' era. Further improvements rely on the enrollment of accurately selected patients into clinical trials.     

Comparison of Doxorubicin Plus Docetaxel Neoadjuvant Chemotherapy with Doxorubicin Plus Vinorelbine in Primary Breast Cancer

Purpose

This study was performed to compare the therapeutic efficacy and toxicity of doxorubicin plus docetaxel neoadjuvant chemotherapy (NC) with doxorubicin plus vinorelbine NC.

Methods

Fifty-three patients underwent 4 cycles of NC consisted of intravenous injection of doxorubicin (50 mg/m²) plus docetaxel (75 mg/m²) administered every 3 weeks (AD), while 49 patients underwent 4 cycles of NC consisted of intravenous injection of doxorubicin (50 mg/m²) and vinorelbine (25 mg/m²) administered every 3 weeks (AN). Response rate and treatment-related toxicities were analyzed by administered chemotherapeutics. Response to NC was also analyzed according to clinicobiological characteristics of the primary tumors.

Results

Clinical response was observed in 66% with AN and 81.6% with AD chemotherapy. A complete pathologic response (pCR) was confirmed in 6 patients (11.3%) with AN and in 7 patients (14.3%) with AD after the surgery. Response rate was significantly higher in AD compared with AN (p=0.038), but there was no significant difference between the two group regard to pCR rate. Breast conserving surgery (BCS) was performed in 35.8% of AN group, whereas 20 patients (40.8%) of AD group underwent BCS. The patients with HER2-amplified tumor showed significantly increased response to both types of NC. Pathologic complete response was confirmed in 9 (39.1%) out of 23 HER2-amplified tumors, whereas only 4 (5.1%) of 79 HER2-nonamplified tumors showed pathologic complete response. Febrile neutropenia occurred in 22.6% of total 212 cycles in AN and 38.8% of total 196 cycles in AD. Grade 3/4 neutropenia was observed in 39.6% in AN and 43.9% in AD. Grade 3 mucositis was observed in 26.4% with AN and in 40.8% with AD.

Conclusion

There was no significant increase of pCR by AD compared with AN. Long-term follow-up results of our study indicate that clinical outcome after NC was significantly associated with initial response to NC regardless of therapeutic regimens.     

High-resolution genomic and expression analyses of copy number alterations in HER2-amplified breast cancer

Introduction

HER2 gene amplification and protein overexpression (HER2+) define a clinically challenging subgroup of breast cancer with variable prognosis and response to therapy. Although gene expression profiling has identified an ERBB2 molecular subtype of breast cancer, it is clear that HER2+ tumors reside in all molecular subtypes and represent a genomically and biologically heterogeneous group, needed to be further characterized in large sample sets.

Methods

Genome-wide DNA copy number profiling, using bacterial artificial chromosome (BAC) array comparative genomic hybridization (aCGH), and global gene expression profiling were performed on 200 and 87 HER2+ tumors, respectively. Genomic Identification of Significant Targets in Cancer (GISTIC) was used to identify significant copy number alterations (CNAs) in HER2+ tumors, which were related to a set of 554 non-HER2 amplified (HER2-) breast tumors. High-resolution oligonucleotide aCGH was used to delineate the 17q12-q21 region in high detail.

Results

The HER2-amplicon was narrowed to an 85.92 kbp region including the TCAP, PNMT, PERLD1, HER2, C17orf37 and GRB7 genes, and higher HER2 copy numbers indicated worse prognosis. In 31% of HER2+ tumors the amplicon extended to TOP2A, defining a subgroup of HER2+ breast cancer associated with estrogen receptor-positive status and with a trend of better survival than HER2+ breast cancers with deleted (18%) or neutral TOP2A (51%). HER2+ tumors were clearly distinguished from HER2- tumors by the presence of recurrent high-level amplifications and firestorm patterns on chromosome 17q. While there was no significant difference between HER2+ and HER2- tumors regarding the incidence of other recurrent high-level amplifications, differences in the co-amplification pattern were observed, as shown by the almost mutually exclusive occurrence of 8p12, 11q13 and 20q13 amplification in HER2+ tumors. GISTIC analysis identified 117 significant CNAs across all autosomes. Supervised analyses revealed: (1) significant CNAs separating HER2+ tumors stratified by clinical variables, and (2) CNAs separating HER2+ from HER2- tumors.

Conclusions

We have performed a comprehensive survey of CNAs in HER2+ breast tumors, pinpointing significant genomic alterations including both known and potentially novel therapeutic targets. Our analysis sheds further light on the genomically complex and heterogeneous nature of HER2+ tumors in relation to other subgroups of breast cancer.