Axillary lymph node status of operable breast cancers by combined steroid receptor and HER-2 status: triple positive tumours are more likely lymph node positive

Estrogen receptor positive operable breast cancer: does menopausal status impact on HER2 and progesterone receptor status?

PURPOSE

The objective of the present study was to determine whether progesterone receptor (PgR) and human epidermal growth factor receptor 2 (HER2) status differs by menopausal status in estrogen receptor (ER)-positive breast cancers.

PATIENTS AND METHODS

We retrospectively analyzed the clinicopathological data of 588 with operable ER(+) breast cancers patients. ER, HER2 and PgR expression in the tumor specimens were examined by immunohistochemistry. The relationship between different variables was assessed by Pearson's χ(2) and Fisher's exact probability tests in univariate analyses. Logistic regression was used for multivariate analyses of relationship between HER2 expression and selected clinicopathological characteristics. Maximum likelihood estimates of the odds ratio (OR) were obtained and 95% confidence intervals (CI) were calculated.

RESULTS

In the postmenopausal women with ER(+) tumors, HER2 was independently inversely associated with PgR expression (P = 0.017; OR 3.02; 95% CI 1.22-7.49). An ER(+)/PgR(-) tumor was 3.02 times more likely to express HER2 than an ER(+)/PgR(+) tumor in the postmenopausal women. However, an ER(+) tumor in the premenopausal patients failed to show an independent relationship between HER2 and PgR.

CONCLUSION

Menopausal status played a very important role in determining HER2 and PgR status in ER(+) breast cancer patients. HER2 was independently inversely associated with PgR only in the postmenopausal women with ER(+) breast cancers but not in the premenopausal ones.

The molecular subtype classification is a determinant of sentinel node positivity in early breast carcinoma

Introduction

Several authors have underscored a strong relation between the molecular subtypes and the axillary status of breast cancer patients. The aim of our work was to decipher the interaction between this classification and the probability of a positive sentinel node biopsy.

Materials and Methods

Our dataset consisted of a total number of 2654 early-stage breast cancer patients. Patients treated at first by conservative breast surgery plus sentinel node biopsies were selected. A multivariate logistic regression model was trained and validated. Interaction covariate between ER and HER2 markers was a forced input of this model. The performance of the multivariate model in the training and the two validation sets was analyzed in terms of discrimination and calibration. Probability of axillary metastasis was detailed for each molecular subtype.

Results

The interaction covariate between ER and HER2 status was a stronger predictor (p = 0.0031) of positive sentinel node biopsy than the ER status by itself (p = 0.016). A multivariate model to determine the probability of sentinel node positivity was defined with the following variables; tumour size, lympho-vascular invasion, molecular subtypes and age at diagnosis. This model showed similar results in terms of discrimination (AUC = 0.72/0.73/0.72) and calibration (HL p = 0.28/0.05/0.11) in the training and validation sets. The interaction between molecular subtypes, tumour size and sentinel nodes status was approximated.

Discussion

We showed that biologically-driven analyses are able to build new models with higher performance in terms of breast cancer axillary status prediction. The molecular subtype classification strongly interacts with the axillary and distant metastasis process.

Axillary lymph node dissection in early-stage invasive breast cancer: is it still standard today?

Evaluation of axillary lymph node status by sentinel lymph node biopsy (SLNB) and complete axillary lymph node dissection (ALND) are an inherent part of breast cancer treatment. Increased understanding of tumor biology has changed the prognostic and therapeutic impact of lymph node status. Non-invasive imaging techniques like axillary ultrasound, FDG-PET, or MRI revealed moderate sensitivity and high specificity in evaluation of lymph node status. Therefore, they are not sufficient for lymph node staging. Otherwise, the impact of remaining micrometastases and even macrometastases for prognosis and treatment decisions is overestimated. Considering tumor biology, the distinction of axillary metastases in isolated tumor cells (ITC, pN0(i+)); micrometastases (pN1mi), and macrometastases (pN1a) is not comprehensible. Increasing data support the thesis that remaining axillary metastases neither increase the axillary recurrence rate nor decrease overall survival. It is doubtful that axillary tumor cells are capable to complete the complex multistep metastatic process. If applied, axillary metastases are sensitive to systemic treatment and are targeted by postoperative tangential breast irradiation. Therefore, the controversy about the clinical relevance of tumor cell clusters or micrometastases in SLN is a sophisticated but not contemporary discussion. Currently, there is no indication for axillary surgery in elderly patients with favorable tumors and clinically tumor-free lymph nodes. Nonetheless, a rational and evidence-based approach to the management of clinically and sonographically N0 patients with planned breast-conserving surgery and limited tumor size is needed now.

A risk stratification by hormonal receptors (ER, PgR) and HER-2 status in small (< or = 1 cm) invasive breast cancer: who might be possible candidates for adjuvant treatment?

As the use of screening mammography expands, the proportion of invasive breast cancer > or = 1 cm is increasing. The aims of this study were: (1) to identify risk factors for systemic metastases in patients with > or = 1 cm invasive breast cancer and (2) to investigate the patient groups at the greatest risk for metastases with such small tumors. Data were collected retrospectively from the breast cancer registry of our institution for patients with invasive breast cancer from October 1994 to December 2004. Of 4,036 patients who received curative breast cancer surgery, we identified 427 patients who had T1a or T1b breast cancer excluding 39 patients who received neoadjuvant chemotherapy. Ipsilateral axillary lymph node involvement was found in 13% (57/427) of patients at the time of surgery. A multivariate analysis was conducted in 370 (T1aN0, T1bN0) patients without lymph node involvement. In a Cox-regression model, HER-2 positive and triple negative (TN) groups were identified as independent risk factors to predict distant relapse-free survival (DRFS) [Hazard ratio (HR) 8.8, P = 0.003 for HER-2 positive group; HR 5.1, P = 0.026 for TN group] in T1bN0 tumors. Statistical significance was not maintained when the analysis was limited to T1aN0 tumors. Even though T1aN0 and T1bN0 tumors have a relatively low risk of systemic failure, antiHER-2-directed therapy for HER-2 group and new innovative adjuvant systemic treatment for TNBC patients with T1bN0 tumors should be considered. Prospective adjuvant trials are warranted in these subgroups of patients.

Variation in breast cancer subtypes with age and race/ethnicity

BACKGROUND

Both age and race have been identified as independent predictors of breast cancer subtype but the association of age with subtype within each race is not well understood. This study assesses the association of age with the eight breast cancer subtypes as defined by ER/PR/HER2 among white, African-American, Hispanic, and Asian/Pacific Islander women.

METHODS

This study included 69,358 women with primary invasive breast cancer. Logistic regression was used to assess the association of age with each of the ER/PR/HER2 subtypes for each race adjusted for socioeconomic status, stage, grade, and tumor size.

RESULTS

The odds of African-American women having a triple-negative tumor were not statistically significantly increased for women under 46 when compared to the African-American women aged 46-69 (OR=0.96; 95% CI=0.80-1.16). A similar pattern was observed for the ER-/PR-/HER2+ subtype. Hispanic women under age 46 (OR=0.83; 95% CI=0.71-0.97) and over age 70 (OR=0.71; 95% CI=0.57-0.89) were less likely to have the ER-/PR-/HER2+ subtype. Asian/Pacific Islander women under age 46 also had reduced odds (OR=0.67; 95% CI=0.55-0.82) of the ER-/PR-/HER2+ subtype.

CONCLUSIONS

The ER/PR/HER2 subtypes vary with age and differences in this variation depend on race. It is important to define breast cancer using the ER/PR/HER2 subtype and the significance of age and race should not be overlooked.

Triple-negative breast cancer and obesity in a rural Appalachian population

BACKGROUND

Our objective was to determine the clinicopathologic features of triple-negative (estrogen receptor, progesterone receptor, and human epidermal growth factor-2 receptor negative) breast cancer and their relationship to obesity in women drawn from a population with one of the highest obesity rates in the United States.

METHODS

This retrospective study involved 620 White patients with invasive breast cancer in West Virginia. Hospital tumor registry, charts, and pathology records provided age at diagnosis, tumor histologic type, size, nodal status, and receptor status. Body mass index was calculated and a value of > or = 30 was considered indicative of obesity.

RESULTS

Triple-negative tumors occurred in 117 (18.9%) of the 620 patients, most often in association with invasive ductal carcinomas. Patients with triple-negative tumors were younger than those with other receptor types, 44.5% and 26.7%, respectively, being diagnosed at age <50 years (P = 0.0004). The triple-negative tumors were larger (P = 0.0003), most notably in the younger women, but small tumors (<2.0 cm) were more often accompanied by lymph node metastases. Obesity was present in 49.6% of those with triple-negative tumors but in only 35.8% of those with non-triple-negative tumors (P = 0.0098). Lymph node metastases were more frequently associated with T(2) tumors in obese patients (P = 0.032) regardless of their receptor status.

CONCLUSIONS

Triple-negative breast cancers within a White, socioeconomically deprived, population occurred in younger women, with later stage at diagnosis, and in association with obesity, which itself has been associated with a poor prognosis in breast cancer.

Short-term outcome of primary operated early breast cancer by hormone and HER-2 receptors

INTRODUCTION

Prognostic subgroup classification of operable breast cancers using cDNA clustering of breast cancer-related genes resembles the classification based on the combined immunohistochemical (IHC) expression of the hormone and HER-2 receptors. We here report the short-term disease-free interval (DFI) of operable breast cancers by their joint hormone receptor/HER-2 phenotype.

PATIENTS AND METHODS

Short-term follow-up (FU) of a prospective cohort of 1,958 breast-cancer patients primary operated at our institution between 2000 and 2005. Receptors were evaluated using IHC. Steroid receptors were considered positive for any nuclear staining; HER-2 for strong (3+) membrane staining or positive fluorescence in situ hybridization (FISH). Kaplan-Meier (KM) DFI curves were calculated for any relapse defined as a local, regional, contralateral, or distant breast cancer event for the six predefined breast cancer subgroups: ER + PR + HER-2 - (PPN), ER + PR - HER-2 - (PNN), ER + PR + HER-2 + (PPP), ER - PR - HER-2 - (NNN), ER - PR - HER-2 + (NNP), and ER + PR - HER-2 + (PNP). P-values were calculated for comparison of the six different survival curves using two possible adaptations for multiple testing. A multivariate model for the receptors predicting DFI did incorporate local and systemic adjuvant therapy.

RESULTS

Median patient age was 57 years (ranges 26-96) and median FU was 3.35 years. Overall, DFI at median FU was 91%; 94% for PPN, 89% for PNN, 86% for NNN, 81% for PPP, 80% for PNP, and 76% for NNP cases. Some receptor subgroups had a significantly better DFI than others based on multiple testing, especially when the PPN group was compared against the four most frequent subtypes. The multivariate model with local and systemic adjuvant therapy confirmed the prognostic value of ER, PR, and HER-2 for short-term DFI.

CONCLUSION

It is possible to distinguish short-term prognostic breast cancer subgroups only on the basis of ER, PR, and HER-2 even when stratified for local and systemic adjuvant therapy. While gene expression profiles based on microarray data of over hundreds of genes will probably teach us much about breast cancer biology, heterogeneity, and prognosis, we emphasize the important short-term prognostic value of currently used IHC markers for ER, PR, and HER-2.