Mast Cells as an Indicator and Prognostic Marker in Molecular Subtypes of Breast Cancer.

BACKGROUND/AIM: Mast cells (MCs) represent the most controversial non-malignant element of the tumor microenvironment. Our aim was to study how MCs density and distribution (intratumoral-MCit versus peritumoral-MCpt) relate to tumor grade and molecular subtypes. MATERIALS AND METHODS: MCs tryptase immunohistochemistry was performed on 80 cases of breast carcinomas. RESULTS: For Luminal A tumors, a partial correlation was detected between MCit and progesterone receptor (PR) (p=0.005). Luminal B tumors showed a significant correlation between MCpt and age (p=0.009), estrogen receptor (ER) (p=0.017) and PR (p=0.035). MCit and MCpt were strongly interrelated in this subtype (p=0.002) and in triple-negative breast cancers (p=0.002). In HER2 subtype, MCpt tumors were significantly correlated with HER2 (p=0.044). In G2 tumors, MCpt correlated with ER (p=0.015) and PR (p=0.038) while in G3 tumors ER correlated with both MCit (p=0.009) and MCpt (p=0.000487) tumors. CONCLUSION: MCs dynamics are strongly influenced by hormone receptors and HER2 status. MCit increased in aggressive tumor types and is a worse prognostic factor.

Invasive ductal carcinoma of no special type and its corresponding lymph node metastasis: do they have the same immunophenotypic profile?

In the present study we compared the immunophenotypic subtypes of breast ductal invasive carcinomas with their ipsilateral, axillary lymph node metastasis. The ER (estrogen receptor), PR (progesterone receptor), Her2 (human epidermal growth factor receptor 2), and CK5 (cytokeratin 5) status and the proliferation marker Ki-67 were determined by immunohistochemistry on specimens from 43 women. All selected cases were diagnosed as invasive breast carcinomas, of no special type (NST), G2 grade of differentiation. The most frequently encountered subtype at both sites was luminal B. We determined that tumor profile evaluated by surrogate markers is not stable during the metastatic process. The total rate of shifted cases was 23.26% (10 cases), and the highest rate of shifting (6.98%) was encountered from luminal B/Ki-67 to luminal A subtype. In five cases, the subtype shifted to a poorer one according to prognosis. These data support the hypothesis that breast cancer is a heterogeneous disease, with substantial variability of cellular components within each category, a statement applicable to invasive breast carcinomas of NST type too. The receptor profile of this carcinoma, indicated by surrogate markers, is not stable throughout the metastatic process.

Differential expression of e-cadherin in primary breast cancer and corresponding lymph node metastases.

BACKGROUND/AIM: E-Cadherin is a marker with a controversial function. Its role is often interpreted in the context of the epithelial-mesenchymal transition. In ambiguous cases, it is used as a phenotypic marker of lobular subtype of breast carcinoma. It has been well-studied in primary cancer, but its expression after metastasis is not well-described. The aim of this study was to determine the evolution of E-cadherin expression in no special type (NST) primary breast carcinoma and to correlate this with that in distant, paired nodal metastases (LNM) and molecular classification. MATERIAL AND METHODS: We processed 88 invasive breast carcinomas of NST type and their paired LNM. The specimens were formalin-fixed and paraffin embedded. Sections were immunostained for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (Her2), basal cytokeratin CK5, nuclear protein Ki67 and E-cadherin with a Leica Bond-Max autostainer. RESULTS: The results obtained were grouped into four molecular subtypes: Luminal A, luminal B, HER2-overexpressing, and triple-negative/basal-like. We found that the frequency of E-cadherin expression was higher (95.45%) in primary sites than in LNM (72.73%). E-Cadherin from primary breast cancer correlated positively only with E-cadherin in LNM (p≤0.003). A single positive correlation of E-cadherin with ER (p≤0.007) LNM was found. CONCLUSION: E-Cadherin expression is not stable during the metastatic process. Its expression in LNM is lower than in primary sites. E-Cadherin expression in primary sites positively correlates with E-cadherin from LNM.

Hormone receptors and HER2 expression in primary breast carcinoma and corresponding lymph node metastasis: do we need both?

BACKGROUND: Scattered studies report on controversial results concerning evaluation of primary breast tumors and their matched lymph node metastases. Aim. To investigate the molecular profile of primary breast tumors and corresponding lymph node metastases (LNM) based on estrogen receptor (ER), progesterone receptor (PR) and human epiderma growth factor receptor-2 (HER2 protein). MATERIALS AND METHODS: Sixty-six primary tumors and corresponding axillary lymph node metastases were evaluated by immunohistochemistry for ER, PR and HER2 protein. According to these markers, cases were stratified as Luminal A, B, HER2 subtypes and triple-negative. Results. Thirteen out of 66 cases (19.7%) exhibited different tumor cell phenotypes in nodal metastases compared to primary breast tumors. All cases with hybrid phenotype had metastases with a pure HER2 phenotype. The most frequent switching was observed from luminal A to luminal B phenotype. CONCLUSION: The high rate of discrepancy between primary tumor and nodal metastasis phenotype imposes the need for a comparative assessment of both primary tumor and nodal metastasis before any therapeutic decision, in order to avoid recurrence and to improve patient prognosis and overall survival.