Luminal B tumors are the most frequent molecular subtype in breast cancer of North African women: an immunohistochemical profile study from Morocco

Abstract

BackgroundBreast cancer may be classified into luminal A, luminal B, HER2+/ER-, basal-like and normal-like subtypes based on gene expression profiling or immunohistochemical (IHC) characteristics. The aim of our study is to show the molecular profile characteristic of breast cancer in the North African population of Morocco. This work showed preliminary results and correlations with clinicopathological and histological parameters. Three hundred and ninety primary breast carcinomas tumor tissues were immunostained for ER, PR, HER2, CK5/6, CK8/18 and Ki67 using paraffin tissue.MethodsWe reviewed 390 cases of breast cancer diagnosed on January 2008 to December 2011 at the Department of pathology, Hassan II teaching hospital, Fez, Morocco. Age, size tumor, metastatic profile, node involvement profile, histological type and immunohistochemical profile were studied.ResultsThe average age was 46 years; our patients were diagnosed late with a high average tumor size. Luminal B subtype was more prevalent (41.8%), followed by luminal A (30.5%), basal-like (13, 6%), Her2-overexpressing (9, 2%), and unclassified subtype (4.9%).ConclusionThis study showed that molecular classification and biological profile may be different according to geographical distribution, to encourage further studies to know the genomic profile of tumors and the environment.Virtual slidehttp://www.diagnosticpathology.diagnomx.eu/vs/1675272504826544

Correlation between p53 and epidermal growth factor receptor expression in breast cancer classification

“…In this study, the Expert Consensus of the 2013 St. Gallen International Breast Cancer Conference was used to analyze the subtypes of breast cancer and showed that luminal B was the most common subtype (37.5%) in this group of subjects, followed by TNBC (26.1%), luminal A (23.9%), and the HER2-enriched subtype (12.5%), findings consistent with the results from El Fatemi et al (2012), Howland et al (2013), andGoldhirsch et al (2013). In this study, the positive rate of CK5/6 was 52.2% in TNBC.…”

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“…For p53, EGFR, and CK5/6, at least 10% of cells positively stained were considered as positive. According to the Expert Consensus of the 2013 St. Gallen International Breast Cancer Conference (Goldhirsch et al, 2013), breast cancer can be divided into four subtypes on the basis of their molecular markers (Table 1). …”

Clinicopathological Features of Indonesian Breast Cancers with Different Molecular Subtypes

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Characteristics of incident female breast cancer in Lebanon, 1990–2013: Descriptive study of 612 cases from a hospital tumor registry

“…In Tunisia, 51% of their patients belong to the luminal A and 23% to the triple negative group, HER2 is overexpressed in 13% of their tumors [25]. Morocco presents luminal B as the most prevalent group (42%) followed by luminal A at 31%, HER2 was positive in 5% [26].…”