EPIDEMIOLOGICAL STUDY AND MOLECULAR BREAST CANCER SUBTYPES DISTRIBUTION AMONG WEST ALGERIAN PATIENTS
AMINA BELHADJ *
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
LYNDA ADDOU- KLOUCHE
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
MERIEM KAOUTER BENYELLES
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
AMINA BENDAOUD
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
IKRAM ZIANE
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
BADRA ZAKMOUT
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
ISSAM BOUAKLINE
Anatomy and Pathology Laboratory, Regional Military Hospital University, Oran, 31000, Algeria
MILOUD MEDJAMIA
Anatomy and Pathology Laboratory, Regional Military Hospital University, Oran, 31000, Algeria
HAMID JELLOUL BENAMMAR
Anatomy and Pathology Laboratory, University Hospital, Sidi Bel Abbes 22000, Algeria
SOFIANE BOUAZZA
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
ZOHEIR DAHMANI
Laboratory of Applied Molecular Biology and Immunology, University Abou Bakr Seddik, Tlemcen 13000, Algeria
MOHAMED BENALI
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
SORAYA MOULESSEHOUL
Department of Biology, Biotoxicology Laboratory, University Djillali Liabes, BP 89 Avenue Larbi Ben Mehidi, Sidi Bel Abbes 22000, Algeria
*Author to whom correspondence should be addressed.
Abstract
Purpose: Breast cancer is the leading cause of cancer death in women worldwide and in particular in Algeria. Breast cancer is a heterogenous disease; its molecular classification is based on gene expression and on proteomic profile to distinguish five major subtypes: luminal A, Luminal B, HER2+, basal like and normal like. We aimed in present study to achieve an epidemiologic study and to correlate molecular breast cancer subtypes with clinico pathological features among west Algerian patients.
Materials and Methods: We performed a retrospective study on 829 patients diagnosed with primary breast cancer who underwent initial surgery in west Algeria Hospitals between january 2008 and December 2013. Assessment of estrogen/progesterone receptors and HER2 protein expression on some cases was determined by immunohistochemistry. Molecular subtypes definitions were as follows: Luminal A (ER+, PR+/-, HER2-), luminal B ( ER+, PR+/-, HER2+), Triple negative (ER-, PR-, HER2-), HER2+( ER-, PR-, HER+), they were correlated with some clinical characteristics: median age, histological type, SBR grade and pathological axillary lymph node status.
Results: The mean and median age of the 829 patients were 50.66 and 49 years respectively. 62% of the patients had positive lymph nodes and 11% had distant metastasis at diagnosis. Metastasis free survival at 5 years was 70%. Proportions of molecular subtypes were as follows: 41.86% luminal A, 29.58% triple negative breast cancer, 15.09% luminal B and 13.46% HER2+. A significant difference was noted with axillary lymph node (P=0.038), Invasive ductal carcinoma was predominant among all molecular subtypes, Luminal A patients represents the highest proportion of axillary lumph node, and all women represent to diagnosis at the intermediate or late stages of breast cancer.
Conclusions: The distribution of molecular subtypes of breast cancer differs when comparing to other countries, Luminal A subtype is the commonest subtype among West Algerian patients. Women were young and had an aggressive breast cancer profile this might be due to high prevalence of triple negative breast cancer subtype. This study will lead to enhance the care of patients.
Keywords: Breast cancer, West Algeria, molecular subtype, proportion