Glioblastoma Vaccines as Promising Immune-Therapeutics: Challenges and Current Status.

Glioblastoma (GBM) is the most common and aggressive malignant brain tumor. Standard treatments including surgical resection, radiotherapy, and chemotherapy, have failed to significantly improve the prognosis of glioblastoma patients. Currently, immunotherapeutic approaches based on vaccines, chimeric antigen-receptor T-cells, checkpoint inhibitors, and oncolytic virotherapy are showing promising results in clinical trials. The combination of different immunotherapeutic approaches is proving satisfactory and promising. In view of the challenges of immunotherapy and the resistance of glioblastomas, the treatment of these tumors requires further efforts. In this review, we explore the obstacles that potentially influence the efficacy of the response to immunotherapy and that should be taken into account in clinical trials. This article provides a comprehensive review of vaccine therapy for glioblastoma. In addition, we identify the main biomarkers, including isocitrate dehydrogenase, epidermal growth factor receptor, and telomerase reverse transcriptase, known as potential immunotherapeutic targets in glioblastoma, as well as the current status of clinical trials. This paper also lists proposed solutions to overcome the obstacles facing immunotherapy in glioblastomas.

Prognostic Value of ATRX and p53 Status in High-Grade Glioma Patients in Morocco.

INTRODUCTION: Glioblastoma and astrocytoma, grade 4, are the most common and aggressive brain tumors. Several biomarkers, such as the isocitrate dehydrogenase mutation (IDH-1), alpha-thalassemia/mental retardation, and the X-linked mutation (ATRX), enable more accurate glioma classification and facilitate patient management. This study aimed to determine the prognostic value of clinical and molecular factors (IDH, TP53, and ATRX mutations). We also studied the relationship between these molecular markers and the overall survival (OS) of 126 patients with grade 4 glioblastoma/astrocytoma. METHODS: The immunohistochemical study was conducted using antibodies namely, IDH1, R132H, p53, and ATRX. Statistical tests were used to investigate factors that might influence overall survival using IBM SPSS Statistics, version 25.0 (IBM Corp., Armonk, NY). RESULTS: The median age at diagnosis was 51.5 years. Patients with a Karnofsky performance score (KPS) <70 presented less favorable survival outcomes compared to those with a KPS ≥70. The median OS for patients was found to be 11.17 months. Expression of IDH1 R132H was found in 13.5% of patients, p53 overexpression was identified in 55.6% of cases, and loss of ATRX expression was detected in 11.9%. The group of patients with IDH mutant/ATRX mutant/p53 wild-type had the best prognosis (OS = 27.393 months; p = 0.015). Our results were in line with previous studies. CONCLUSION: The clinical value of IDH and ATRX mutations in prognostic assessment was confirmed (p ≤0.05). The overexpression of p53 had no significant impact on OS (p = 0.726). Therefore, p53 alone cannot predict survival in glioblastoma patients. Based on the results, these biomarkers may be a potential therapeutic target to prolong patient survival, hence the need for further investigations.

New Biomarkers and Treatment Advances in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is a specific subtype of breast cancer lacking hormone receptor expression and HER2 gene amplification. TNBC represents a heterogeneous subtype of breast cancer, characterized by poor prognosis, high invasiveness, high metastatic potential, and a tendency to relapse. In this review, the specific molecular subtypes and pathological aspects of triple-negative breast cancer are illustrated, with particular attention to the biomarker characteristics of TNBC, namely: regulators of cell proliferation and migration and angiogenesis, apoptosis-regulating proteins, regulators of DNA damage response, immune checkpoints, and epigenetic modifications. This paper also focuses on omics approaches to exploring TNBC, such as genomics to identify cancer-specific mutations, epigenomics to identify altered epigenetic landscapes in cancer cells, and transcriptomics to explore differential mRNA and protein expression. Moreover, updated neoadjuvant treatments for TNBC are also mentioned, underlining the role of immunotherapy and novel and targeted agents in the treatment of TNBC.

Clinical Evidence of Circulating Tumor DNA Application in Aggressive Breast Cancer.

Breast cancer is clinically and biologically heterogeneous and is classified into different subtypes according to the molecular landscape of the tumor. Triple-negative breast cancer is a subtype associated with higher tumor aggressiveness, poor prognosis, and poor response to treatment. In metastatic breast cancer, approximately 6% to 10% of new breast cancer cases are initially staged IV (de novo metastatic disease). The number of metastatic recurrences is estimated to be 20-30% of all existing breast tumor cases, whereby the need to develop specific genetic markers to improve the prognosis of patients suffering from these deadly forms of breast cancer. As an alternative, liquid biopsy methods can minutely identify the molecular architecture of breast cancer, including aggressive forms, which provides new perspectives for more precise diagnosis and more effective therapeutics. This review aimed to summarize the current clinical evidence for the application of circulating tumor DNA in managing breast cancer by detailing the increased usefulness of this biomarker as a diagnostic, prognostic, monitoring, and surveillance marker for breast cancer.

Molecular and Circulating Biomarkers in Patients with Glioblastoma.

Glioblastoma is the most aggressive malignant tumor of the central nervous system with a low survival rate. The difficulty of obtaining this tumor material represents a major limitation, making the real-time monitoring of tumor progression difficult, especially in the events of recurrence or resistance to treatment. The identification of characteristic biomarkers is indispensable for an accurate diagnosis, the rigorous follow-up of patients, and the development of new personalized treatments. Liquid biopsy, as a minimally invasive procedure, holds promise in this regard. The purpose of this paper is to summarize the current literature regarding the identification of molecular and circulating glioblastoma biomarkers and the importance of their integration as a valuable tool to improve patient care.

Reproduction of the Cancer Genome Atlas (TCGA) and Asian Cancer Research Group (ACRG) Gastric Cancer Molecular Classifications and Their Association with Clinicopathological Characteristics and Overall Survival in Moroccan Patients.

INTRODUCTION: The Cancer Genome Atlas (TCGA) project and Asian Cancer Research Group (ACRG) recently categorized gastric cancer into molecular subtypes. Nevertheless, these classification systems require high cost and sophisticated molecular technologies, preventing their widespread use in the clinic. This study is aimed to generating molecular subtypes of gastric cancer using techniques available in routine diagnostic practice in a series of Moroccan gastric cancer patients. In addition, we assessed the associations between molecular subtypes, clinicopathological features, and prognosis. METHODS: Ninety-seven gastric cancer cases were classified according to TCGA, ACRG, and integrated classifications using a panel of four molecular markers (EBV, MSI, E-cadherin, and p53). HER2 status and PD-L1 expression were also evaluated. These markers were analyzed using immunohistochemistry (E-cadherin, p53, HER2, and PD-L1), in situ hybridization (EBV and HER2 equivocal cases), and multiplex PCR (MSI). RESULTS: Our results showed that the subtypes presented distinct clinicopathological features and prognosis. EBV-positive gastric cancers were found exclusively in male patients. The GS (TCGA classification), MSS/EMT (ACRG classification), and E-cadherin aberrant subtype (integrated classification) presented the Lauren diffuse histology enrichment and tended to be diagnosed at a younger age. The MSI subtype was associated with a better overall survival across all classifications (TCGA, ACRG, and integrated classification). The worst prognosis was observed in the EBV subtype (TCGA and integrated classification) and MSS/EMT subtype (ACRG classification). Discussion/Conclusion. We reported a reproducible and affordable gastric cancer subtyping algorithms that can reproduce the recently recognized TCGA, ACRG, and integrated gastric cancer classifications, using techniques available in routine diagnosis. These simplified classifications can be employed not only for molecular classification but also in predicting the prognosis of gastric cancer patients.

Microsatellite Instability Analysis in Gastric Carcinomas of Moroccan Patients.

Aim: To investigate correlations between microsatellite instability (MSI) and the phenotype, clinicopathological features, and overall survival (OS) in Moroccan gastric cancer (GC) patients. We evaluated the mutation frequency of 22 MSI-target genes in MSI-positive tumors. Materials and Methods: MSI evaluation were performed for 97 gastric tumors by multiplex polymerase chain reaction (PCR) using a panel of five quasimonomorphic mononucleotide repeat markers (NR27, NR21, NR24, BAT25, and BAT26). The mutation profiles of 22 MSI-target genes were assessed by multiplex PCR and genotyping. Kaplan-Meier curves, the log-rank test, and the Cox proportional hazard regression model were used to conduct survival analyses. Results: Microsatellite stable (MSS) status was observed in 77/97 (79.4%) gastric cancer samples, MSI-Low in 7 (7.2%) samples, and MSI-High (MSI-H) in 13 (13.4%) cases. The MSI-H phenotype was significantly associated with older age (p = 0.004), tumor location (p < 0.001), and intestinal-type of Lauren classification (p < 0.001). Among the 22 MSI target genes analyzed, the most frequently altered genes were HSP110 (84.6%), EGFR (30.8%), BRCA2 (23.1%), MRE11 (23.1%), and MSH3 (23.1%). Multivariate analysis revealed the MSS phenotype (Hazard ratio, 0.23; 95% confidence interval, 0.7-7.4; p = 0.014) as an independent indicator of poor prognosis in our population. Conclusions: This study is the first analysis of MSI in Moroccan GC patients. MSI-H GCs have distinct clinicopathological features and an improved OS. We have identified candidate target genes altered in MSI-positive tumors with potential clinical implications. These findings can guide immunotherapy designed for Moroccan GC patients.

Implication of Microsatellite Instability Pathway in Outcome of Colon Cancer in Moroccan Population.

BACKGROUND: Tumors with microsatellite instability (MSI tumors) have distinct clinicopathological features. However, the relation between these tumor subtypes and survival in colon cancer remains controversial. The aim of this study was to evaluate the overall survival (OS) in patients with MSI phenotype, in FES population. METHODS: The expression of MMR proteins was evaluated by immunohistochemistry for 330 patients. BRAF, KRAS, and NRAS mutations were examined by Sanger sequencing and pyrosequencing methods. The association of MSI status with a patient's survival was assessed by the Kaplan-Meier method and log-rank test. RESULTS: The mean age was 54.6 years (range of 19-90 years). The MSI status was found in 11.2% of our population. MSI tumors were significantly associated with male gender, younger patients, stage I-II, right localization, and a lower rate of lymph node and distant metastasis. The OS tends to be longer in MSI tumors than MSS tumors (109.71 versus 74.08), with a difference close to significance (P = 0.05). CONCLUSION: Our study demonstrates that MSI tumors have a particular clinicopathological features. The results of survival analysis indicate that the MSI status was not predictive of improved overall survival in our context with a lower statistical significance (P = 0.05) after multivariate analysis.

EWSR1 Rearrangement and CD99 Expression as Diagnostic Biomarkers for Ewing/PNET Sarcomas in a Moroccan Population.

Ewing sarcoma/primitive neuroectodermal tumor (Ewing/PNET sarcomas or EPS) are a group of round cell tumors. Malignant round cell tumors form a large and diverse group that includes rhabdomyosarcoma, synovial sarcoma, non-Hodgkin's lymphoma, neuroblastoma, hepatoblastoma, Wilm's tumor, desmoplastic small round cell tumor, and other morphologically similar entities. Differential diagnosis of Ewing sarcoma/primitive neuroectodermal tumor (Ewing/PNET sarcomas or EPS) is difficult. In addition to morphology and immunohistochemistry (IHC), differential diagnosis of these tumors is based on molecular analysis of the EWSR1 gene rearrangement using fluorescent in situ hybridization (FISH) technique. We investigated the diagnostic value of combined CD99 immunostaining and EWSR1 t(22q12) alteration using a dual-color, break-apart rearrangement probe in forty-one formalin-fixed paraffin-embedded (FFPE) tissue samples from pediatric and adult patients diagnosed with EPS. IHC was performed in all cases using the CD99 antibody and showed a positivity of 92.7% in the enrolled cases (38/41) followed by FISH analysis where 48.8% of the cases (20/41) were rearranged. Sensitivity and specificity for IHC assays were 88% and 58%, respectively. Notably, FISH had a sensitivity of 100% and a specificity of 87%. In addition, CD99 positivity was found to correlate with EWSR1 rearrangement (p < 0.05). This report shows that FISH has better sensitivity and specificity than IHC in the Moroccan population, and supports its combination with CD99 immunostaining as diagnostic biomarkers for this rare malignant entity."

Astroblastoma - a rare and challenging tumor: a case report and review of the literature.

BACKGROUND: Astroblastoma is a controversial and an extremely rare central nervous system neoplasm. Although its histogenesis has been clarified recently, controversies exist regarding its cellular origin and validity as a distinct entity. Because of its extreme rarity and because its common features are shared with other glial neoplasms, this tumor is prone to misdiagnosis and remains challenging not only in terms of diagnosis and classification but also in the subsequent management. This case report describes a new case of astroblastoma. It discusses clinical, radiologic, pathological, and therapeutic features and differential diagnosis of this rare neoplasm, with a review of the recent literature. CASE PRESENTATION: We report the case of an 8-year-old Moroccan girl who presented with a 1-year history of epileptic seizure, headache, and decreased visual acuity. Cranial magnetic resonance imaging revealed a right occipito-temporal mass. A tumor resection was performed and histological examination combined with immunohistochemical study confirmed the diagnosis of low-grade astroblastoma. CONCLUSIONS: Astroblastoma is a very rare primary brain tumor. Its diagnosis is often challenging because of the astroblastic aspects that can be found in astrocytic tumors, in ependymomas, and in non-neuroepithelial tumors. Considerable confusion surrounds its histogenesis and classification. The low incidence rate makes it difficult to conduct studies to examine tumor characteristics.

The Assessment of HER2 Gene Status by Fluorescence In Situ Hybridization in Invasive Breast Carcinomas With Equivocal HER2 Immunostaining: Experience From a Single Institution.

BACKGROUND: A subset of breast carcinomas harbors overexpression of the human epidermal growth factor receptor 2 (HER2). Fluorescence in situ hybridization (FISH) should be performed in breast carcinomas with equivocal HER2 immunostaining (immunohistochemistry [IHC] HER2 2+). The aim of our study is to investigate clinicopathologic factors associated with HER2 status in breast invasive carcinomas with IHC HER2 2+ through FISH analysis. METHODS: This is a retrospective study including the FISH analysis of 111 patients with invasive breast carcinomas with equivocal HER2 immunostaining. RESULTS: The mean age was 49.51 ± 10.48 years, and invasive breast carcinoma of no special type was the most histological type in our study (96.4%). Most patients had tumors positive for hormones receptors (88.2% positive for estrogen receptor and 81.4% for progesterone receptor). On FISH, the HER2 amplification rate was 22.5%. There was no significant association of HER2 status with any clinicopathologic factors ( P > .05). CONCLUSIONS: Our study shows that there are no reliable clinicopathologic factors to predict the HER2 status in breast tumors with equivocal HER2 immunostaining, supporting the necessary usage of FISH in such circumstances.

EGFR Amplification and IDH Mutations in Glioblastoma Patients of the Northeast of Morocco.

Glioblastomas are the most frequent and aggressive primary brain tumors which are expressing various evolutions, aggressiveness, and prognosis. Thus, the 2007 World Health Organization classification based solely on the histological criteria is no longer sufficient. It should be complemented by molecular analysis for a true histomolecular classification. The new 2016 WHO classification of tumors of the central nervous system uses molecular parameters in addition to histology to reclassify these tumors and reduce the interobserver variability. The aim of this study is to determine the prevalence of IDH mutations and EGFR amplifications in the population of the northeast region of Morocco and then to compare the results with other studies. Methods. IDH1 codon 132 and IDH2 codon 172 were directly sequenced and the amplification of exon 20 of EGFR gene was investigated by qPCR in 65 glioblastoma tumors diagnosed at the University Hospital of Fez between 2010 and 2014. Results. The R132H IDH1 mutation was observed in 8 of 65 tumor samples (12.31%). No mutation of IDH2 was detected. EGFR amplification was identified in 17 cases (26.15%). Conclusion. A systematic search of both histological and molecular markers should be requisite for a good diagnosis and a better management of glioblastomas.

[Fanconi anemia at the University Hospital (CHU) Hassan II of Fez: about 6 cases]. / Anémie de fanconi au CHU Hassan II Fès: à propos de 6 observations.

Fanconi anemia is a recessive disorder associated with chromosomal instability. It is marked by phenotypical heterogeneity which includes medullary deficiency, a variable malformation syndrome, a predisposition to develop acute leukaemias myéloïdes (ALM) and a cellular over-sensitiveness with the agents bridging the ADN. The diagnosis is based on the abnormal increase in the rate of spontaneous breaks chromosomal but especially and in a specific way, on a clear increase in these chromosomal breaks in the presence of bifunctional alkylating agents, which is the case in our six patients. Genetic counseling is that available for autosomal recessive diseases. We report our initial observations conducted at the University Hospital (CHU) Hassan II of Fez confirmed by the detection of a large chromosomal instability after culture with Mitomycin C compared to a normal control group. The purpose of this study was to update our knowledge of Fanconi anemia genes and to highlight the role of cytogenetics in its diagnosis and the genetic counseling for better management of affected children and their families.

[Lynch syndrome: case report and review of the literature]. / Syndrome de Lynch: à propos d'un cas et revue de la litterature.

Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) is the most common form of hereditary colorectal cancers. It increases cancer susceptibility, the risk of colorectal cancer in first-degree, endometrial cancer in women, and to a lesser extent, other cancers (ovarian, small bowel, stomach, urinary tract and hepatobiliary). Thus, the cumulative risk of developing colorectal cancer or endometrial cancer at the age of 80 years rises to 20 and 40% respectively. These cancers are characterized by a positive family history, their occurrence at an early age, and by the development of metachronous cancers in the same individual. This syndrome is transmitted in an autosomal dominant manner. The genes whose alteration is associated with the presence of an HNPCC belong to the family of DNA mismatch repair genes (DNA mismatch repair or MMR): MSH2, MLH1, and MSH6 are involved, in decreasing order of frequency, in 35%, 25% and 2% of cases respectively. Colonoscopic and gynecological monitoring is recommended for patients with a constitutional mutation in MSH2, MLH1 or Msh6 genes. We report one of the first moroccan case with Lynch syndrome whose constitutional mutation in the MLH1 gene was identified in a family member with colon cancer. In reply to the inquiry ofother healthy family members, a presymptomatic diagnosis was made allowing to formulate an appropriate monitoring strategy. Our study aims to highlight the role of oncogenetics in the management of patients with cancer and their families.

Prevalence of IDH1/2 Mutations in Different Subtypes of Glioma in the North-East Population of Morocco.

BACKGROUND: Genetic alterations in gliomas have increasing importance for classification purposes. Thus, we are especially interested in studying IDH mutations which may feature potential roles in diagnosis, prognosis and response to treatment. Our aim was to investigate IDH mutations in diffuse glioma patients diagnosed in university hospital centre of Fez in Morocco. MATERIALS AND METHODS: IDH1 codon 132 and IDH2 codon 172 were direct-sequenced in 117 diffuse glioma samples diagnosed and treated in University Hospital Hassan II between 2010 and 2014. RESULTS: The R132H IDH1 mutation was identified in 43/117 tumor samples and R172K IDH2 mutation was detected in only one anaplastic oligodendroglioma. IDH mutations were observed in 63.2% of astrocytomas, 73.3% of diffuse oligodendrogliomas and 12.90% of glioblastomas. CONCLUSIONS: Our results confirmed other studies published earlier for other populations with some small discrepancies.

Epigenetics could explain some Moroccan population colorectal cancers peculiarities: microsatellite instability pathway exploration.

BACKGROUND: Colorectal Cancers (CRC) are one of the most common malignancies in the world. Their incidence in Morocco, between 2005 and 2007, was 5.6 for 100000 inhabitants, which is very low compared to what found in developed countries. In addition, CRCs show a high frequency of rectal localizations, and occurs in a younger population in Morocco compared to what found in developed countries. The purpose of this study is to confirm these CRC peculiarities in Morocco and try to explain them by exploring the microsatellite instability molecular pathway. METHODS: This is a prospective observational study conducted since January 2010, including 385 patients admitted in Hassan II University Hospital of Fez. We collected clinical, radiological and pathological data. We investigated the expression of mismatch repair (MMR) proteins in 214 patients and BRAF gene mutations in 159 patients. RESULTS: Mean age was 55.08 +/- 15.16 years. 36.5% of patients were less than 50 years old and 49.3% of tumors were localized in the rectum. Loss of MMR protein expression was observed in 11.2% of cases. It was independently associated with individual or family history of cancer belonging to Hereditary Non-Polyposis Colorectal Cancer (HNPCC) spectrum (p = 0.01) and proximal localization (p = 0.02). No BRAF mutation was detected in all cases. CONCLUSIONS: These results confirm the high occurrence of CRCs to young patients and the high frequency of rectal localizations in Moroccan population. They mostly show an absence of BRAF mutation, supposing a rarity of MLH1 promoter hypermethylation pathway, which may even partially explain the CRC peculiarities in our context. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5868184711716884.

Prevalence of molecular subtypes and prognosis of invasive breast cancer in north-east of Morocco: retrospective study.

BACKGROUND: Breast carcinoma is known as a heterogeneous disease because gene expression analyses identify several subtypes and the molecular profiles are prognostic and predictive for patients. Our aim, in this study, is to estimate the prevalence of breast cancer subtypes and to determine the relationship between clinico-pathological characteristics, overall survival (OS) and disease free survival (DFS) for patients coming from north-east of Morocco. METHODS: We reviewed 366 cases of breast cancer diagnosed between January 2007 to June 2010 at the Department of pathology. Age, size tumor, metastatic profile, node involvement profile, OS and DFS were analyzed on 181 patients. These last parameters were estimated by Kaplan-Meier analysis and log-rank test to estimate outcome differences among subgroups. RESULTS: The average age was 45 years, our patients were diagnosed late (57% stage III, 17.5% stage IV) with a high average tumor size. Luminal A subtype was more prevalent (53.6%) associated with favorable clinic-pathological characteristics, followed by luminal B (16.4%), Her2-overexpressing (12.6%), basal-like (12.6%) and unclassified subtype (4.9%).Survival analysis showed a significant difference between subtypes. The triple negative tumors were associated with poor prognosis (49% OS, 39% DFS), whereas the luminal A were associated with a better prognosis (88% OS, 59% DFS). The luminal B and the Her2-overexpressing subtypes were associated with an intermediate prognosis (77% and 75% OS, and 41% and 38% DFS respectively). CONCLUSION: This study showed that molecular classification by immunohistochemistry was necessary for therapeutic decision and prognosis of breast carcinoma. The luminal A subtype was associated with favorable biological characteristics and a better prognosis than triple negative tumors that were associated with a poor prognosis and unfavorable clinic-pathological characteristics.

Correlates of HPV: a cross-sectional study in women with normal cytology in north-central Morocco.

INTRODUCTION: Epidemiological studies have shown the association between risk of developing cervical cancer and the persistence of high-risk papillomavirus types in addition to some co-factors. However, little is known about co-factors associated with human papillomavirus (HPV) infection, especially in developing countries. This study aims to determine HPV status and associated risk factors in women with normal cytology living in the north-central area of Morocco. METHODOLOGY: From February 2007 to December 2008, a total of 925 women consulting in the gynaecological department of Fez University Hospital were asked about sociodemographic characteristics and reproductive and sexual health. Cervical samples were collected for cytological examination and HPV DNA detection. Data collected from 751 women with normal cytology were used in this study to assess the correlation between HPV infection and potential risk factors. RESULTS: High prevalence of HPV infection was detected (42.5%). The highest infection rate was observed in women aged > 45 years and in those with history of abortion (OR:3.76; 95%CI[1.77-7.98]) fibroma, polyp or cysts (OR:1.68; 95%CI[1.07-2.65]). No significant association was detected with other reproductive health and risk factors including oral contraception. CONCLUSION: In spite of the insignificant association of HPV infection with age, health authorities should seriously consider and implement strategies to increase and maintain a cervical cancer screening programme in women aged 45 and above. More attention must be given to women with gynaecological history (abortion, fibroma, polyp or cysts) since these events may be predictors of HPV infection. Investigations on partner sexual behaviour and some specific hygienic habits, especially public Turkish bath use, are needed to clarify the HPV incidence in this region.

Clinicopathological, therapeutic and prognostic features of the triple-negative tumors in moroccan breast cancer patients (experience of Hassan II university hospital in Fez).

INTRODUCTION: Triple-negative breast cancer (TNBC) is defined as a group of breast carcinomas that are negative for expression of hormone receptors (ER, PR) and Her2, we can distinguish between two groups: basal-like (ER-, PR-, Her2-, cytokeratin (CK) 5/6+ and/or Her1+) and unclassified subtype (ER-, PR-, Her2-, Her1- and CK5/6-).The aim of this study is to determine the clinicopathological, histological, therapeutic and prognostic features associated with this type of breast cancer. METHODS: This is a retrospective study of 366 female breast cancer patients, diagnosed between January 2007 and June 2010 at the Department of Pathology. Epidemiological, clinical, histological, therapeutic and evolutive data were analyzed. OS and DFS rates were estimated by Kaplan-Meier analysis and a log-rank test to estimate outcome. RESULTS: A total of 64 women were identified as having TNBC (17.5% of all female breast cancer patients), 12.6% were basal-like, 4.9% were unclassified subtype, with a median age of 45 years. The median histological tumor diameter was 4.3 cm. TNBC were most often associated with a high grade, 49.2% grade III (53% for unclassified subtype, 47.6% for basal-like). Vascular invasion was found in 26.6% of cases (22% for unclassified subtype and 28.3% for basal-like). For the lymph node involvement: 51% had positive lymph nodes, and 22.4% had distant metastases. Neoadjuvant chemotherapy was administered to 18% patients with 26% of complete pathologic response; therefore adjuvant chemotherapy was given to 82%. 98% received anthracycline based regimen and only 30% received taxanes.The Kaplan-Meier curves based showed the lowest survival probability at 3-years (49% of OS, and 39% of DFS). CONCLUSION: TNBC is associated with young age, high grade tumors, advanced stage at diagnosis, difference chemo response compared to other subtypes, and shortest survival. Critical to optimal future management is accurate identification of truly triple negative disease, and adequately powered prospective TNBC trials to establish treatment efficacy and define predictive biomarkers.