Frequência do vírus Epstein-barr (ebv) em pacientes com câncer de mama do serviço de mastologia de um hospital do estado do Ceará

Abstract

Breast cancer is the leading cause of cancer death among women worldwide. Despite having good prognosis when diagnosed and treated properly, breast cancer mortality rates remain high in Brazil. The etiology of breast cancer is multifactorial and some risk factors are described, such as age, family and personal history of cancer, factors linked to endocrine aspects , among others. However, by 50 to 80% of cases none of these factors is identified, suggesting the existen ce of another one . S tudies point to an association of breas t cancer with the Epstein - Barr V irus (EBV), but the studies are controversial. Thus, this study aimed to verify the presence of EBV, using in situ hybridization in 75 patients diagnosed with invasi ve breast carcinoma, from the Mastology Clinic of the Maternity School Assis Chateaubriand. For molecular classification, E R , PR, HER2, Ki67, TP 53, CK5/ 6 and CK8 /18 markers were detected by immunohistochemistry. In this study, the median age of patients wa s 55 years, of which 28% were aged up to 45 years. Only 8,7 % of the tumors were diagnosed early. More advanced stage of degrees and lymph node involvement characterized this sample. Most tumors express luminal cytokeratins markers, hormone receptors and ma rker of cell proliferation (Ki67). Moreover, TP53 and HER2 were present in a minor fraction of tumors. EBV was positive in only 6.67% of the cases in which the presence of the virus was restricted to a few nuclei of tumor cells. The luminal B subtype was t he most common, followed by luminal A. TP53 was more frequent in tumors of the basal - like subtype (75%), significantly differing from the luminal A tumors ( 16,7 %) (p = 0.0 3 ) regardless of age. Among the patients up to 45 years, all triple negative (b asal - l ike and n ormal - like) subtype tumors were T P53 positive, while a low frequency was found in luminal A and B subtypes with a statistical difference between triple negative (100%) and luminal A ( 14,3 %) (p = 0.0 2 ), triple negative and luminal B (1 6 . 7 %) (p = 0. 0 2 ) , between basal - like (100%) and luminal A (p = 0.0 4 ) and basal - like and luminal B (p = 0.04) . The TP53 frequency did not differ significantly between the molecular subtypes in patients over 45 years. Comparing the age groups, it is interesting to note t hat in triple negative subtype tumors in patients under 45 years old TP53 was statistically more frequent than in patients over 45 years old compared with luminal B, while in luminal B tumors, TP53 was more frequent in patients over 45 years old. In conclu sion, despite the presence of EBV observed, the small number of cases and the weak positivity does not allow to say that this is an etiological factor for the development of breast cancer n either the association of their presence with some molecular subtyp e. However, it is important to note that the virus was investigated based on your profile latency considering the EBER expression and these data raise the addition of other targets for studying the real participation of the virus. Furthermore, it is intere sting to note the importance of TP53 as a marker of differential triple negative tumors in women below 45 years.