Câncer de mama e fator de Von Willebrand

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Expressão de marcadores de células-tronco tumorais em carcinomas mamários basais e pentanegativos : estudo em uma série de tumores triplonegativos

INTRODUÇÃO: o câncer de mama é uma doença heterogênea. Há necessidade de critérios diagnósticos e prognósticos mais refinados. O emprego da imunohistoquímica, através do painel prognóstico, fez despontar a figura do carcinoma triplonegativo e, da mesma forma, a histogenética trouxe à evidência o carcinoma basal. Paralelamente, o conhecimento sobre a origem biológica das neoplasias e da sua heterogeneidade vem sendo acentuadamente debatido através do tema das células-tronco tumorais. OBJETIVOS: investigar a prevalência de carcinomas basais e pentanegativos, numa amostra de carcinomas triplonegativos, e estabelecer associações com a expressão de células-tronco tumorais nestes tumores. Verificar diferenças entre estes subtipos com as variáveis clinicopatológicas. MÉTODOS: 94 carcinomas mamários triplonegativos foram testados para CK5/6, HER1, CD44 e CD24. As expressões desses marcadores por imuno-histoquímica automatizada foram avaliadas através de escore simples de positividade (porcentagem de células) e correlacionadas com os dados clínico-patológicos e análise de sobrevivência. RESULTADOS: carcinomas basais apresentam maior grau tumoral que carcinomas pentanegativos (p=0,004). A negatividade para CD44 (p=0,007) e o perfil CD44- CD24+ (p=0,013) foram associados com maior invasão vascular entre carcinomas triplonegativos. A expressão de CD44 foi associada aos carcinomas basais (p=0,007). O perfil CD44-CD24-/low foi associado aos carcinomas pentanegativos (p=0,04). Nenhuma das variáveis em estudo foi associada com os desfechos clínicos. CONCLUSÃO: Carcinomas mamários basais e pentanegativos são subtipos tumorais bastante próximos. Nosso estudo é o primeiro desenhado especificamente para avaliar a presença células tronco-tumorais mamárias entre carcinomas basais e pentanegativos, onde o perfil CD44-CD24-/low foi associado ao subtipo pentanegativo, e o perfil CD44-CD24+ à invasão vascular, resultados que merecem confirmação por histogenética em estudos de maior porte.INTRODUCTION: Breast cancer is a heterogeneous disease, and there is a need for more refined diagnostic and prognostic criteria. Immunohistochemistry, as a breast prognostic panel, has given rise to triple-negative carcinoma, as well as histogenetics highlighted basal carcinoma. Concomitantly, the understanding of the biological origins of neoplasia and its heterogeneity has been strongly debated through the theme of cancer stem cells. OBJECTIVES: To investigate the prevalence of basal and penta-negative carcinomas in a sample of triple-negative carcinomas and to establish associations with cancer stem cells (CD44/CD24 expression profiles) and the clinicopathological variables within these tumors. METHODS: Ninety-four triplenegative breast carcinomas were tested for CK5/6, HER1, CD44 and CD24. The expression of these markers was evaluated by automated immunohistochemistry using a simple positivity score (percentage of cells) and was correlated with the clinicopathological and survival analysis data. RESULTS: Basal carcinomas had higher tumor grades than penta-negative carcinomas (p=0.004). CD44 negativity (p=0.007) and the CD44-CD24+ phenotype (p=0.013) were associated with increased vascular invasion amongst the triple-negative carcinomas. CD44 expression was associated with basal carcinomas (p=0.007). The CD44-CD24-/low phenotype was associated with penta-negative carcinomas. None of the variables in the study were associated with clinical outcome. CONCLUSION: Basal and penta-negative breast carcinomas are closely related tumor subtypes. Our study is the first to be specifically designed to assess the presence of breast cancer stem cells in basal and pentanegative carcinomas. The CD44-CD24-/low phenotype was associated with the pentanegative subtype, and the CD44-CD24+ phenotype was associated with vascular invasion. These results require histogenetic confirmation in larger studies

Comparison between preoperative and intraoperative injection of (99m)Tc Dextran-500 for sentinel lymph node localization in breast cancer

A retrospective study was conducted from a review of the medical records of patients with early-stage, invasive breast cancer who underwent surgical treatment and sentinel node biopsy with a radiotracer from January 2008 to August 2012 at a single institution (221 patients included). The patients were grouped according to the time of 99mTc Dextran-500 injection, which was preoperatively (with lymphoscintigraphy) (81 patients) or intraoperatively (140 patients). The purpose of the report is to compare the results of sentinel node biopsy of early-stage breast cancer patients who were subjected to intraoperative 99mTc Dextran-500 injections with the patients who received preoperative injections. The following parameters were analyzed: clinical tumor staging, histological and pathological results, size and number of tumor foci, peritumoral vascular invasion, number of lymph nodes removed, size of lymph node metastasis and hormone receptor expression.There were no differences in sentinel lymph node localization whether 99mTc Dextran-500 was injected preoperatively or intraoperatively