Ressonância magnética da próstata: uma visão geral para o radiologista* Magnetic resonance imaging of the prostate: an overview for radiologists

O adenocarcinoma prostatico e o segundo tumor em incidencia e mortalidade dentre as neoplasias malignasmasculinas. Para adequada programacao terapeutica e importante a distincao entre tumores confinados aprostata e aqueles com extensao extraprostatica. Diferentes estudos tem demonstrado que a ressonânciamagnetica da prostata com bobina endorretal auxilia no estadiamento local destes pacientes. Este artigoapresenta informacoes sobre a anatomia prostatica, o aspecto tumoral a ressonância magnetica, sinais deextensao tumoral extraprostatica e invasao de vesiculas seminais, sugestoes de protocolo, principios geraise importância da espectroscopia de protons, do estudo perfusional e da difusao, indicacoes da ressonânciamagnetica na investigacao de recidiva pos-operatoria e pos-radioterapia, seu papel na deteccao de lesoessuspeitas em pacientes com suspeita clinico-laboratorial de adenocarcinoma prostatico, alem de apresentaros diagnosticos diferenciais e limitacoes do metodo.Unitermos: Neoplasias da prostata; Adenocarcinoma; Imagem por ressonância magnetica; Estadiamento deneoplasias.Prostate adenocarcinoma is the second tumor in incidence and mortality among malignant neoplasms in men.The differentiation between tumors confined to the organ and those with extraprostatic extension is criticalfor an appropriate therapeutic planning. Different studies have demonstrated that magnetic resonance imagingof the prostate with endorectal coil is useful in the local staging of these tumors. The present article presentsinformation on the prostate gland anatomy, the tumor aspect at magnetic resonance imaging, specific signsof extracapsular extension and seminal vesicles invasion, protocol suggestions, general principles and relevanceof proton spectroscopy, perfusion and diffusion imaging, role of magnetic resonance imaging in thepostoperative and post-radiotherapy detection of local tumor recurrence, and also in the detection of lesionsin patients with clinical/laboratory suspicion of prostate adenocarcinoma. Additionally, the present articledescribes differential diagnoses and limitations of the method.Keywords: Prostate cancer; Adenocarcinoma; Magnetic resonance imaging; Cancer staging.