Prognostic role of 18F-FDG PET-CT in the prone position in the evaluation of invasive breast carcinoma

Introduction: The objective of this study was to correlate the features of invasive breast carcinoma in 18F-FDG positron emission tomography/computed tomography with histopathological results, findings from other imaging methods, and survival. Methods: This observational single-center study included patients who underwent staging 18F-FDG positron emission tomography/ computed tomography between September 2012 and April 2019; the results were correlated with the findings of other imaging tests and anatomopathological results. Lesions were evaluated for their maximum standardized uptake value on positron emission tomography/computed tomography performed in the prone position. Tumors were classified into three subtypes (luminal, HER2 and triple-negative) based on immunohistochemical analyses. Results: A total of 125 patients with a mean age of 52 years (24­90 years) were analyzed. The primary tumor showed an increased 18F-FDG concentration on positron emission tomography/computed tomography in 122 (97.6%) patients, with a mean maximum standardized uptake value of 7.15 (1.0­32.9 range). The mean maximum standardized uptake value was higher in the triple-negative subtype (11.4; n=24) than in the luminal (6.2; n=89) and HER2 (5.0; n=9) subtypes (p<0.01). Tumors with more aggressive histological and immunohistochemical characteristics showed higher maximum standardized uptake values. Patients with a standardized uptake value greater than 7 in the primary tumor or greater than 6.7 in the axillary lymph nodes had poor overall survival (p=0.03 and p<0.01, respectively). Conclusions: Our study suggests that the maximum standardized uptake value obtained on positron emission tomography/computed tomography in the prone position may correlate with the tumor immunophenotype and overall survival regardless of the treatments performed, and can be used as a prognostic biomarker in invasive breast carcinoma patients

18F-FDG PET/CT helps to find occult carcinoma in a patient with multiple breast masses at magnetic resonance imaging / PET/CT com 18F-FDG ajuda a identificar carcinoma oculto em paciente com múltiplos nódulos mamários na ressonância magnética

52-year-old female patient with diagnosis of invasive carcinoma in the left breast and metastatic lymph node in the right axilla. Magnetic resonance imaging showed multiple breast masses, with four previous negative biopsies in the right breast. 18F-FDG positron emission tomography (PET)/computed tomography (CT) was performed in prone position, dedicated to breast evaluation. It showed increased uptake in a mass in the right breast. After PET/magnetic resonance imaging (MRI) fusion and second-look breast ultrasound, this mass was submitted to percutaneous biopsy, which confirmed a second invasive breast carcinoma and changed patients' treatment. This is an example of how PET/MRI dedicated devices can improve the evaluation of selected breast lesions.

Paciente do sexo feminino, de 52 anos, com diagnóstico de carcinoma invasivo na mama esquerda e linfonodo metastático na axila direita. A ressonância magnética mostrou múltiplos nódulos mamários bilaterais, com quatro biópsias anteriores negativas na mama direita. 18F-FDG PET/tomografia computadorizada (CT) foi realizado em decúbito ventral, dedicada à avaliação das mamas, demonstrou aumento da captação em um nódulo na mama direita. Depois de fusão das imagens do PET/CT com a ressonância magnética (RM) e ultrassonografia direcionada, esta lesão foi submetida à biópsia percutânea, que confirmou um segundo carcinoma invasivo na mama direita, alterando o tratamento. Este é um exemplo de como os dispositivos dedicados de PET/RM podem melhorar a avaliação das lesões mamárias selecionadas.

Magnetic resonance imaging of the breast: role in the evaluation of ductal carcinoma in situ / Papel da ressonância magnética das mamas na avaliação do carcinoma ductal in situ

Abstract Ductal carcinoma in situ (DCIS) is a precursor mammary lesion whose malignant cells do not extend beyond the basement membrane and presents a risk of progression to malignant disease. Its early detection increased with screening mammography. The objective of this study was to review the literature on the main presentations of DCIS on magnetic resonance imaging (MRI), through searches of the Medline/PubMed, Latin-American and Caribbean Center on Health Sciences Information (Lilacs), and Scientific Electronic Library Online (SciELO) databases. DCIS can occur in its pure form or in conjunction with invasive disease, in the same lesion, in different foci, or in the contralateral breast. MRI has a high sensitivity for the detection of pure DCIS, being able to identify the non-calcified component, and its accuracy increases with the nuclear grade of the lesion. The most common pattern of presentation is non-nodular enhancement; heterogeneous internal structures; a kinetic curve showing washout or plateau enhancement; segmental distribution; and restricted diffusion. MRI plays an important role in the detection of DCIS, especially in the evaluation of its extent, contributing to more reliable surgical excision and reducing local recurrence.

Resumo O carcinoma ductal in situ (CDIS) é uma lesão mamária precursora cujas células malignas não ultrapassam a membrana basal e possui risco de evolução para doença maligna. Sua detecção precoce aumentou com a mamografia de rastreamento. O objetivo deste estudo foi realizar uma revisão da literatura sobre as principais apresentações do CDIS na ressonância magnética (RM), utilizando mecanismos de busca na base de dados Medline/PubMed, Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde (Lilacs) e Scientific Electronic Library Online (SciELO). O CDIS pode ocorrer de forma pura ou associado a doença invasiva, na mesma lesão, em focos diferentes e na mama contralateral. A RM possui alta sensibilidade para a detecção do CDIS puro, sendo capaz de identificar o componente não calcificado da doença e sua precisão aumenta com o seu grau nuclear. O padrão de apresentação mais comum é o realce não nodular com padrão interno heterogêneo, curva cinética de lavagem rápida (washout) ou platô, de distribuição segmentar e com restrição na difusão. A RM tem importante papel na detecção do CDIS e, principalmente, na avaliação da sua extensão, contribuindo para uma exérese cirúrgica mais confiável e reduzindo as recidivas locais.