MRI for hepatocellular carcinoma: a primer for magnetic resonance imaging interpretation

Diagnostic efficacy of contrast-enhanced ultrasound, dynamic contrast-enhanced MRI combined with tumor markers AFP and DCP for primary hepatocellular carcinoma

The purpose of this study was to investigate the diagnostic efficacy of contrast-enhanced ultrasound (CEUS) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) combined with tumor markers alpha-fetoprotein (AFP) and des-γ-carboxyl prothrombin (DCP) for primary hepatic carcinoma (PHC). A total of 70 patients with PHC (PHC group), 42 patients with liver cyst (benign liver disease group (BLDG)) and 30 healthy people (healthy group (HG)) were selected as the research objects. CEUS and DCE-MRI were performed by American GE Vivid E9 color Doppler ultrasound system and Siemens 1.5T magnetic resonance imager, respectively. The levels of AFP and DCP were detected by ABBOTT i2000SR chemiluminescence instrument and enzyme-linked immunoassay (ELISA), respectively. In DCE-MRI examination, the portal phase and prolonged phase were mostly low signal in T1-weighted imaging (T1WI) sequence, and arterial phase was mostly high signal in T2WI sequence. In CEUS, most lesions showed hyper-enhancement in arterial phase, and hypo-enhancement in portal phase and delayed phase. AFP and DCP levels in PHC group were significantly higher than that in BLDG group and HG group. There were statistically significant differences among the three groups. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of combined diagnosis were statistically significant when compared with CEUS, AFP and DCP alone and either AFP or DCP positive. CEUS, DCE-MRI combined with tumor markers AFP and DCP have high sensitivity, specificity and accuracy in the diagnosis of PHC, which can more accurately diagnose the lesion type, provide basis for further treatment, and is worthy of clinical application.

Magnetic Fields and Cancer: Epidemiology, Cellular Biology, and Theranostics

Humans are exposed to a complex mix of man-made electric and magnetic fields (MFs) at many different frequencies, at home and at work. Epidemiological studies indicate that there is a positive relationship between residential/domestic and occupational exposure to extremely low frequency electromagnetic fields and some types of cancer, although some other studies indicate no relationship. In this review, after an introduction on the MF definition and a description of natural/anthropogenic sources, the epidemiology of residential/domestic and occupational exposure to MFs and cancer is reviewed, with reference to leukemia, brain, and breast cancer. The in vivo and in vitro effects of MFs on cancer are reviewed considering both human and animal cells, with particular reference to the involvement of reactive oxygen species (ROS). MF application on cancer diagnostic and therapy (theranostic) are also reviewed by describing the use of different magnetic resonance imaging (MRI) applications for the detection of several cancers. Finally, the use of magnetic nanoparticles is described in terms of treatment of cancer by nanomedical applications for the precise delivery of anticancer drugs, nanosurgery by magnetomechanic methods, and selective killing of cancer cells by magnetic hyperthermia. The supplementary tables provide quantitative data and methodologies in epidemiological and cell biology studies. Although scientists do not generally agree that there is a cause-effect relationship between exposure to MF and cancer, MFs might not be the direct cause of cancer but may contribute to produce ROS and generate oxidative stress, which could trigger or enhance the expression of oncogenes.