MRS reveals prostate cancer biochemical profile
MR spectroscopy shows promise for use in locating prostate cancer and determining tumour aggressiveness, in order to help guide treatment planning. That's the conclusion of a study from Massachusetts General Hospital (Boston, MA). The research team used a 7T whole-body MR scanner to analyse five cancerous prostate glands removed during prostatectomy. After scanning, the prostate glands were examined by standard histological techniques (Sci. Transl. Med. 2 16ra8).
Spectroscopic analysis revealed the proportions of various metabolites associated with the presence of cancer and accurately identified the location of malignant tissue. A malignancy index calculated from the MR spectra linearly correlated with lesion size and demonstrated a 93–97% overall accuracy for detecting prostate cancer lesions. "Collectively analysing all of the metabolites measurable with a 7T MR scanner maps out prostate cancer in a way that cannot be achieved by any other current radiological test or by analysing changes in a single metabolite," said senior author Leo L Cheng. Following further studies to verify these results, the team hopes to move into clinical trials within a year or two.
Mobile phones could protect against Alzheimer's
A study in mice has provided surprising evidence that long-term exposure to electromagnetic waves – as associated with mobile phone use – may protect against, and even reverse, Alzheimer's disease. A research team from the University of South Florida (Tampa, FL) examined 96 mice, most of which were genetically altered to develop beta-amyloid plaques – a hallmark of Alzheimer's disease – as they aged (J. Alzheimers Dis. 19 191).
Mice were exposed to the field generated by standard mobile phone use for two one-hour periods each day, for 7–9 months. Exposing old Alzheimer's mice to electromagnetic waves erased brain deposits of beta-amyloid. If exposure was started when the mice were young, protein build-up was prevented and cognitive ability protected. Months of exposure even boosted the memories of normal mice to above-normal levels. The researchers concluded that electromagnetic field exposure could be an effective, non-invasive way to prevent and treat Alzheimer's disease in humans. They are currently evaluating whether different frequencies and field strengths will produce more rapid and greater cognitive benefits.
RF ablation reduces pain from bone metastases
Image-guided radiofrequency (RF) ablation can significantly reduce pain from bone metastases, according to a recent American College of Radiology Imaging Network study. The study examined 55 patients with a single painful bone metastasis, treated with CT-guided RF ablation of the tumour. The results showed statistically significant pain reduction one and three months after treatment. The procedure was found to be safe with few adverse events (Cancer 116 989).
While 30–70% of new cancer patients will develop a bone metastasis, current pain treatments are not effective for all of these patients. "It is clear that improved palliative treatments must be identified to address the needs of these great many patients," said principal investigator Damian Dupuy, professor of diagnostic imaging at the Warren Alpert Medical School of Brown University (Providence, RI). "RF ablation is widely available and can be performed in a single outpatient session. Also, unlike many other cancer pain management treatments, it can be repeated and maintain similar results."
Ultrasound helps treat heart disorder without X-rays
A team at the University of Virginia (Charlottesville, VA) has developed an X-ray-free method for treating atrial fibrillation. To regulate the heart's rhythm, doctors commonly perform a catheter ablation, using X-ray fluoroscopy to guide the catheter to the affected area of the heart. The researchers devised a technique based on an ultrasound catheter (intracardiac echocardiography) and electro-anatomic mapping that can be used instead (Circ. Arrhythm. Electrophysiol. 2 611).
The ultrasound catheter provides high-resolution images of the heart, while the mapping system displays a 3D image of the heart and catheter, and allows physicians to record precise location points along the catheter's path. The technique has been tested in a pilot study of 21 patients. "Larger studies are needed to confirm the safety of the procedure, but the concept that you can perform complex electrophysiology procedures without any use of X-ray is outstanding," noted Brian Annex, chief of the UVA Division of Cardiology. "This research is a ground-breaking step in our efforts to minimize radiation exposure to all patients."
Magnetic nanoparticles extract circulating cancer cells
Scientists at the Georgia Institute of Technology (Atlanta, GA) have further developed a potential cancer treatment that uses magnetic nanoparticles to remove ovarian cancer cells from the body. The treatment, previously tested in mice, has now been tested using samples from human cancer patients (Nanomedicine doi: 10.1016/j.nano.2009.11.003).
The technique reduces the spread of ovarian cancer cells to other organs by attaching nanoparticles to the cancer cells, and then applying a magnet. The idea is to filter the peritoneal fluid or blood and remove any free floating cancer cells, thus preventing the continued metastatic spread. The next step is to test how well the scheme can increase survival in live animal models. If successful, the researchers plan tests on humans.
Paediatric PET requires child-specific doses
While established guidelines exist for administering radiopharmaceuticals to adults undergoing PET, there is little guidance for administering paediatric doses. To address this shortcoming, researchers at the Children's Hospital of Philadelphia and the University of Pennsylvania (Philadelphia, PA) have collated data to help provide clear dose guidelines for paediatric PET exams. The researchers analysed data from 73 patients weighing between 11.5 and 91.4 kg. When following a weight-proportional injection protocol, the quality of PET images improved with decreasing weight (J. Nucl. Med. 51 293).
"These findings mean that PET can be used in children with methods that are even more patient-specific than those currently employed," said Roberto Accorsi, lead author of the study. "The results of this study show that, due to children's relatively small size and light weight, it is possible to reduce radiological dose (or scan time) while preserving image quality as compared to PET imaging in adults. Minimizing exposure to radiation is important to all patients, but especially for young children."
NPL phantoms validate optical coherence tomography
Optical coherence tomography (OCT) is a high-resolution, non-ionizing technique for detecting changes in tissue structure that could indicate the early stages of cancer. To help ensure the precision of OCT imaging, the UK's National Physical Laboratory (NPL) has developed a "point-spread phantom" for OCT quality assurance. The phantoms are translucent cylinders of resin containing particles designed to reflect light in a specific way. By viewing the phantom with an OCT system and analysing the image with NPL software, users can be certain that it is producing accurate images.
The phantom will also allow manufacturers of OCT technology to meet the necessary standards to bring their products to market. NPL is now running trials with companies before bringing the phantom to market, with Michelson Diagnostics the first UK firm to use it to validate the accuracy of their machines.