CT images may show gene activity.

One day new tools might allow physicians to view computed tomography (CT) images of a tumor and discern its genetic activity, according to a study that appeared in the May 21 online issue of Nature Biotechnology. Researchers said the tools could allow physicians to obtain the molecular details of a specific tumor or disease without having to do an invasive biopsy procedure.

The new research built on the recent development of DNA microarrays at Stanford University in California. Microarrays are lab tools that screen thousands of genes at a time and have proven to be useful for comparing genetic patterns in diseases, such as cancer, with normal tissue activity.

Researchers devised a way to connect gene activity seen with microarrays to imaging patterns (see figure). This would allow physicians to translate images to gene patterns and, ultimately, to the outcome of the disease process.

The researchers started with approximately 135 basic tumor descriptors and then narrowed down the multitude of traits to the 28 most important diagnostic descriptors, matching those imaging features with a vast stockpile of microarray data generated from human liver cancer samples.

They then compared features from CT images of liver tumors with the gene expression patterns. Once they pinpointed the genomic correlates of the features detected by CT imaging, the researchers found that the tumor's appearance on CT and its behavior on a molecular level had a very strong connection.

Out of approximately 7000 genes in the tumors, the research team was able to consistently associate imaging traits with 75% of the genes.

Researchers acknowledged that they are very far from clinical applications of these tools. However, the strong connections between the imaging features and the molecular gene activity data suggest that this could be a promising research direction.

Inexpensive Ultrasound Scanner Upgrades

A new system will enable health care facilities to inexpensively upgrade their conventional 2-D ultrasound scanners to provide 3-D images.

Three-dimensional ultrasound has enabled advances in many areas of medicine, including fetal research, cardiac imaging and oncology. For example, 3-D ultrasound can provide important information on the structure of tumors, their growth pattern and their blood supply.

Although 3-D technology has been available since the 1990s, it remains prohibitively expensive. Physicians and clinics wishing to upgrade from 2-D to 3-D technology usually have to invest more than $65 000 in new equipment, according to Fraunhofer Technology Development Group in Stuttgart, Germany.

Fraunhofer researchers have succeeded in producing a considerably less expensive solution for physicians that enables conventional 2-D ultrasound scanners to be upgraded to provide 3-D images for as little as $540.

The researchers created the system by fitting ultrasound transducers with inertial sensors that can determine the exact position and orientation of the probe. Specially developed procedures then allow reconstruction of a 3-D image from the data.

The inertial sensors are small, inexpensive semiconductor components that are sensitive to movement in any direction. Such sensors are normally very imprecise, especially when determining equatorial coordinates. However, the special procedures developed by the Fraunhofer engineers enable the exact calculation of spatial coordinates. The margin of error of the sensors, therefore, could be reduced from around 10 degrees to less than 1 degrees. For the first time, a highly accurate, low-cost navigation system is available that can be integrated easily into existing ultrasound scanners.

The new system, which consists of a small device installed with the necessary software, should be available commercially later this year. Fraunhofer developed the system in collaboration with MedCom of Darmstadt, Germany.

NSAIDs May Improve Radiation Therapy

Nonsteroidal anti-inflammatory drugs (NSAIDs) might improve the cancer-killing ability of both radiation therapy and chemotherapy, according to 2 new studies.

Because inflammation is thought to play a role in the development of certain cancers, numerous studies have investigated the role of NSAIDs such as aspirin and celecoxib in cancer prevention. However, few studies have evaluated the relative anticancer activity of different NSAIDs.

In the first study, researchers tested 10 commercially available NSAIDs against head and neck cancer cells. They found that celecoxib and sulindac sulfide, sold as Clinoril sulfide, were particularly effective at killing cancer cells and slowing cancer cell proliferation. Celecoxib was the most effective, killing up to 60% of head and neck cancer cells under the study conditions. None of the other 10 NSAIDs in the study, including aspirin, Aleve and Vioxx, showed effective anticancer activity.

The study, which appeared in the April 5 online issue of Molecular Carcinogenesis, also indicated that celecoxib's and sulindac sulfide's anticancer activity was mediated through cell cycle inhibition and induction of apoptosis and was not related to the drugs' anti-inflammatory properties.

In the second study, researchers showed how celecoxib exerts its anticancer effect by altering protein expression in ways that disrupt the cell cycle and lead to cell death.

Cells go through 3 phases before they divide: the G1 phase, in which the cell grows and makes protein; the S phase, in which the cell makes DNA and replicates its chromosomes; and the G2 phase, in which the cell prepares for division. The cell cycle also contains several well-defined checkpoints where the growing cell stops and "decides" that things are ready to move on to the next stage.

The researchers found that celecoxib specifically kills head and neck cancer cells in the S phase of the cell cycle, in which the cell synthesizes new DNA and replicates its genetic material. This is when cells are most resistant to radiation therapy. Celecoxib's selective killing of cells in the S phase suggests this class of drugs could target the radio-resistant cells and use of the drug together with radiation might provide better tumor control than radiation alone.

The study results also suggest that celecoxib would improve chemotherapy. Although NSAIDs have adverse side effects, including risk of cardiovascular and kidney disease, one researcher suggested that the potential benefits of the drugs outweigh the risks. The second study appeared in the April 15 issue of Cancer Research.

Imaging Abuse and Fraud Costly to Patients, Industry

Waste, fraud and abuse of diagnostic imaging affect patient safety and significantly drive overall health care spending, according to a company that specializes in radiology management.

The growth in radiology procedures has raised concern about the collective impact of waste, fraud and abuse on the overall cost of care, as well as patient exposure to radiation, according to MedSolutions, of Franklin, Tennessee.

The company said that waste is a significant problem in imaging, with direct-to-consumer marketing and the increasing tendency toward aggressive surveillance and treatment of incurable diseases helping to drive the waste.

"Waste is expensive, with unnecessary imaging estimated to cost the country billions, possibly even as high as $10 billion annually," said Gregg P. Allen, M.D., chief medical officer of MedSolutions.

In addition to waste, MedSolutions said fraud and abuse are adding to the overall imaging cost burden. Dr. Allen pointed out that self-referral leads to abuse because there is a clear incentive for physicians to perform imaging studies when the practice will benefit financially from the study being performed. Additionally, the rapid increase of imaging equipment in the outpatient setting, the lack of equipment standardization and the increase in in-office imaging raise additional opportunities for fraud.

MedSolutions provides radiology expertise to help payers and Medicaid programs manage their radiology costs.

Shorter Radiation Therapy Regimen Well Tolerated

Women with breast cancer who receive higher doses of radiation with intensity-modulated radiation therapy (IMRT) each day can reduce their treatment time by 2 weeks without increasing side effects, according to a study in the June 1 issue of the International Journal of Radiation Oncology, Biology and Physics.

Standard radiation therapy for early breast cancer requires daily treatment for 6 to 7 weeks, which is an inconvenience to many women and a barrier for breast conservation for some. Researchers wanted to see how women with breast cancer would tolerate a shorter treatment regimen with an added radiation boost.

In the study, 75 women underwent IMRT for 4 weeks. The women received a slightly higher radiation dose to the entire breast while also receiving a radiation boost to the original lumpectomy site of the breast. Physicians graded the skin toxicity of each patient, with Grade 0 representing no skin toxicity and Grade 9 representing severe toxicity.

At the end of the 4-week treatment period, 65% of the women had Grade 1 skin toxicity and 23% reported a skin toxicity of Grade 2. The other 12% had Grade 0 toxicity.

In the short-term follow-up at 6 weeks, researchers found that all toxicity levels had returned to normal, including the women who had Grade 2 skin toxicity. In addition, the incidence of breast infection was comparable to previous studies of infection rates after conventional treatment.