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Technology Offers Second Look at Cancer Detection

Andreas Campbell tries to stay current with all her required preventative medicine exams and tests. The 63-year-old Vienna resident, formerly from New Jersey, had already scheduled a routine mammogram when she agreed to give the Inova Fair Oaks Hospital's newest machine a try.

The computer-aided detection (CAD) technology, known as Image Checker, reads mammogram film and looks for abnormalities that could be missed by the naked eye. A print out of the machine's reading — a low-resolution image of the breast — marks areas of calcifications and masses, alerting the radiologist to take a closer look at portions of the mammogram.

"I watched as they put the X-rays into the machine, but I didn't understand anything about it," Campbell said. "There were three areas marked that gave me a little angst, but subsequently the radiologist read it and compared it to my X-rays from New Jersey and determined everything was fine."

Campbell said the new machine "absolutely" made her feel more confident about the results of her mammogram.

"I'm very positive toward new technology. Why wouldn't you be?" Campbell said.

THIS YEAR, Inova Health System has added two new machines to its arsenal geared toward helping physicians detect cancer at earlier stages and, thereby, possibly avoiding surgery down the road.

Along with CAD, the health system has begun using a diagnostic machine that fuses a traditional PET (positron emission tomography) scan, which is used to identify changes in body chemistry, with a traditional CT (computerized tomography) scan, which provides an anatomical view of the body's soft tissue, to provide a more detailed "road map" of a person's inner body, said Dr. Karan Lotfi, assistant director of nuclear medicine at Inova Alexandria Hospital and radiologist.

"It joins them together and you have a beautiful road map," Lotfi said. "It's like a magic bullet. It goes right to the abnormality. It only shows you the abnormality. You don't want to see the good stuff."

Clinical tests have so far showed the fusion technology effective in detecting common forms of cancer including lung, colorectal, melanoma, lymphoma, head and neck, esophageal, breast, thyroid and brain cancers, as well as single pulmonary nodules. It is also being studied for its effectiveness in detecting ovarian cancer.

The PET/CT fusion technology shows a CT scan beside a PET scan on a computer screen. The PET scan side might show a glow, which represents the abnormality, but no anatomical information. The CT scan shows the anatomical information, but no glow. When the images are fused, a physician can identify the location of the abnormality with greater accuracy than simply holding the separate scans side-by-side.

"A CT scan is 60 percent to 70 percent sensitive in detecting abnormalities. A PET scan is very sensitive, on the order of 85 percent to 90 percent," Lotfi said. "The PET scan doesn't show the anatomy, just the abnormality. That's why you have to fuse the two together. Doctor's evaluations have became more rigorous with the technology and we're seeing 3 millimeter lesions."

The detail allows doctors to distinguish between possible tumors and harmless scar tissue without the need for a biopsy.

SIMILARLY, the CAD eliminates the need for biopsy or other surgery by better identifying abnormalities in the mammogram. The CAD image shows calcifications, which are typically buildups of calcium, with a triangle and a mass, which could be malignant or benign, as an asterisk. In some cases, the calcification or mass is large enough to be seen on the mammogram film unaided, but not always.

"All it's telling you is to take a closer look at the film," said Chloe Dalton, a radiology and mammogram technician at Inova Fair Oaks Hospital. "Calcifications on film look like white dots. A mass looks more like a tissue that's distorted. I think it's cutting down on the number of biopsies."

In fact, Dr. Deborah Blair, chairman of the Department of Radiology at Inova Fair Oaks, said studies show mammograms are effective at detecting 80 percent of breast cancer. The CAD increases the chances of early detection by 20 percent.

But the machine is not meant to replace a physician's assessment.

"You look at the film first and come to your own conclusions," Blair said. "I do find myself looking at the film and saying, 'I bet that will come up on the CAD.' And it will surprise you on occasion by sending you back to an area that you didn't see anything."

Dalton said the CAD at Fair Oaks runs about 30 cases per day. Without CAD, each case would require a reading by two radiologists. The machine, she said, is like the second pair of eyes.

WHILE BOTH TECHNOLOGIES are new to the area — Inova is believed to be the only health facility with both machines in Northern Virginia, outside of some private practices — both have been around for several years and have been subjected to numerous studies. Karen Schwartz, a spokesperson for Loudoun County Hospital Center, said the facility does not have either machine.

Lotfi, for example, has been using the PET/CT scan fusion technology for more than five years, learning it during a fellowship at the University of Pennsylvania Medical Center.

"There are large bodies of evidence [supporting PET/CT fusion technology] over the course of 10 to 15 years," Lotfi said. "So while the public is just hearing about it, it's been out there. It will become standard in the management of patients with cancer."

The CAD has also been available for a while before coming to Inova, said Blair, with the most recent major study being completed in 2001.

"Some things are gimmicks, but to me this is not," Blair said. "Everyone I know is so happy knowing a computer is looking at [the mammogram results]."

Blair said study results have been so positive toward the CAD, that it is now covered by Medicare.

"Medicare pays for these because lumpectomies are more expensive," Blair said.

CAD is available at Inova Fair Oaks Hospital, while the PET/CT fusion technology is being used at Inova Alexandria and Fairfax hospitals.