THURSDAY, July 22, 2004 (HealthDayNews) -- Advances in the field of radiology are making both detection and treatment of breast cancer more efficient and more effective.
That was the general message of a telebriefing Thursday, sponsored by the Radiological Society of North America, which brought together several experts in the field.
Mammography itself has improved detection rates -- and therefore survival rates -- over the past several decades. More women than ever are being screened: In 1987, 29 percent of American women surveyed said they received a mammogram every two years, vs. 70 percent in 2000. In 2000, 63 percent of American women said they were going for a mammogram every year, said Dr. Steve Feig, a professor of radiology at the Mt. Sinai School of Medicine in New York City.
This has translated into more early cancers being diagnosed, which in turn has translated into better survival odds. "A woman with invasive carcinoma today is 39 percent less likely to die from her disease than she would have been back in the 1980s, and that is attributable to screening mammography," Feig stated.
Still, up to 15 percent of breast cancers are missed by mammography, and 30,000 women die of the disease every year in the United States. "We still have a long way to go," said Dr. Etta Pisano, a professor of radiology and biomedical engineering and chief of breast imaging at the University of North Carolina Medical School in Chapel Hill.
Pisano is principal investigator of a large study (almost 50,000 women) comparing digital mammography with film mammography. The results, expected to be available in January, will also include information on cost-effectiveness, quality of life and differences in equipment.
Several other studies are looking at other alternatives or enhancements to mammography, such as ultrasound and magnetic resonance imaging (MRI). "This is a very important time," Pisano said. "We may have new guidelines for women in the next one to four years."
Computer-aided detection (CAD), in which software visually highlights potential trouble spots in a mammogram, is another enhancement researchers are investigating. One retrospective study found that CAD increased a radiologist's breast cancer detection rate when compared to a double reading by radiologists.
"CAD is not meant to replace the doctor," cautioned Dr. Stamatia Destounis, an author of the study and a radiologist at Elizabeth Wende Breast Clinic in Rochester, N.Y. "The whole point of the CAD system is to help us with some of the threshold cases. The doctor also finds cancers that CAD doesn't see, so together you get an extra 5 to 7 percent increased detection rate."
Radiation technologies are also being used to devise better treatments. Ablation therapy, for instance, relies on MRI to guide a thermal device directly to a tumor so as heat it up and obliterate it. The MRI not only guides the needle into the breast, but also shows the cancer cells being killed.
"It's an outpatient procedure done with only local anesthesia. Most women resume normal activities within the next few days. A few even went back to work the next day," said Dr. Steven Harms, professor of radiology at the University of Arkansas for Medical Sciences in Little Rock. "We see it as a replacement for surgery."
The technique is not yet widely available, and Harms emphasized the need for clinical trials. Harms is medical director of Aurora Imaging Technology, which manufactures an MRI device used for this application.
Finally, there is brachytherapy. It's an alternative to external radiation after a lumpectomy, and is becoming increasingly available in North America.
This technique, already several years old, involves delivering radiation seeds directly to the tumor via hollow plastic tubes. "We can place tiny radioactive seeds about the size of the head of a pencil inside these catheters, putting radiation on the inside out rather than the traditional outside in," said Dr. Robert R. Kuske, a radiation oncologist with Arizona Oncology Services in Scottsdale.
"Since the radiation is inside the breast, we can deliver six-and-a-half weeks' worth in just four or five days," he added. Brachytherapy, which is reserved for tumors three centimeters or less in size and that have little or no lymph node involvement, also involves fewer side effects; it spares the skin, breast, heart, lungs and ribs, and causes little scarring.
The recurrence rates are low, about 3 percent to 4 percent, but experts have data over only four years. "We're hoping that the recurrence rates will be the same as or slightly better than more convenient treatment," Kuske said. "It's safer, so that's a potential home run in the treatment of breast cancer."
For more on breast cancer treatment, visit the National Cancer Institute.