Breast Calcifications Scrutinized

"DCIS in a sense is an epidemic," says Dr. Eric Winer, director of the Breast Oncology Center at Dana-Farber Cancer Institute in Boston. "It has increased in incidence clearly because of screening mammography."

The proliferation of mammography screening since the 1980s means that tiny calcifications -- microcalcifications -- that could not be felt in self-exams or at the doctor's office are popping up on film and, now, even clearer digital images, leading to follow-up mammograms, other imaging and biopsies. Macrocalcifications, which show up as larger bodies on imaging screens, are almost always noncancerous.

Still, the ability to see the microcalcifications through improved imaging is changing the face of breast cancer diagnosis.

According to a state report, the percentage of newly diagnosed cancer cases that were the noninvasive, in-situ type jumped from less than 1 percent before widespread screening to about 24 percent of all breast cancer diagnoses in 2000, the last year for which the state Department of Public Health has in-situ statistics.

For most doctors, this is good news.

"The earlier you find it, the better off you are," says Marasco, the West Yarmouth doctor who diagnosed Betty Anne Bevis' breast cancer. "The bigger the tumor grows, the more chance it has to invade and spread to other tissues and organs in the body."

The proof of this thinking is in breast cancer morbidity rates, which have been steadily declining since widespread screening started in the 1980s, he says. "The sooner you find a problem and treat it, the better."

The breast cancer death rate has been dropping more than 2 percent per year since 1990, which the American Cancer Society attributes to a combination of screening and better treatment.

That good news has brought other concerns.