Breast Cancer Study Finds All Lumps Aren't Created Equal

July 21, 2005 — -- When Amanda Radcliffe and Sharon Seal each found a lump in their breasts, they both spent anxious weekends wondering if they would be joining the nearly 200,000 other women in America who develop breast cancer every year.

"There's just no words to describe the feeling when you find a lump," Radcliffe recalled."It was sheer terror."

Both women were relieved to learn the lump was not cancerous. But a new study published today in the New England Journal of Medicine shows that even a benign growth may be cause for worry.

Dr. Neil Friedman, the cancer expert at Mercy Hospital in Baltimore who treated Seal, said findings confirm something that has long seemed apparent to doctors: Women who have had breast lumps in the past are at a greater risk for developing cancer.

Researchers have learned not all benign tumors are created equal. Some are merely an overgrowth of normal cells, called a proliferative lesion. But sometimes these cells take on strange shapes. This condition, called atypia, is often a precursor to cancer.

The new study found that women whose benign lump showed signs of proliferation and atypia were about 400 percent more likely to develop breast cancer in their lifetimes.

While these numbers sound scary, Dr. Marisa Weiss, who founded breastcancer.org, cautions against overreacting. For instance, Weiss explained that if you had a 1 percent chance of developing breast cancer and that chance rose by 400 percent, you would now only have a 4 percent chance of getting the disease.

So when studies say that having a benign lump increases your risk by 50 percent, Weiss says women have to think through the numbers carefully. "Yes, your risk increases by 50 percent. But that doesn't mean that your risk [of getting cancer] is 50 percent."

About 20 percent of all American women will have a breast biopsy at some point in their lives, but for most of them, the results will be good news. Eighty percent of women with a benign lump will never develop cancer. But when women who are older than 50, who are overweight or who have a family history of the disease find a benign lump, the odds stack in favor of the cancer.