WASHINGTON — A new Canadian study has reignited the debate about treating a condition sometimes known as “Stage 0” breast cancer.
It’s called ductal carcinoma in situ, or DCIS, and it occurs when cancerous cells turn up in milk ducts in the breast. Two-thirds of the time, those cells don’t move, but in some cases, they have the potential to spread and turn deadly.
Currently, almost all women who get DCIS undergo treatment, usually in the form of a lumpectomy and radiation or a mastectomy, because it is impossible to predict at the time of diagnosis whose cancer cells will break through protective membranes.
That led the Canadians, who crunched U.S. government data on more than 100,000 cases, to suggest some of these women were over-treated. Their report, published in the journal JAMA Oncology, says radiation after surgery did not increase their chances of survival.
A local breast cancer expert challenges that assertion on scientific and personal terms.
“There are two ways of looking at it,” says Dr. Rachel Brem, director of the GW Comprehensive Breast Center and a breast cancer survivor.
She says it’s true that two-thirds of DCIS patients are over-treated, but she adds the only way to help the women who really need it is to treat them all.
“The whole controversy of over-diagnoses is that we treat all women with DCIS because we have the opportunity to save the life of a third of them,” Brem says, adding that it’s impossible to know who will benefit.
She says modern medicine has the opportunity here “to life-save, as imperfect as it may be.”
Research is underway to better understand which women with DCIS have cancer cells that are biologically predisposed to spread, and advances in genetics are giving the effort a boost.
Brem says the stakes are especially for younger women and African-American women. The Canadian study put the overall mortality rate 20 years after diagnosis at 3 percent for women whose cancer was confined to a milk duct. It was twice as high for women under 35 and black women.
