Women often are told it’s the earliest form of breast cancer, but it acts more like pre-cancer — a growth in the milk ducts called DCIS. Diagnosed in over 55,000 women a year, it’s vexing to treat.
A major new study shows just how vexing, uncovering vast differences around the country in how these growths are removed — suggesting some women are overtreated and others undertreated — and giving new urgency to efforts to educate patients about their choices.
This growth, named ductal carcinoma in situ, causes intense confusion.
“You hear that carcinoma word, and everybody thinks, ’Oh my God, this is exactly like the big breast cancer that the lady down the road had chemo for eight months for,”’ says Dr. Monica Morrow, director of breast surgery at Chicago’s Northwestern Memorial Hospital.
In fact, it’s very different. Removing DCIS prevents invasive breast cancer, the kind of cancer that can spread through the body and kill. Only about 2 percent of patients originally diagnosed with DCIS die of breast cancer in the next 10 years.
“Understand that your risk of dying of cancer is incredibly low, and there is no rush to be in the operating room in a couple of days,” Morrow tells the newly diagnosed.
Some call DCIS pre-cancer, a cluster of abnormal, cancer-like cells in the milk ducts. Others call it “stage zero” breast cancer, the very earliest form. Whatever the name, true DCIS is noninvasive, meaning it hasn’t penetrated into the breast tissue and can’t itself spread to other parts of the body, explains Morrow.
But it’s important to make sure the woman has pure DCIS and not a mix of that and invasive breast cancer.
Also crucial is trying to tell who has a more aggressive form of DCIS, because those women are more likely to suffer a later bout of invasive breast cancer, the life-threatening kind.
Geography plays a role
The problem: Doctors don’t yet have a good way to make that prediction, which makes selecting a treatment difficult. Do women need a mastectomy or lumpectomy? Radiation or not? Lymph node removal or not?
Such questions have arisen only relatively recently. Before 1980, doctors hardly ever diagnosed DCIS. Since then as mammogram use grew, diagnosis of DCIS skyrocketed, to 55,700 new cases last year alone.
Now University of Minnesota scientists have discovered that which treatment is selected may depend more on where the patient lives and which surgeon she chooses than on the actual characteristics of the DCIS.
The study tracked 25,000 women diagnosed with DCIS throughout the 1990s. Among the findings:
—The proportion who had a mastectomy dropped from 43 percent to 28 percent during that time. Mastectomies sometimes are required for DCIS if there is more than one growth or it’s so large that a lumpectomy makes no sense. No one knows what an optimal mastectomy rate is, although specialists believe it should be low.
—Overall about half of patients who had a lumpectomy for DCIS received radiation afterward. While radiation isn’t recommended for everyone, there was wide geographic variability: Only 39 percent of women in parts of California got radiation, compared with 74 percent in Hawaii.
—Worse, a third whose DCIS was found to be aggressive — the medical term is comedo histology — didn’t get radiation.
—Removal of lymph nodes from the armpit isn’t recommended for DCIS, yet in some regions more than 40 percent of patients underwent that extra step.
“We have to acknowledge the fact that there’s this variation and figure out why and what we should do,” says Dr. Nancy Baxter, who led the study published in last week’s Journal of the National Cancer Institute. “The lion’s share is not patient preference.”
The good news: Baxter found that while overall DCIS skyrocketed, the proportion that shows signs of being most aggressive stayed about the same.
So what’s the best treatment advice?
A consumer group, the National Center for Policy Research for Women and Families, recently held a government-funded meeting of DCIS specialists to reach a consensus on best practices, and plans to issue patient advice later this year.
There’s a lot of scientific disagreement, but specialists did stress a thorough pathologic exam to determine DCIS aggressiveness, trying to save the breast, and post-surgery therapy for the right candidates, said center director Diana Zuckerman. That might mean, for example, that a 75-year-old or a woman with some other life-threatening disease could skip radiation while an otherwise healthy 40- or 50-year-old should get it.
“You need to take the time to understand your options,” Northwestern’s Morrow stresses. “If there’s ever a disease that’s worthwhile seeking a second opinion on, it’s DCIS.”