Treatments for women with an early form of breast cancer vary widely depending on where they live, which suggests doctors and patients are uncertain about the best treatment, researchers said Wednesday.
As wider screening leads to more women being diagnosed with ductal carcinoma in situ, or DCIS, it is becoming more urgent to develop consistent treatment guidelines, the researchers said.
“There is a fair amount of confusion out there,” Dr. Nancy Baxter of the University of Minnesota, who led the study published in this week’s Journal of the National Cancer Institute, said in a telephone interview.
Until clearer guidelines are developed, she said, “It is probably a good idea for women to get a second opinion.”
About 50,000 U.S women are diagnosed with DCIS each year. It looks like cancer, but the tumor cells have not spread from the breast ducts.
DCIS itself is rarely deadly, killing just about 2 percent of patients, but it can turn into a more dangerous invasive cancer if left alone or if it returns.
“The key point about DCIS is that it lacks the ability to spread to other parts of the body. Therefore, no matter what treatment a woman chooses, her risk of dying of breast cancer is extremely low,” Dr. Monica Morrow, director of breast surgery at Northwestern Memorial Hospital in Chicago, said in a statement.
Baxter studied the records of more than 25,000 women diagnosed with DCIS between 1992 to 1999.
As expected due to a rise in mammogram screenings, many more cases were diagnosed by 1999. While more than 97 percent of patients had some kind of surgery, the number who had mastectomies — removal of the breast — fell from 42 percent in 1992 to 28 percent in 1999.
But the treatment varies greatly by region.
More mastectomies in Utah
For example, 74 percent of women in Connecticut got breast-conserving surgery for DCIS — meaning they did not have full mastectomies. But only 55 percent of patients in Utah did.
“We can’t say from this that you are getting bad care in Utah and good care in Connecticut,” Baxter cautioned in a telephone interview.
“It may be that women in Utah are requesting mastectomy more because they live a long way from a radiation center. We don’t know what led to those figures.”
Experts strongly recommend that women get radiation therapy after having DCIS removed, yet Baxter found regional variations here, too. For example, just 39 percent of DCIS patients in San Francisco got radiation, compared to 74 percent in Hawaii.
“DCIS can come back,” Baxter said. “It has a very high rate of recurrence if you just remove the breast and don’t radiate people. And about half the time it comes back as invasive cancer — that is cancer cancer.”
She said there may be medically legitimate reasons for the variations, but treatment guidelines could help limit any unwarranted regional differences. “What we need to start doing is to start, as a group, coming up with some sort of recommendations in terms of treatment.”
If doctors cannot agree, she added, then research needs to be done to find out what the most effective treatments are and for who.