MRIs urged in breast cancer detection
MRIs urged in breast cancer detection
By Judy Peres, Tribune staff reporter. "About MRIs and breast cancer" sidebar by the Associated Press
Copyright © 2007, Chicago Tribune and The Associated Press
Published March 28, 2007
Women who are at high risk for breast cancer should be screened with MRI in addition to mammograms, according to new guidelines from the American Cancer Society.
In addition, top researchers recommended Tuesday that anyone recently diagnosed with cancer in one breast should have magnetic resonance imaging to make sure she's not harboring an invisible tumor in the other. Their study, published in the New England Journal of Medicine, found that more than 3 percent of new breast cancer patients had cancer in the other breast that standard mammograms and physical examination missed.
Together the developments represent the latest step in the evolution of medical thinking about the use of MRI -- a sophisticated and expensive tool -- to find breast tumors. But experts caution that healthy women at low or average risk should continue to rely on mammography and physical exams to detect signs of cancer.
Widespread use of MRI, they note, could detect non-threatening cancers that don't need to be treated and therefore might do more harm than good.
"Finding more cancers is not necessarily a good thing," said Dr. Steven Woloshin of Dartmouth Medical School. "The key is whether these 'missed cancers' are ones that were destined to cause problems, and whether earlier detection and treatment has a net benefit. These issues can only be resolved with a randomized trial."
Even for women diagnosed with invasive breast cancer on the basis of conventional tests, MRI can be a double-edged sword.
Findings of additional tumor sites can affect the patient's emotional state and may lead to unnecessary mastectomies, said Dr. Nora Hansen, director of the Lynn Sage Comprehensive Breast Center at Northwestern Memorial Hospital.
"Patients freak out," she said. "They have this knee-jerk reaction -- 'I just want everything taken out.'
"
The cancer society says women at high risk will benefit from the addition of MRI to their regular screening tests because MRI is more sensitive and finds smaller tumors compared to mammography.
The new guidelines recommend that all women whose lifetime risk of breast cancer is around 20 percent or higher get an annual MRI. A 60-year-old white woman with no children and two close relatives with breast cancer has a 23 percent chance of being diagnosed before her 90th birthday. The average American woman's lifetime risk is 13 percent.
Women who automatically fit into the high-risk category include those with a genetic mutation that predisposes to breast cancer, such as BRCA carriers.
The society said evidence was insufficient to recommend for or against MRI screening in women with a personal history of breast cancer or precancerous conditions. But its recommendations were written before the latest study was completed.
That study looked at 969 women recently diagnosed with cancer in one breast but not the other. All were given MRIs of the second breast, which found possible cancer in 121 women. Biopsies confirmed invasive cancer in 18 of them. Twelve had ductal carcinoma in situ, which sometimes but not always progresses to invasive cancer.
"This study is pretty definitive evidence that the opposite breast needs to be evaluated with MRI," said study author Dr. Etta Pisano of the University of North Carolina.
Up to 10 percent of women treated for cancer in one breast are later diagnosed with cancer in the other, Pisano noted. That could mean undergoing two rounds of cancer treatment -- surgery and possibly radiation and chemotherapy -- when one round would suffice for two cancers detected at the same time.
Hansen of Northwestern Memorial said she discusses the pros and cons of MRI with each new breast cancer patient.
"If you have an MRI you may have to have additional tests -- such as ultrasound and biopsies -- that could delay your surgery and may not be necessary," she said. "We don't know if treating [the tiny cancers detected by MRI] will make a difference in your outcome. But once we find something, we can't ignore it."
Of particular concern are noninvasive cancers, such as ductal carcinoma in situ. There is no evidence that treating DCIS when it's detected is better than waiting to treat it until it progresses. But almost no one is comfortable leaving it in place and taking that chance.
Hansen is also concerned about the cost of screening all new breast cancer patients with MRI, which can run to "several thousand dollars" and often is not covered by insurance.
"Over 200,000 new breast cancer patients are diagnosed each year," Hansen noted. "To do a $3,000 test on each one to find 3 percent with [a tumor in the opposite breast] seems like a big expense -- not for those with the cancer, but in terms of public health policy."
About MRIs and breast cancer
The American Cancer Society is recommending MRIs in addition to mammograms for certain women considered to be at unusually high risk for breast cancer. Here are more details:
Q. Who should get an MRI?
A. Those with a mutation in the BRCA1 or BRCA2 genes; those who were treated for Hodgkin's disease; those with a strong family history of the disease, such as women with two or more close relatives who had breast or ovarian cancer or who have a close relative who developed breast cancer before age 50. Experts say about 1 in 50 adult U.S. women fall into this category.
Also, a new study suggests MRI is useful for women diagnosed with cancer in one breast.
Q. Why is an MRI necessary?
A. MRIs are better at showing increased or abnormal blood flow in the breast, a sign of early cancers not visible on a mammogram. They also are better than mammograms at detecting cancer in women with dense, non-fatty breasts.
Q. Why do I still need to get a mammogram, then?
A. Mammography is considered a very good diagnostic technique, and it can show things MRIs miss, like calcium deposits, which are usually benign but which can occur in patterns that indicate breast cancer.
Q. What are the downsides of MRI?
They make mistakes -- one estimate is 5 percent to 25 percent of MRI positive tests are wrong. That can lead to unnecessary biopsies and mental anguish. They are expensive, and not all insurers will pay.
Q. How do I choose an MRI testing facility?
A. Some medical facilities that offer MRI lack the expertise and equipment to do MRI-guided biopsies. The cancer society says breast MRIs should be done at places that do biopsies as well.
-- Associated Press
----------
jperes@tribune.com
By Judy Peres, Tribune staff reporter. "About MRIs and breast cancer" sidebar by the Associated Press
Copyright © 2007, Chicago Tribune and The Associated Press
Published March 28, 2007
Women who are at high risk for breast cancer should be screened with MRI in addition to mammograms, according to new guidelines from the American Cancer Society.
In addition, top researchers recommended Tuesday that anyone recently diagnosed with cancer in one breast should have magnetic resonance imaging to make sure she's not harboring an invisible tumor in the other. Their study, published in the New England Journal of Medicine, found that more than 3 percent of new breast cancer patients had cancer in the other breast that standard mammograms and physical examination missed.
Together the developments represent the latest step in the evolution of medical thinking about the use of MRI -- a sophisticated and expensive tool -- to find breast tumors. But experts caution that healthy women at low or average risk should continue to rely on mammography and physical exams to detect signs of cancer.
Widespread use of MRI, they note, could detect non-threatening cancers that don't need to be treated and therefore might do more harm than good.
"Finding more cancers is not necessarily a good thing," said Dr. Steven Woloshin of Dartmouth Medical School. "The key is whether these 'missed cancers' are ones that were destined to cause problems, and whether earlier detection and treatment has a net benefit. These issues can only be resolved with a randomized trial."
Even for women diagnosed with invasive breast cancer on the basis of conventional tests, MRI can be a double-edged sword.
Findings of additional tumor sites can affect the patient's emotional state and may lead to unnecessary mastectomies, said Dr. Nora Hansen, director of the Lynn Sage Comprehensive Breast Center at Northwestern Memorial Hospital.
"Patients freak out," she said. "They have this knee-jerk reaction -- 'I just want everything taken out.'
"
The cancer society says women at high risk will benefit from the addition of MRI to their regular screening tests because MRI is more sensitive and finds smaller tumors compared to mammography.
The new guidelines recommend that all women whose lifetime risk of breast cancer is around 20 percent or higher get an annual MRI. A 60-year-old white woman with no children and two close relatives with breast cancer has a 23 percent chance of being diagnosed before her 90th birthday. The average American woman's lifetime risk is 13 percent.
Women who automatically fit into the high-risk category include those with a genetic mutation that predisposes to breast cancer, such as BRCA carriers.
The society said evidence was insufficient to recommend for or against MRI screening in women with a personal history of breast cancer or precancerous conditions. But its recommendations were written before the latest study was completed.
That study looked at 969 women recently diagnosed with cancer in one breast but not the other. All were given MRIs of the second breast, which found possible cancer in 121 women. Biopsies confirmed invasive cancer in 18 of them. Twelve had ductal carcinoma in situ, which sometimes but not always progresses to invasive cancer.
"This study is pretty definitive evidence that the opposite breast needs to be evaluated with MRI," said study author Dr. Etta Pisano of the University of North Carolina.
Up to 10 percent of women treated for cancer in one breast are later diagnosed with cancer in the other, Pisano noted. That could mean undergoing two rounds of cancer treatment -- surgery and possibly radiation and chemotherapy -- when one round would suffice for two cancers detected at the same time.
Hansen of Northwestern Memorial said she discusses the pros and cons of MRI with each new breast cancer patient.
"If you have an MRI you may have to have additional tests -- such as ultrasound and biopsies -- that could delay your surgery and may not be necessary," she said. "We don't know if treating [the tiny cancers detected by MRI] will make a difference in your outcome. But once we find something, we can't ignore it."
Of particular concern are noninvasive cancers, such as ductal carcinoma in situ. There is no evidence that treating DCIS when it's detected is better than waiting to treat it until it progresses. But almost no one is comfortable leaving it in place and taking that chance.
Hansen is also concerned about the cost of screening all new breast cancer patients with MRI, which can run to "several thousand dollars" and often is not covered by insurance.
"Over 200,000 new breast cancer patients are diagnosed each year," Hansen noted. "To do a $3,000 test on each one to find 3 percent with [a tumor in the opposite breast] seems like a big expense -- not for those with the cancer, but in terms of public health policy."
About MRIs and breast cancer
The American Cancer Society is recommending MRIs in addition to mammograms for certain women considered to be at unusually high risk for breast cancer. Here are more details:
Q. Who should get an MRI?
A. Those with a mutation in the BRCA1 or BRCA2 genes; those who were treated for Hodgkin's disease; those with a strong family history of the disease, such as women with two or more close relatives who had breast or ovarian cancer or who have a close relative who developed breast cancer before age 50. Experts say about 1 in 50 adult U.S. women fall into this category.
Also, a new study suggests MRI is useful for women diagnosed with cancer in one breast.
Q. Why is an MRI necessary?
A. MRIs are better at showing increased or abnormal blood flow in the breast, a sign of early cancers not visible on a mammogram. They also are better than mammograms at detecting cancer in women with dense, non-fatty breasts.
Q. Why do I still need to get a mammogram, then?
A. Mammography is considered a very good diagnostic technique, and it can show things MRIs miss, like calcium deposits, which are usually benign but which can occur in patterns that indicate breast cancer.
Q. What are the downsides of MRI?
They make mistakes -- one estimate is 5 percent to 25 percent of MRI positive tests are wrong. That can lead to unnecessary biopsies and mental anguish. They are expensive, and not all insurers will pay.
Q. How do I choose an MRI testing facility?
A. Some medical facilities that offer MRI lack the expertise and equipment to do MRI-guided biopsies. The cancer society says breast MRIs should be done at places that do biopsies as well.
-- Associated Press
----------
jperes@tribune.com
posted by Carlos T Mock @ 6:21 AM
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