Showing posts with label ductal carcinoma in situ. Show all posts
Showing posts with label ductal carcinoma in situ. Show all posts

Thursday, January 8, 2009

The Difference Between Ductal Carcinoma In Situ (DCIS) and Invasive Breast Cancer

Ann Romney recently reported that she was being treated for ductal carcinoma in situ (DCIS). The headlines read that she was being treated for breast cancer, but Mrs. Romney was very clear in her statement that DCIS is technically a precancer because it is not invasive.
DCIS is often referred to as an early stage of breast cancer, but there is an important distinction. DCIS differs from invasive cancer in that it stays in the breast ducts. It is the capacity to spread, or metastasize, that makes invasive breast cancer dangerous. The concern with DCIS – a noninvasive cancer — is that it can transform to become invasive breast cancer.
Scientists believe that DCIS would not always progress to breast cancer. Once detected, though, it is removed surgically to eliminate the possibility that it would become cancer because no one can predict which women would have it transform and which would not.
DCIS is a serious condition that requires treatment, but many women face greater anxiety than they should because it is referred to as an early stage of breast cancer. The implication is that it is the first of an inevitable series of stages. Instead, it is a precancerous lesion that could undergo a transformation to become invasive. The distinction is important, but it is often lost.
Depending on how extensive the DCIS is and what its characteristics are, it may be removed with a lumpectomy or a mastectomy and may require radiation. The risk of recurrence is very low.
There are sometimes stories in the news about women with DCIS choosing to have both breasts removed to prevent the possibility of getting breast cancer. Having a bilateral prophylactic mastectomy for DCIS is more than is needed, though it might be considered when a woman has additional risk factors like a faulty BRCA gene or a very strong family history of breast cancer.
Mrs. Romney’s health care providers deserve credit for being clear about what her diagnosis meant. Too many women who are diagnosed with DCIS do not realize that it has important differences from invasive breast cancer. With proper treatment and attention to lifestyle factors that reduce breast cancer risk, future problems are unlikely.

Sunday, November 16, 2008

Understanding Breast Cancer Risk

All women are at risk for breast cancer -- and most of us think our risk is higher than it actually is.

The commonly cited statistic – that women have a 1 in 8 lifetime risk of breast cancer – is a bit misleading because 1 in 8 women in the United States do not actually get breast cancer. The 1 in 8 number is an estimate of lifetime risk. A woman with average risk has a 1 in 8 chance of getting breast cancer sometime during her life if she lives to be 90. Some women are less likely to get breast cancer, and some have a greater risk. Some will not live to be 90.

A more meaningful way to look at risk is the chance of getting breast cancer during each decade of life. A woman in her twenties has a 1 in 1,837 (0.05%) risk of getting breast cancer, and her risk increases as she ages to a maximum in her seventies of 1 in 26 (3.88%). If you add up the percentages for each decade, you get 13% lifetime risk (1 in 8). During no ten-year period during her lifetime, though, does a woman face a risk of getting breast cancer as high as 1 in 8.

Of course, some women are at greater risk of developing breast cancer. And they, too, overestimate their risk for getting this disease.

Women with a faulty breast cancer gene are said to have “up to” an 85% lifetime risk of getting breast cancer, but according to the National Cancer Institute, the risk ranges from 36% to 87%. As with women who have an average risk, their chance of getting breast cancer increases as they age. (The exception to this is women with close relatives who got breast cancer when they were young.)

Others with a higher than average risk for breast cancer are women diagnosed with precancerous conditions like lobular carcinoma in situ or atypical hyperplasia. Women who have had breast cancer or ductal carcinoma in situ, a noninvasive cancer, are also at increased risk.
It should be noted that many women who are high risk will never get breast cancer. No one knows why they don’t or why some women get breast cancer even though they have no risk factors. The interplay of genetic make-up, age, reproductive history, environmental exposures, and lifestyle determines whether or not we develop breast cancer.

But those of us who are high risk can’t help feeling we’re destined to get breast cancer. Some choose overly aggressive treatment because they can’t live with the possibility that they might get this disease. They get bilateral mastectomies, reducing their risk by 90%. In some cases, this surgery is more drastic treatment than is necessary, and it does not guarantee they will never get breast cancer.

Women do it to ease their fears. Being high risk for breast cancer is more frightening than it should be because of misperceptions about the level of risk for the average woman.

Friday, October 31, 2008

Overestimating Breast Cancer Risk

Whenever I hear that a woman has a 1 in 8 risk of being diagnosed with breast cancer, I cringe. First, because this is a scary statistic. And second, because it is misleading.

It does not mean that 1 in 8 women in the United States will actually get breast cancer. It is an estimation that a woman has a 1 in 8 (12.3%) chance of getting breast cancer during her entire lifetime -- if she lives to the age of 85. Of course, some women die from other causes before they reach 85. The leading cause of death in women is heart disease and the leading cause of cancer death in women is lung cancer, not breast cancer.

The 12.3% figure comes from adding up the average risk women face during each decade of their lives. Some women face a higher or lower risk than average, but according to the American Cancer Society, a woman’s chance of being diagnosed with breast cancer is:

Age
20-29...........0.05%..........1 in 1,837
30-39...........0.43%.............1 in 234
40-49...........1.43%...............1 in 70
50-59...........2.51%...............1 in 40
60-69...........3.51%...............1 in 28
70-79............3.88%..............1 in 26
----------------------------------------------
Lifetime......12.28%.................1 in 8

The lifetime risk is roughly the sum of the risk in each decade. (The math whizzes among us may have noticed that the percentages for each decade do not add up to 12.28%, but to 11.81%. These numbers were taken directly from the American Cancer Society’s Breast Cancer Facts and Figures 2007-2008, and do not include risk to age 85.) What is clear – though a bit mysterious mathematically – is that at no time during her life does a woman face a risk of getting breast cancer as high as 1 in 8. No one should be mislead to think that if she’s sitting in a room with 8 women, one of them is destined to get breast cancer.

I am not among the mathematically inclined, but I do have to question whether it’s valid to add up the risk during different periods to get a picture of overall risk. Suppose we were trying to predict the weather instead of the likelihood of getting breast cancer. If the forecast next week was for a 10% chance of rain each day, you’d expect pleasant weather. But if you added up the risk for each day and estimated that there was a 70% chance of rain next week, you’d be sure to take your umbrella.

Carrying around an umbrella is one thing, but when women are made unduly anxious about breast cancer, they may opt for overly aggressive treatment – prophylactic mastectomy -- when they are diagnosed with precancerous conditions, ductal carcinoma in situ (DCIS), or the breast cancer gene. Hearing you’re high risk for breast cancer becomes even more frightening when you have an inaccurate perception of what average risk is.

Wednesday, October 8, 2008

Carcinoma in situ

A diagnosis of lobular carcinoma in situ (LCIS) or ductal carcinoma in situ (DCIS) is not as scary as it sounds. The Latin term "in situ" means in place. LCIS and DCIS can not spread outside the breast unless they undergo a transformation to become invasive cancer. That capacity for spreading, or metastasizing, is what makes invasive breast cancer dangerous.

The two types of carcinoma in situ are similar in that there are abnormal cells growing within the breast, but the similarities end there. LCIS develops in structures in the breast called lobules, which are the milk-producing glands, while DCIS develops in the ducts that carry milk from these glands.

LCIS serves as a warning sign that a woman is at risk for developing breast cancer, while DCIS is considered a very early stage of breast cancer. DCIS might more accurately be called a precancer, though, because it has no capacity to metastasize as invasive cancer does unless it first undergoes a change. It is thought that DCIS, if left untreated, would not become invasive in approximately half the women who have it, but its presence is taken seriously enough for it to be treated as early cancer.

Depending on how extensive the DCIS is and what its characteristics are, it may be removed surgically with a lumpectomy or a mastectomy, and it may require radiation. The risk of recurrence is very low.

The usual treatment for LCIS is not really treatment, but careful surveillance. Women get regular breast exams and a yearly mammogram. Thirty or forty years ago, LCIS was considered cancer, and women would have a mastectomy after it was diagnosed. It was later determined that LCIS was simply a warning sign that breast cancer could develop in either breast. Both breasts have to be removed for risk to be reduced, but prophylactic mastectomy for LCIS is considered "an overly aggressive approach" according to the National Cancer Institute.

Ideas about carcinoma in situ have changed over the years and are still changing. There is some uncertainty about the implications of having it for any particular woman. No one likes to be told they are high risk for breast cancer or that they have an early stage of the disease, but it is important to understand that there is a distinction between carcinoma in situ and invasive cancer so as not to take more drastic measures than necessary.

Having a bilateral prophylactic mastectomy for either LCIS or DCIS is more than is needed unless there are additional risk factors like having a faulty BRCA gene or a very strong family history of breast cancer.

So why are women diagnosed with LCIS or DCIS told that prophylactic mastectomy is a possibility? Doctors are obligated to describe all options for treating a disease. With carcinoma in situ, as with some others, it is important to understand that the most drastic treatment is not necessarily the best.