Confusion About Lobular Carcinoma In Situ?

Almost every day, someone comes to this blog because they have done a Google search on the terms “LCIS” and “prophylactic mastectomy.” My breast surgeon was surprised that women needed to look this up.

Ideas have changed in the 20 years since she gave me the diagnosis of lobular carcinoma in situ (LCIS) and advised me to have regular check-ups. She added that I would hear about another way to treat LCIS, but left no doubt that her recommendation was careful follow-up. She was firm enough that when I learned the alternative was double mastectomy, I gave it less consideration than I might otherwise have.

At the time, the medical community was evenly divided on whether to recommend careful follow-up for women with LCIS or a bilateral prophylactic mastectomy. (A single mastectomy is not an option because LCIS indicates a risk for breast cancer in both breasts.) These days it would be unusual for doctors to suggest a double mastectomy, but something else may be recommended. Tamoxifen is sometimes used for prevention in women who are high risk for breast cancer.

So why, then, are people Googling “LCIS” and “prophylactic mastectomy?”

I suspect women are told there are options without being told as clearly as I was that one of the choices is by far the most reasonable. When we hear there are various ways to treat a disease, we might assume the most drastic must be the best. In this case it is not.

LCIS is not cancer, and it is not even considered a true precancer because if invasive cancer develops, it does not necessarily arise from the LCIS cells. LCIS is a warning sign that a woman is at risk for breast cancer. It sounds scarier than it is because it is called a carcinoma, or cancer. It got that label when it was first identified years ago under a microscope because the LCIS cells looked like cancer cells. The fact that there were important differences in their biological activity was learned later on.

The danger with invasive cancer is that it can spread outside the breast to other organs. LCIS does not have that capacity and remains in the breast. The phrase “in situ” is Latin for in place – and that is where LCIS stays.

There are some exceptions to favoring careful surveillance for women diagnosed with LCIS. Those who have a strong family history of breast cancer, those who have a defective form of the breast cancer gene, and those who have a type of LCIS called pleomorphic LCIS might take this warning more seriously and act more aggressively.

When the choice is not clear, however, it is wise to go for a second opinion. The best place would be one of the National Cancer Institute approved cancer centers. If there is not one nearby, look for a breast specialist by checking with a large hospital in your area. Friends, family, or your internist or gynecologist may be able to recommend a breast surgeon.

It might also be advisable to get a second opinion for the pathology report on tissue removed during biopsy. My doctor does this because there are sometimes difficulties identifying LCIS on pathology slides.

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.