Ductal Carcinoma In Situ (DCIS)

by PJ Hamel Patient Expert

Expert Patient PJ Hamel takes you through the basics of Ductal Carcinoma In Situ, from what DCIS is to what treatment to expect.

Q. I've just been diagnosed with breast cancer. The doctor tells me it's DCIS. What does that mean?

A. Congratulations! Seems strange to say that word in connection with cancer, but you've been diagnosed with a type of breast cancer that latest statistics show is 98% to 99% curable. (And sadly, "cure" isn't a word that's heard in connection with all breast cancers.) So take a deep breath, validate your fear-EVERY woman, no matter the diagnosis, suffers through that "kick in the gut" feeling that you're going to die-and prepare for some pretty straightforward treatment.

DCIS-ductal carcinoma in situ, also called intraductal carcinoma-refers to breast cancer that's in the breast's milk ducts, the tiny tubes that bring milk from where it's manufactured (in the lobules) to your nipple. Carcinoma (cancer) in situ (confined to site of origin) means that the cancer has remained confined to the ducts, and hasn't broken through the walls of those ducts to move into the surrounding breast tissue. About 20% of all newly diagnosed breast cancers are DCIS; and about 85% of all non-invasive cancers are DCIS (non-invasive cancers are basically not life-threatening). Technically DCIS is not cancer, but a "pre-cancerous" condition because it has not yet developed the ability to invade tissue which is a hallmark of cancer.

DCIS is diagnosed much more commonly now than it was in the past, simply because more women are getting mammograms more regularly. Researchers have discovered that many, many women with DCIS live with it for many years, without treatment, because they didn't know they had it. In fact, most in the health community are now referring to DCIS as a pre-cancerous condition, rather than fully developed cancer. However, DCIS does make you more likely to develop breast cancer, at some point in your life, than a woman without DCIS; thus it's important to get it treated. The risk of developing breast cancer is roughly 14% over 6 years from diagnosis.

Q. So, what can I expect, treatment-wise?

A. EVERY CASE IS DIFFERENT. That's the one thing you can count on with breast cancer: YOUR treatment won't be exactly the same as anyone else's. But in general, here's what to expect. You'll probably have a lumpectomy: the surgeon will remove the cancerous ducts, along with some healthy tissue around them, just to make sure it's all gone. For some women, a mastectomy may be needed, i.e. if a lumpectomy is not technically feasible or if there is concern about multi-centric disease (more than one area of the breast involved with DCIS) your surgeon might recommend mastectomy.

Then, depending on how large the cancerous area was (among other factors determined by the pathologist, who'll examine the cancer cells removed), you will likely have radiation therapy if you had a lumpectomy, to ensure that even a single cell won't survive. (This radiation affects all cells, but healthy cells "shake it off," while cancer cells, which are so busy reproducing that they're vulnerable to injury, are killed by radiation.) Finally, if the pathologist determines that your cancer is estrogen-receptive (i.e., it needs estrogen to grow), you'll probably take tamoxifen, a drug that stops cancer cells from growing by preventing them from absorbing the estrogen they need. About 50% of DCIS is estrogen-receptive.

This tamoxifen will decrease your chance of getting breast cancer over the next 6 years from about 14% to 8%.

Q. How difficult is all of this? Will I feel sick, or miss work, or...?

A. A lumpectomy is generally outpatient surgery; you'll miss a day or two or three of work, depending on your response to surgery. But you'll probably experience only minimal pain. Sometimes, in order to get "clean margins" (healthy tissue around the cancer site), it's necessary for the surgeon to operate again. Generally, these surgeries are a couple of weeks apart, and you'll feel fine and be able to work in between. But don't worry: the majority of women with DCIS need only one surgery.

If it's determined you need radiation, it'll probably take 5 to 6 weeks of treatment every day. Again, most women work right through this, and feel very little pain beyond a sunburn-type soreness. Fatigue during radiation is a more common complaint; some women feel a bit peaked, while others feel tremendously exhausted. Those at the exhausted end of the scale may find themselves missing work, and having to put their lives on hold for awhile. Finally, if you take tamoxifen, expect few side effects other than a possible propensity to gain weight. Some women find themselves prone to depression while on tamoxifen, also; if this happens to you, don't suffer in silence! Tell your doctor, so that he or she can help you deal with it.

PJ Hamel
Meet Our Writer
PJ Hamel

PJ Hamel is senior digital content editor and food writer at King Arthur Flour, and a James Beard award-winning author. A 16-year breast cancer survivor, her passion is helping women through this devastating disease. She manages a large and active online survivor support network based at her local hospital and shares her wisdom and experience with the greater community via HealthCentral.com.