Ductal Cancer in Situ (DCIS): Difficult Choices for Treatment

Feb 5, 2012
C. Marie

Confined Ductal Precancerous Cells in the Breast - wikimediacommonns

DCIS means precancerous cells are in the milk duct of the breast. The decision to perform lumpectomy or mastectomy is complex for both doctor and patient.

Almost all breast cancers start in the milk ducts or the lobules, which manufacture milk. When a cluster of abnormal cells is discovered in one or more of the ducts, the condition is called ductal cancer in situ, or DCIS. According to Gayle A. Sulik, author of Pink Ribbon Blues, DCIS is very common:

Is DCIS Breast Cancer?

“DCIS, representing 85 percent of in situ diagnosis, is at the center of an ongoing debate.” Sulik, (2011 p.166)

According to Sulik, some physicians are of the opinion that DCIS should not even be labeled “cancer” at all. The cells are abnormal, and may or may not be a precursor to cancer.

She explains that the scale physicians use to rate the level of danger of a breast cancer diagnosis is Stage 1 to Stage 4, and many doctors believe that DCIS is stage “zero.” Sulik explains that DCIS is treated far too aggressively, and that many cancer "survivors" never had the disease.

“Yet DCIS is diagnosed more frequently and treated more aggressively in the United States than anywhere else in the world.” Sulik, (2011, p.184)

One in four cases of DCIS is treated by total mastectomy, according to Sulik. But in her book she states:

“Seventy percent of DCIS lesions remain harmless for a lifetime and the long-term survival rate is nearly 100 percent, regardless of treatment.” Sulik, (2011 p.184)

A Closer Look at DCIS

Dr. Susan Love, clinical professor of surgery at UCLA and author of the book, Dr. Susan Love’s Breast Book, states:

“DCIS is more common than LCIS (lobular carcinoma in situ) and it is more likely to grow into invasive cancer.” Love (2011 p. 370)

DCIS is not a lump, but a thickening in breast tissue, because it is inside a duct. However, it is easily detected by mammography. According to Dr. Love,

“A full 20% of malignancies detected by screening mammography are DCIS.” Love (2011 p. 370.)

Love agrees with Sulik that DCIS - which she refers to as “atypical hyperplasia,”(p. 371) and “precancer” (p. 366) - is very common. She explains:

“Autopsies done on women who died from all kinds of other causes show that between 6 and 16 percent had DCIS.” (Love 2011 p. 370)

Difficulty Determining Treatment for DCIS

The choice of treatment for DCIS is difficult for both doctor and patient. Dr. Love reports that mastectomy used to be the standard treatment for DCIS. However, she notes that, because total mastectomy was the norm for treatment of DCIS, there is no data available to ascertain how many women would have lived a normal life span with untreated DCIS.

Dr. Love observes that while in the majority of women, DCIS does not become invasive cancer, there exists no present method of accurately predicting which cases of women with DCIS will progress to invasive cancer.

Therefore, numerous factors must be considered when choosing between lumpectomy, lumpectomy followed by radiation, total mastectomy and bilateral total mastectomy.

What is Lumpectomy and Why is it Followed by Radiation?

Dr. Love explains that when abnormal cells are removed, DCIS cannot progress to invasive cancer.

Lumpectomy is the excision of a wide area around the abnormal cells. The cells are carefully studied for the following characteristics:

If a clearly defined “rim” or a wide (1 cm) circle of normal cells surrounds the abnormal cells, this is the perfect scenario for a simple lumpectomy, because it confirms that the atypical cells are enclosed in clearly defined and well circumscribed area.
Without this rim, lumpectomies are often followed by recurrence, which actually means that not all abnormal cells were excised in the first surgery. This is why radiation often follows lumpectomy.
Radiation therapy following lumpectomy has been shown to reduce recurrence by 50 – 60%. Even in the case of a confined area of abnormal cells, radiation therapy commonly follows lumpectomy.

The Choice of Mastectomy

There are important considerations in the decision to have a mastectomy to remove DCIS. To begin, mastectomy is the “ultimate wide excision” Love (2011 p.375). The decision to perform mastectomy is largely based on the size of the lesion, which can be very large, because DCIS can fill the whole ductal system, which comprises one-third of the breast. Dr. Love writes:

“…if the extent of the lesion is too large to allow for a cosmetic excision then a mastectomy is indicated.” (Love 2011 pp.372 – 373).

In other words, if the removal of a lump involves such a large amount of tissue that the breast is seriously deformed by the procedure, it is wiser to have a total mastectomy. If deformity will be the end result, total mastectomy will at least provide improved protection from recurrence.

Other reasons for choosing total mastectomy:

Milk ducts are completely separated in the breast. If DCIS is isolated to one duct, lumpectomy may be sufficient treatment. However, if DCIS is spread throughout ducts in the breast (multi-centric), it may indicate the need for mastectomy of both breasts.
Large lesions are easily detected by mammograms. But Dr. Love warns that smaller, undetected pockets may have infiltrated the breast with DCIS. These invisible but potentially insidious pockets of atypical cells may become invasive cancer.
Because DCIS can easily spread throughout the breast, some women with DCIS require total mastectomy, while other women with more serious tumors that are strictly isolated can be treated with lumpectomy.

The ultimate decision to treat DCIS with total mastectomy is an agonizing one for the physician and a life and death decision for the patient. According to Dr. Love, the goal of treatment of DCIS is prevention of breast cancer:

“Generally we only do a mastectomy if the DCIS is so extensive that it is the only choice or if the patient strongly wants it.” Love (2011 p.375).

Other Considerations

Genetic studies are highly recommended by Dr. Love, because several genetic markers have been discovered that can predict the likelihood of DCIS recurrence from 4% to 19%; a factor to be weighed carefully in the decision for treatment.
One of the biomarkers that can predict whether or not a cancer will be sensitive to hormone treatment is the existence of estrogen receptors. Ironically, younger women often have negative estrogen receptors, which is associated with rapidly growing cancer.

The Mastectomy Debate Continues

The Preventive Mastectomy Center in New York promotes preventive mastectomy for women in the following categories:

Women with a family history of breast cancer.
Women with previous cancer in one breast.
Women with mutations in the genes called BRCA1 or BRCA2, which are associated with breast cancer risk.

However a report delivered at the American Society of Clinical Oncology (ASCO) meeting in Chicago, 2011, indicated that "preventive" double mastectomy is being overused. The ASCO argues that the rate of cancer spreading to a second breast has significantly declined, while surgical treatment by double mastectomy is becoming more common.

Treatment of DCIS is Not an Easy Decision

Although breast cancer advocates feel that treatment of DCIS may be too aggressive, the choice of lumpectomy vs. total mastectomy is not a simple one. Together, the physician and a patient who is presented with the most information available from mammography, biopsy and genetic studies must decide the course of treatment for DCIS.