DCIS Breast Cancer

Ductal carcinoma in situ (DCIS) is the earliest stage of breast cancer, in which the milk ducts in the breast become cancerous. In situ basically means in place, hence in DCIS breast cancer the cancerous cells are confined to the milk ducts and do not spread into the fatty breast tissue or to any other part of the body like the lymph nodes. Although it is not life-threatening, it somehow increases the risks of having invasion breast cancer in women. Also called stage 0 cancer, in DCIS breast cancer, the cancer does not spread beyond the ductal system and so the cure rate for DCIS is close to 100% if diagnosed early and treated in time.

Causes
Though the actual cause is still unknown, some probable causes that can promote abnormal cell growth in the breast are given below:

• BRCA1 and BRCA2 are tumor suppressor genes that play a key role in suppressing breast cancer. Inheritance of a BRCA gene mutation can increase the risks of developing DCIS breast cancer.
• Excessive exposure to the radiations or certain chemicals can cause an acquired gene mutation which can be a probable cause of breast cancer.
• Women who started menstruating early, had late menopause or never had children are at increased risk of DCIS breast cancer. Taking combined estrogen-progestin hormone replacement therapy after menopause can also be considered as a risk factor.
• Moderate alcohol or red meat consumption, inadequate exercise or being overweight are some other probable causes.

Symptoms
Since DCIS generally has no prominent signs or symptoms, most women are unaware of having DCIS until the time of diagnosis. However, some women may have a lump developed in the breast or some fluid discharge coming out of the nipples.

Diagnosis
Mammography is most common method used to diagnose DCIS. In this, low dose amplitude X-rays are used for examining the breast tissue. Microscopic breast changes like white calcium deposits known as microcalcifications in the infected areas, can be easily detected through X-rays. Another way of diagnosing is the breast biopsy, involving three procedures:

• Core Needle Biopsy: In this the surgeon uses a hollow needle to remove tissue samples from the suspicious area, that are sent for lab analysis.
• Stereotactic Biopsy: This type of biopsy also involves removing tissue samples with a hollow needle, but with the help of stereo images i.e., mammogram images of the same infected area from different angles.
• Surgical Biopsy: Also known as wide local excision or lumpectomy, in this the surgeon may remove surgically a wider area of breast tissue for analysis.

Treatment
Depending upon the size of the tumor, grade, cell structure and aggressiveness of DCIS, patients may undergo surgery in addition to radiation therapy or hormone therapy. Some patients may opt for complete removal of the breast affected by DCIS (mastectomy), while others choose the surgical removal of DCIS and surrounding tissue (lumpectomy). Mastectomy is a breast-removing surgery which involves removal of the breast tissue, skin, areola, nipple, and possibly the underarm lymph nodes (sentinel node biopsy). Lumpectomy is a breast-conserving surgery which involves removal of only suspicious areas of the breast. After the surgery the patient has to undergo either radiation or hormone therapy to limit the chances of recurrences. In radiation therapy, patients are exposed to high-energy X-rays to destroy the remaining cancer cells, whereas in hormone therapy, a drug tamoxifen (Nolvadex) is used to block the action of estrogen, a hormone that triggers breast cancer and promotes tumor growth.

DCIS breast cancer prognosis primarily depends upon the treatment given and the patient's response to the treatment. Fortunately, the breast cancer recurrences outside the breast in patients suffering DCIS is nearly 1%, hence if diagnosed and treated early, the survival rates are almost 100%.