Ductal Breast Cancer in Situ (DCIS)

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Ductal Carcinoma in Situ, also known as Intraductal Carcinoma, is a type of noninvasive cancer that starts in the cells of the ducts of the breasts and remains contained within the ducts. 'In situ' is a Latin word meaning 'in place'. It is also referred to as 'TIS', which means 'tumor in situ' or 'in the same place'. Although the cells are cancerous, it is sometimes referred to as a precancerous condition since it is non-invasive.

DCIS is also known as Stage 0 of breast cancer. It is usually diagnosed during a mammogram done as part of breast cancer screening or to investigate a breast lump.

Ductal breast cancer is more common than lobular breast cancer. Between 85% and 90% of all breast cancers are ductal.

Because the cancer cells does not break through the wall of the duct in DCIS, the cancer cells have no access to the blood stream or the lymphatic circulation, and have no ability to spread to other parts of the body. As a result, DCIS is completely curable. It is very uncommon for death to occur due to DCIS.

But once the cells break through the duct wall, it becomes Invasive Ductal Cancer (IDC) and can spread rapidly. So, DCIS needs to be treated as early as possible.

Treatment may include breast-conserving surguries like Lumpectomy. Or the breast may need to be removed completely by Mastectomy. Radiation may also be planned in some cases of DCIS. Surgery and radiotherapy may sometimes be offered as a combined treatment module. Chemotherapy is usually not required to treat DCIS.

Ductal Breast Cancer in situ and Invasive Ductal cancer

Progress of Normal Breast Duct to DCIS and Invasive Ductal Cancer

Risk factors: Factors that may increase risks of DCIS are:

  • Increasing age
  • Personal history of benign breast disease, such as Fibrocystic breasts or dense breasts. Dense breasts have more glandular and connective tissue with very little fatty tissue.
  • Family history of breast cancer
  • Never having been pregnant
  • Having the first baby after age 30
  • Having the first period before age 12
  • Beginning menopause after age 55
  • Women who have had more children have a lower risk of DCIS than women who have had less children. Women who have had no children have an even higher risk of getting breast cancer.
  • Genetic mutations that increase the risk of breast cancer, such as those in the breast cancer genes BRCA1 and BRCA2
  • There is no association between present or past use of oral contraceptive and DCIS incidence.
  • Some studies have suggested an increased risk of DCIS in women who are on Hormone replacement therapy (HRT) for more than 5 years compared with women who have never used HRT. Most studies agree that the risk may be high while a woman is on HRT but it decreases once HRT is stopped. Other studies however have found no such increased risk.
  • Obesity, especially in women with large breasts may increase the risks of DCIS.
  • Lifestyle factors like drinking and smoking may also slightly increase the risks of getting breast cancer.

    Read More :

  • Symptoms and Grades of DCIS

  • Diagnosis of DCIS