Ductal carcinoma in situ (DCIS), also known as intraductal carcinoma, is a pre-cancerous or non-invasive cancerous lesion of the breast. DCIS is classified as Stage 0. It rarely produces symptoms or breast lumps, and it is usually detected through screening mammography. DCIS has been classified according to architectural pattern (solid, cribriform, papillary, and micropapillary), tumor grade (high, intermediate, and low grade), and the presence or absence of comedo histology. DCIS can be detected on mammograms by examining tiny specks of calcium known as microcalcifications. Since suspicious groups of microcalcifications can appear even in the absence of DCIS, a biopsy may be necessary for diagnosis.
DCIS doesn't cause any signs or symptoms in most cases. However, DCIS can sometimes cause signs and symptoms, such as: a breast lump and a bloody nipple discharge DCIS is usually found on a mammogram and appears as small clusters of calcifications that have irregular shapes and sizes. Surgical remova and therapeutic usage of tamoxifen, is the recommended treatment for DCIS. Surgery may be lumpectomy or a mastectomy (complete or partial removal of the affected breast). Tamoxifen may be used as hormonal therapy if the cells show estrogen receptor positivity. Radiation therapy and mastectomy are known to be the best treatment methods. Use of radiation therapy after lumpectomy provides equivalent survival rates to mastectomy, although there is a slightly higher risk of recurrent disease in the same breast in the form of further DCIS or invasive breast cancer. Mastectomy; decreases the rate of the DCIS or invasive cancer occuring in the same location.
For women under the age of 50, breast cancer rates have remained stable since the middle to late 1980s. Rates of DCIS have stabilized since 2000. Whereas a decline in invasive breast cancer rates was evident as early as 1999, rates decreased dramatically in women aged 50 years or older between 2001 and 2004. It is notable, however, that the annual percentage change from 2005 to 2009 increased in women aged 65-74 years by 2.7% during this period, rates that parallel 2001 incidence figures for this age group. The incidence rate of breast cancer increases with age, from 1.5 cases per 100,000 in women 20-24 years of age to a peak of 421.3 cases per 100,000 in women 75-79 years of age; 95% of new cases occur in women aged 40 years or older.