Columnar Cells

• Columnar cells, or columnar epithelial cells, are column-shaped cells in the epithelial layer of the skin, according to a University of the Western Cape website on epithelial tissue. Columnar cells are found in the stomach and intestine linings, the duodenum and in the breast---including ducts and lobules of glandular breast tissue.
  
  

Definition

• Columnar cell hyperplasia that occurs in breasts and glandular breast tissue is a condition characterized by lesions in the cells that line the duct and lobular units, according to the Stanford School of Medicine. Growth and placement of these columnar cell lesions vary; cells may form within the ducts in small clumps, tufts and micro-papillations.
  
  

Significance

• The presence of columnar cell hyperplasia in breasts, particularly in the ducts and lobules, indicates an increased risk for breast cancer, according to a July 29, 2009 article in Breast Cancer Research, written by Stuart J. Schnitt in conjunction with the Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Massachusetts.
  
  

Breast Cancer

• Breast lesions attributable to columnar cell hyperplasia, particularly those occurring with atypical hyperplasia, may be precursors to a type of breast cancer known as ductal carcinoma in situ (DCIS).
  
  

Atypical Hyperplasia

• Atypical columnar cell hyperplasia is characterized by the presence of cellular layers that are more than the usual one or two cell layers deep, according to the Breast Cancer Research article.