Columnar cell change (CCC) is a common finding encountered in breast pathology reports, representing a benign alteration in the tissue’s microscopic structure. This diagnosis describes a condition where the normal cells lining the small ducts and lobules of the breast have changed their shape. While the term may sound concerning, CCC itself is considered non-cancerous and is often found incidentally during a biopsy performed for other reasons. Understanding this diagnosis requires differentiating between the various classifications a pathologist may use, as the specific cellular appearance determines any necessary follow-up care.
What Columnar Cell Change Is
Columnar cell change is a physical transformation that occurs within the terminal ductal lobular units (TDLUs), which are the small, milk-producing and carrying structures in the breast. Normally, the inside of these structures is lined by short, cuboidal-shaped cells. In CCC, these cells are replaced by cells that are notably taller and more column-shaped, leading to the designation “columnar”.
The affected lobules often become slightly enlarged or dilated. The columnar cells may arrange themselves in a single layer (columnar cell change) or stack up (columnar cell hyperplasia). These cells frequently exhibit a small, bubble-like protrusion on their surface, referred to as an “apical snout.” This alteration is also commonly associated with tiny deposits of calcium, known as microcalcifications, within the duct spaces.
Understanding the Risk Levels
The clinical significance of a columnar cell lesion depends entirely on whether the cells show signs of abnormality, a feature pathologists call atypia. Columnar cell change or hyperplasia without atypia is generally considered a benign finding that carries only a minimal increase in the relative risk of developing breast cancer in the future. For most individuals, the risk of progression to a more serious lesion is extremely low.
The risk profile shifts when the columnar cells display mild abnormalities, referred to as Flat Epithelial Atypia (FEA). FEA is a specific type of columnar cell change where the cells have slight irregularities in their nuclei and overall appearance. The World Health Organization (WHO) uses FEA as a unifying term for columnar cell change or hyperplasia that exhibits this low-grade cellular atypia.
FEA is categorized as a non-obligate precursor lesion, meaning it is an early step that can potentially lead to low-grade breast cancer, though this progression is rare. While FEA carries a higher risk than benign CCC, it is less concerning than classical Atypical Ductal Hyperplasia (ADH). The presence of atypia is the determining factor, suggesting the cells share molecular characteristics with other low-grade breast lesions.
How Columnar Cell Change Is Identified
Columnar cell change is a microscopic diagnosis, meaning the finding is not visible on a physical exam and rarely causes symptoms. It is typically discovered incidentally during a diagnostic workup that begins with a screening mammogram. The most common imaging finding associated with CCC is the presence of microcalcifications, which appear as tiny white spots on the mammogram film.
When a mammogram identifies suspicious microcalcifications, the next step is usually a core needle biopsy or a vacuum-assisted biopsy. These procedures use a hollow needle to remove small tissue samples from the area of concern, guided by imaging. The tissue samples are then sent to a pathologist who examines them under a microscope.
The pathologist’s examination determines the precise nature of the calcifications and surrounding tissue. This is when the cuboidal cells are observed to be replaced by the elongated, columnar-shaped cells. The final pathology report specifies whether the cells are purely benign (CCC without atypia) or show the mild abnormalities characteristic of Flat Epithelial Atypia.
Follow-Up and Monitoring Recommendations
The recommended clinical management strategy for columnar cell change is based directly on the pathologist’s classification of the cells. When the diagnosis is benign columnar cell change or hyperplasia without atypia, typically no further treatment is required. Individuals with this finding generally return to routine breast cancer screening schedules.
The presence of Flat Epithelial Atypia (FEA) often necessitates a more active approach due to the potential for a co-existing, higher-risk lesion. Since the initial core biopsy only samples a small portion of the tissue, clinicians worry that a more serious lesion, like Ductal Carcinoma in Situ (DCIS), might be present nearby. For this reason, surgical excision of the FEA area is often recommended to ensure the entire lesion is removed and fully evaluated.
Studies show that FEA diagnosed by core biopsy has an “upgrade rate” (finding a more serious lesion during surgery) in the range of 5% to 11.1%. If the entire FEA lesion and associated calcifications are confirmed to have been completely removed during the initial needle biopsy, some specialists may suggest close observation instead of immediate surgery. All individuals with a history of any columnar cell lesion may have personalized surveillance plans put in place, including more frequent clinical breast exams and imaging.