Ductal Carcinoma

Definition

Ductal carcinoma is the most common type of breast cancer, starting in the cells that line the milk ducts. It includes two main forms: ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC).

Characteristics

• DCIS is a non-invasive cancer where abnormal cells are confined to the ducts and haven’t spread to nearby tissue.
• IDC is invasive, meaning the cancer has spread beyond the ducts into surrounding breast tissue. IDC accounts for about 80% of all breast cancers.

Symptoms may include a breast lump, nipple discharge, or changes in breast shape or skin, though DCIS often causes no symptoms and is found during routine screening.

Diagnosis and Prognosis

Diagnosis involves mammograms, ultrasound, MRI, and biopsy. Prognosis for DCIS is excellent with early treatment. IDC prognosis depends on stage, tumor size, lymph node involvement, and receptor status (e.g., hormone or HER2).

Treatment

DCIS is usually treated with surgery (lumpectomy or mastectomy), often followed by radiation. IDC may require a combination of surgery, radiation, chemotherapy, hormone therapy, or targeted therapy, depending on tumor characteristics.

Last Revised: 12 May , 2025