Breast Cancer

What Is Breast Cancer?

Breast cancer is a disease in which abnormal cells in the breast grow uncontrollably and have the potential to invade nearby tissues or spread (metastasize) to other parts of the body. These abnormal cells most often begin in the ducts or lobules of the breast. Breast cancer can occur in both women and men, though it is far more common in women. Early detection and treatment significantly improve outcomes.

Types of Breast Cancer

Breast cancer includes several subtypes based on where the cancer starts and how it behaves:

  • Ductal Carcinoma In Situ (DCIS): Non‑invasive cancer confined to the milk ducts.
  • Invasive Ductal Carcinoma (IDC): Cancer that begins in a milk duct and then invades nearby tissue.
  • Invasive Lobular Carcinoma (ILC): Starts in the milk‑producing lobules and spreads.
  • Triple‑negative breast cancer: A subtype that lacks three common receptor markers and may be more aggressive.
  • HER2‑positive breast cancer: Characterized by overexpression of the HER2 protein.

Each subtype is diagnosed through pathology and may affect treatment planning.

Signs and Symptoms

Breast cancer may not cause symptoms early on. Many cases are identified through routine screening mammograms. When symptoms do occur, they may include:

  • A new lump or thickening in the breast or underarm
  • Change in breast size or shape
  • Nipple discharge (other than breast milk)
  • Inversion of the nipple
  • Skin changes on the breast (dimpling, redness, puckering)
  • Persistent breast pain

Any persistent breast changes should be evaluated by a provider promptly.

Diagnosis and Evaluation

Evaluation of suspected breast cancer typically begins with:

  • Clinical breast exam by a health care provider
  • Mammography to detect abnormalities
  • Breast ultrasound to further characterize a finding
  • Biopsy to obtain tissue for microscopic analysis and confirm the diagnosis

Pathology reports usually include information about the tumor type, hormone receptor status, and other markers that guide treatment decisions.

Treatment Options

Breast cancer treatment depends on the stage and subtype of the cancer as well as patient preferences. Common treatments include:

  • Surgery: Lumpectomy (breast‑conserving surgery) or mastectomy to remove cancerous tissue.
  • Sentinel lymph node biopsy or axillary lymph node dissection to assess spread.
  • Radiation therapy following surgery to reduce local recurrence risk.
  • Systemic therapy: Chemotherapy, hormone therapy, targeted therapy, and immunotherapy depending on tumor biology.

Multidisciplinary coordination among surgical, medical, and radiation oncology teams helps tailor the best treatment plan.

Divisions Involved in Your Care

Procedures We Use

Frequently Asked Questions

Any new lump or persistent change in the breast warrants prompt evaluation by a health care provider. Early assessment helps determine if further imaging or biopsy is needed.

Early detection through screening increases the likelihood that cancer is found at an early stage when treatment is most effective and may reduce the need for more extensive surgery.

Yes. Although uncommon, breast cancer can occur in men. Any persistent breast changes in men should be evaluated.

Treatment may include surgery, radiation, chemotherapy, hormone therapy, or targeted therapy — often in combination — depending on the stage and subtype of cancer.

Not always. Many patients with early‑stage breast cancer may be candidates for breast‑conserving surgery (lumpectomy) with radiation. The choice depends on tumor size, location, patient preference, and other clinical factors.

Staging is based on tumor size, lymph node involvement, and whether the cancer has spread to distant organs. Staging helps guide treatment planning and prognosis.