What should you know about invasive DCIS treatment?

DCIS remains inside a milk duct. An invasive component has moved through the duct wall into nearby breast tissue, so the team assesses both the in-duct area and the invasive cancer. The pathology report may describe grade, margins, hormone receptors and HER2, all of which can influence the plan.

A mammogram can show the area of concern, while biopsy confirms the cell type. Examination and selected imaging help the team decide whether lymph nodes require assessment. These steps separate local treatment decisions from medicines that treat cancer cells throughout the body.

Surgery may be a lumpectomy or mastectomy, with the choice influenced by the area’s size and location, the amount of breast tissue involved, inherited risk and personal preference. Radiotherapy is often considered after breast-conserving surgery. Hormone therapy may be offered when the cancer has hormone receptors. Some invasive cancers also need additional systemic treatment; your team will match this to the pathology and staging.

After a biopsy or operation, call the care team for worsening redness, warmth, drainage, fever, uncontrolled pain or swelling of the arm. Seek emergency help for heavy bleeding, chest pain, difficulty breathing or sudden neurological symptoms. Before treatment, report a rapidly changing breast or underarm lump without waiting for a routine appointment.

Ask which part is DCIS and which part is invasive, whether the margins and lymph nodes are clear, why a lumpectomy or mastectomy is recommended, whether radiotherapy or hormone therapy is needed, and how treatment could affect sensation, movement and future breast imaging.