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Breast cancer

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Invasive ductal carcinoma

Invasive ductal carcinoma, also called infiltrating ductal carcinoma or ductal adenocarcinoma, is the most common type of invasive breast cancer. It accounts for up to 80% of all invasive breast cancers.

Invasive ductal carcinoma starts in the breast ducts but grows through the duct wall and spreads into nearby breast tissue. The cells can continue to grow and cause a lump or thickening in the breast. The breast cancer cells can also spread (metastasize) to the lymph nodes and other parts of the body.

Invasive ductal carcinomas frequently have some ductal carcinoma in situ (DCIS) cells in areas of the tumour. The presence of these DCIS cells suggests that DCIS may develop into an invasive tumour.

Invasive ductal carcinoma may be further classified as:

  • invasive, not otherwise specified (NOS) or no special type (NST)
    • This is the most common type of invasive ductal carcinoma.
  • invasive with predominant intraductal component
  • mucinous (colloid)
    • This type of invasive ductal carcinoma is slow growing and less likely to spread to the lymph nodes.
  • papillary
    • The cells grow in a fern-like pattern.
    • It is generally slow growing and rarely spreads to the lymph nodes.
  • tubular
    • The cancer cells form in tube-like structures.
    • It rarely recurs after treatment.
  • medullary
    • The tumour has larger cells, well-defined borders and may contain white blood cellswhite blood cellsA type of blood cell that helps the body fight infection and diseases..
    • It rarely spreads to the lymph nodes.
  • scirrhous
    • The cells are surrounded by thick bundles of fibres.
    • It may be an aggressive, fast-growing tumour.
  • other

The treatment for all types of ductal carcinoma is the same. Surgery is the most common treatment.


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