Ductal Carcinoma In Situ (DCIS) basically means breast cancer cells that are confined within the breast ducts.

Although the cells are cancerous, they have not broken through (or invaded) the layer surrounding the duct (basement membrane).

Invasion of this basement membrane is defined as an invasive cancer.

Thus, DCIS cells cannot spread into the lymphatics or blood stream as they are still confined by this basement membrane.

Although we do not have proof of DCIS becoming cancer, it is very likely that if DCIS progresses, it will invade the basement membrane and turn into invasive cancer.

Also, although the biopsy may show DCIS only, there may be other associated invasive disease next to it which may only be seen after the whole lump has been removed.

How is it treated?

DCIS is usually treated with surgery with or without adjuvant radiotherapy. Adjuvant chemotherapy and endocrine therapy are not required.

  • Surgery is usually performed by removing the area of DCIS (lumpectomy / Wide local excision) with or without breast reduction (Oncoplastic surgery) OR removing the breast (mastectomy) which can be done with or without immediate or delayed reconstruction (making a “new breast” with an implant or with your own tissue).
  • Surgery may include removing a group of lymph nodes called the sentinel nodes (sentinel node biopsy) if the DCIS is forming a lump, is quite large or requires a mastectomy.
  • This is the use of x-rays to the breast to reduce the risk of recurrent DCIS or cancer in the same breast.
  • It is usually required after a lumpectomy but can be omitted for very small areas or low grade (less aggressive) DCIS.
  • Radiotherapy is commonly administered over 3-5 weeks and is usually given every weekday (Mon to Fri). The radiation itself is given over a couple of minutes.
  • Patients can usually fit this around their work schedule.
  • Planning, duration and side effects are all discussed in detail by the Radiation Oncologist.

Your treatment team includes: surgeon, radiation oncologist, medical oncologist, breast care nurse as well as other members of the multidisciplinary team such as the radiologist, pathologist and clinical geneticist.

Follow up is usually by the surgeon and may be shared with your local doctor (Shared Care)

  • Every 3-6 months in the first three years.
  • Every 6-12 months in the next two years.
  • Annually thereafter.
  • Your breast imaging (mammogram +/- ultrasound) should be performed on an annual basis indefinitely.

After the first 5 years of follow up, you may be discharged to your GP for annual examination and surveillance imaging. However, you may return to Breastscreen for your annual mammogram. You may also continue your surveillance through your surgeon.