DCIS

[Ginnie74]

What is the percentage of DCIS becoming invasive?  I am 74 years old with a pacemaker and was just diagnosed with DCIS - high grade - in two different areas.. I read where the DCIS mutates into invasive cancer in 25% to 50% of cases.  It seems that, at worst, I have a 50% chance of having invasive cancer.  I have read elsewhere that it will "most certainly" progress into invasive cancer.  My doctor recommends a mastectomy but would do lumpectomies, which is what I prefer.  I'm concerned about the effect on my pacemaker.  Also, I'm extremely sensitive to drugs, and I know the mastectomy may cause considerable pain.  Thank you in advance for your answers.

[Fernando Roque, MD]

Hi. The risk that a high grade DCIS occurring in multiple areas will later develop into invasive cancer is very high, so I suggest that you proceed with the mastectomy.  I think that your pacemaker can easily be relocated somewhere else if it's presently underneath the breast that needs to be operated on.  If a mastectomy is done, you would not need to have chemotherapy or radiation treatment after the surgery.  If you take the option of lumpectomy, you probably need to have radiation treatment after the operation.  If your cancer turns out to be hormone receptor positive, it would also be advisable for you to take hormonal treatment (e.g. Tamoxifen or an aromatase inhibitor such as Anastrozole) to help prevent the risk of recurrence.