Treating Ductal Carcinoma In Situ (DCIS)

Ductal carcinoma in situ (DCIS) is a confusing diagnosis for many women. The very good news is that DCIS is not invasive cancer. By definition, the involved cells have not left the ducts and do not have the ability to spread further. A similar situation is Lobular carcinoma in situ (LCIS) where the cells remain in the lobes.

DCIS is classified as Stage 0, and some doctors do not consider it to be cancer. In my experience, however, virtually all women with this diagnosis feel as though it is breast cancer and react accordingly. The first hours or days after hearing the news feel like the crisis of invasive breast cancer, and almost all women are very distressed. Hopefully, as a little time passes, that upset subsides and the right treatment decisions can be made.

Decades ago, when I first began to do this work, DCIS was always treated with a mastectomy. This was especially perplexing to women who wondered why, since this wasn't cancer, they needed a mastectomy while many women with invasive breast cancer were offered the option of a lumpectomy and radiation. This changed a long time ago, and many women with DCIS are also able to avoid losing a breast. If the DCIS is wide spread throughout the breast, a mastectomy may still be necessary in order to fully remove it all. Your surgeon will usually be able to make this decision based on a mammogram or MRI; sometimes it only becomes clear when it is impossible to achieve clean margins during surgery.

Women who are diagnosed with DCIS may be referred for genetic testing to assess the presence of a BRCA mutation. This recommendation is usually based on family history and should be part of the early conversation. If a mutation is identified, it is likely that the treatment recommendation will be bilateral mastectomies — just as it would be with a diagnosis of invasive breast cancer. Also similarly, there is usually the second choice of surgery to deal with the known problem and then proceeding with careful monitoring, annual mammograms and breast MRIs. If you are diagnosed with either DCIS or invasive breast cancer and have a BRCA mutation, it is important to understand and carefully consider your surgical choices. To make the best decision for yourself, it can be helpful to speak with an oncology social worker or another therapist who is well-informed about this situation.

The second part of treatment for DCIS is considering taking tamoxifen, an anti-estrogen or hormonal treatment. This is a daily pill that is usually continued for five years and reduces the risk of future breast cancers for some years after that period. There are currently studies underway to compare the efficacy of the tamoxifen pill to a new tamoxifen gel, but there won't be answers for some time. As is the case for the treatment of invasive cancer, post-menopausal women are often prescribed one of the aromatase inhibitors (AIs) in lieu of tamoxifen. This is a conversation that usually happens with a medical oncologist.

If you are diagnosed with DCIS or LCIS, remind yourself that this is the best possible diagnosis in the breast cancer spectrum. You will be fine.