SNB for DCIS grade 1?

I think the issue is at the moment you have been scheduled for a lumpectomy. After the pathology comes back and they find your area of concern to only be DCIS with clean margins then chances are you will be through, or maybe hormonal therapy. No SNB , no fear of lymphodema.

If an invasive component is found then a SNB can be done to see if the cancer has spread to the nodes.

This would be the least invasive treatment plan.

Good luck making your decisions.

Hi JACTsMom:

Question 1: If I have the SNB and it's negative does that mean I can forego radiation?

No. Sentinel node biopsy is a form of axillary staging, and assesses regional [edited to add: spread and risk of ] distant spread. Radiation therapy to the breast itself is a local treatment, and can be separately warranted regardless of nodal status, based on the results of the surgical pathology of the breast tissues (e.g., if higher risk DCIS or invasive disease is found).

If no invasive disease is found, then your doctors will consider all relevant clinico-pathologic information, such as the size, grade, hormone receptor status, margins, your age, etc., and Oncotype for DCIS test results (if used), in order to assess your recurrence risk without radiation. You can consider your risk/benefit profile and come to decision about radiation then.

Question 2: If I have the LX only and it ends up showing IDC do I need the SNB at a later date?

Sentinel node biopsy is indicated for invasive disease, and can be done in a later procedure. The information is used (along with other information) for assessing the need for adjuvant therapy. With lumpectomy, if adequate margins are not achieved, a second procedure may be needed anyway.

Additional Information:

To my knowledge, current US consensus practice guidelines from the National Comprehensive Cancer Network (NCCN) and American Society of Clinical Oncologists (ASCO) generally do not recommend SNB for a patient undergoing breast conserving therapy ("BCT", lumpectomy) for pure DCIS (any grade; no invasive disease present). Note that in certain cases, it may be appropriate to depart from what the guidelines provide.

Under the NCCN guidelines for breast cancer (Version 1.2016), the lumpectomy options do not include sentinel node biopsy, except in the case of excision in an anatomic location (eg, tail of the breast), which could compromise the performance of a future sentinel lymph node (SLN) procedure, in which case an SLN procedure may be considered:

Lumpectomy without lymph node surgery + whole breast radiation therapy (category 1)

OR

Lumpectomy without lymph node surgery without radiation therapy (category 2B)

The ASCO guideline does not recommend routine SNB for patients with DCIS undergoing lumpectomy either:

http://jco.ascopubs.org/content/32/13/1365.full

"For women with a minimally invasive biopsy showing [pure] DCIS who are being treated with BCS [lumpectomy], there is no evidence to support performing SNB (see Recommendation 4.3). Performing SNB places patients at risk for long-term complications including permanent lymphedema. SNB may be performed as a separate second procedure in the women in whom invasive cancer is found (reported in 10% to 20% of cases overall, approximately half of which are limited to microinvasive cancer). Exceptions may include [note: these may be optional] cases where breast imaging or physical examination show an obvious mass characteristic of invasive cancer or a large area of calcification without a mass (eg, ≥ 5 cm) where the probability of finding invasive cancer on the resection specimen is high . . . These recommendations are primarily based on retrospective data. Therefore, the Update Committee does not endorse routine SNB for patients with DCIS undergoing BCS."

This 2012 abstract discusses apparent overuse use of the procedure in light of the guidelines:

http://meetinglibrary.asco.org/content/100421-114

The abstract concludes: "SLNB can be performed as a second procedure for those treated with BCS and identified with invasive cancer, thereby avoiding unnecessary risk of significant morbidity. Breast programs should review their practices to curtail the use of unnecessary surgery for women with DCIS."

In other words, in appropriate cases, one can choose to have the lumpectomy for DCIS, obtain review of the final pathology, and if invasion is found, then undergo SNB in a second (later) procedure. If there is no invasion, the patient is able to avoid the SNB procedure and its accompanying risks, including the risk of lymphedema. Lymphedema can occur in some cases with SNB (estimates of incidence vary), the risk of it showing up is a life-long risk (it may appear years later), and once it appears, it is a life-long condition. Again, most lumpectomy patients can avoid SNB completely, or at least defer it until it is clearly medically indicated.

With BCT (lumpectomy), if clean margins are not obtained, a further procedure(s) may be needed anyway, so presumably you are willing to undergo a second procedure in general, and have no contraindication for a second procedure (which entails another round of some type of anesthesia, etc.)

I had mastectomy with SNB on both sides (indicated under guidelines). While I do not appear to have lymphedema so far, my body did not like the lymph node surgery at all. I had serious problems with my arms requiring physical therapy, axillary cording lasting for months, and my arms still bother me over two years later. I try to take lymphedema precautions, and I worry about it.

BarredOwl

I think BarredOwl’s post is very good. I did have a SNB with my lumpectomy, but only because the micro-invasion of IDC had been found in the stereotactic biopsy. Had that not been the case, I wouldn’t have done it. I haven’t had problems with lymphedema, but I did have axillary cording for months, like Barred Owl.