Questions for surgeon and oncologist

Yes, unless you are older (75+) with other health problems that would make surgery unusually risky, surgery will be your best option for the reason you stated - there might be invasive cancer hiding in there and there is no way to know without removing it. The chances are higher with intermediate/high grade like you have.

As far as questions, I think you are on the right tack - it's important to know size and location so that you can make decisions about what type of surgery is most appropriate for you, and ER/PR receptors so you can consider whether anti-hormonal therapies are an option. Be sure when you are discussing surgery to ask about what follow-up treatments would go along with each, as well as what the chances of recurrence and/or new primaries are with and without each. For example, especially at your age, lumpectomies are usually followed by radiation, while mastectomies rarely are. If your cancer is ER/PR+, then assuming that at 40 you are premenopausal, Tamoxifen might be an option, but whether it's recommended might also depend on the surgery - a lumpectomy leaves more breast tissue behind in need of protection, but a double mastectomy would probably need no further treatment.

For what it's worth, I chose a lumpectomy, had radiation and am in my 4th year of Tamoxifen and have tolerated it all quite well. Other people in a similar situation have made different decisions and are just as happy with their choices, so there is no one right answer - it's a matter of gathering all the information you can and then making an informed decision that is right for you.

Best of luck as you go through this process!

Standard of care recommends radiation for anyone younger than I think 70 following a lumpectomy, but increasingly more doctors are willing to let younger patients forgo it, especially if they have low grade DCIS and wide surgical margins. It’s something you can certainly discuss with your treatment team.

In addition to the Layperson's Guide (original post in the link provided above by LisaAlissa), see also:

Lumpectomy vs Mastectomy Considerations (see Jun 14, 2013 post from Beesie

https://community.breastcancer.org/forum/68/topics/806074?page=1#post_3589278

DCIS and "Standard of Care":

As noted in a May 2016 letter in J. Clin. Oncol. by Shah et al., "At this time, adjuvant radiation therapy remains the standard of care for most women with DCIS following breast-conserving surgery. However, to the extent that clinical consensus guidelines reflect current standards of care, I note that lumpectomy without radiation is included in the NCCN guidelines, and thus, in the appropriate case, may be considered to be within the current standard of care.

The NCCN guidelines for Breast Cancer (Version 2.2017) do include lumpectomy without radiation as a primary treatment option in the appropriate case, based upon lower-level evidence:

"Lumpectomy [e,f] without lymph node surgery [g] without radiation therapy [h,i,j,k,l] (category 2B)"

"Category 2B: Based upon lower-level evidence, there is NCCN consensus that the intervention is appropriate."

By comparison, the option of Lumpectomy (without lymph node surgery) + whole breast radiation therapy is a Category 1 recommendation: "Based upon high-level evidence, there is uniform NCCN consensus that the intervention is appropriate."

NCCN guidelines further note:

"Whole-breast radiation therapy following lumpectomy reduces recurrence rates in DCIS by about 50%.*** Approximately half of the recurrences are invasive and half are DCIS."

Regarding the factors affecting local recurrence risk, they note:

"A number of factors determine local recurrence risk: palpable mass, larger size, higher grade, close or involved margins, and age <50 years."

A recent ASCO guideline applicable to those with DCIS receiving breast conserving surgery and whole breast irradiation similarly notes:

ASCO (Morrow, 2016): http://ascopubs.org/doi/pdf/10.1200/JCO.2016.68.3573

"Young patient age has consistently been associated with IBTR [ipsilateral breast tumor recurrence], and tumor factors such as histologic pattern, comedo necrosis, and nuclear grade and size of DCIS also modify the risk of IBTR.[17,26,27] More recently, unfavorable gene profile scores [from the OncotypeDX test for DCIS] have also been associated with IBTR.[28,29] "

Per the NCCN guidelines discussion, "[t]he option of lumpectomy alone should be considered only in cases where the patient and the physician view the individual as having a low risk of disease recurrence." However, in practice, it has been difficult to identify criteria which can be used to reliably select patients at low risk.

With the pathology findings from all biopsies and surgeries in hand and a pathologic diagnosis of pure DCIS (Stage 0), a Radiation Oncologist can provide expert professional guidance about the risks and benefits of radiation therapy, impact on reducing in-breast recurrence (invasive or DCIS), and insight into individual recurrence risk profile. The patient's risk tolerance is also factor.

Hoping for the best possible pathology results for melrose7.

BarredOwl

***The 50% reduction benefit is a "relative risk reduction" benefit. The absolute benefit at the individual level depends on estimated local recurrence risk and should be discussed with a Radiation Oncologist.