Different DCIS Grades In Same Breast?

Hi wiseseeker:

Sorry about your recent diagnosis. It is possible to have different grades or even different types of disease present. I had a mixture of Grade 2 and grade 3 DCIS on biopsy. In my case, surgery revealed some small areas of invasion (IDC, 1.5 mm and microinvasion), which was not entirely surprising as invasive cancer is reported in ~ 10% to 20% of DCIS cases diagnosed by minimally invasive biopsy, approximately half of which are limited to microinvasive cancer.

Please note that grade does not drive the choice between lumpectomy and mastectomy. In general, it is the extent and/or location(s) of disease (of any grade) within the breast and/or relative to the size of the breast that may limit options up front. Even those diagnosed with invasive disease (e.g., IDC) can elect lumpectomy plus radiation in the appropriate case. With DCIS or invasive disease, re-excision may be needed to obtain adequate margins. Occasionally, lumpectomy and re-excision(s) reveal that disease is more extensive than appreciated from imaging, resulting in mastectomy.

As you can appreciate from your experience firsthand, it is not possible to predict with certainty whether suspicious calcifications are benign or malignant. Your breast surgeon will consider the imaging results and make a recommendation in their best medical judgment about whether they feel lumpectomy is a suitable option for you or not. You may wish to request an MRI, which is generally a very sensitive imaging technique (but as a result, can have a higher rate of false positives). As DCIS is not an emergency, you may also wish to seek a second opinion regarding your diagnosis and surgical options at an independent institution, which may include a review of all imaging and the pathology slides.

Many new members find these comprehensive posts from Beesie to be extremely helpful. You may wish to bookmark them and read them over and over as you move forward, because it is a large amount of information to absorb.

A layperson's guide to DCIS (scroll up to the original post):

https://community.breastcancer.org/forum/68/topic/...

Lumpectomy vs Mastectomy Considerations (see Jun 20, 2013 post from Beesie

https://community.breastcancer.org/forum/91/topics/806452?page=1#post_3598134

Good luck!

BarredOwl

Hi wiseseeker:

MRI is quite likely to reveal the presence of malignant disease (DCIS and/or invasive disease). However, MRI cannot distinguish between the presence of in situ or invasive disease. Pathologic examination (of biopsy or surgical samples) is required to tell what type of malignancy is present.

While MRI is considered to be the most sensitive imaging modality, it is not 100% perfect in identifying the presence of malignancy. This 2014 article discusses some of the capabilities and limitations of MRI:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC428686...

"DCIS is commonly diagnosed by mammography screening. The mammographic features of DCIS are well known. Typically clustered microcalcifications are common in 85-90% of the cases (Evans et al., 1999). Potential findings include circumscribed masses, focal nodular patterns, asymmetry, dilated retroareolar ducts, ill-defined, rounded tumour, focal architectural distortion, subareolar mass and developing density, but they are less common (Ikeda and Andersson, 1989). Up to 20% of DCIS remain mammographically occult [not visible on mammography] due to the lack of calcifications and/or small tumour dimensions. Breast MRI has a high sensitivity in the diagnosis of invasive breast cancer, varying from 90% to 100%; the sensitivity for the diagnosis of DCIS is 77-96% (Nadrljanski et al., 2013). The sensitivity of mammography decreases with increasing nuclear grade, whereas that of MRI is improved. In a prospective study mammography missed nearly half of the high-grade lesions (48%) (Kuhl et al., 2007). The fact that MRI detects many DCIS lesions that go unnoticed on mammography implies that some cancers can be prevented by timely intervention on the basis of MRI finding. The disadvantages of MRI are the limited availability and the high cost. For the time being, the primary role of MRI in DCIS is limited to the evaluation of lesion extension and thus the planning of breast-conserving surgery (BCS)."

The disease on my right was clearly evident by mammography (biopsy showed DCIS), and the extent of disease was confirmed by MRI. Neither modality was able to distinguish between DCIS versus IDC. Pathological examination (by biopsy or surgery) was necessary to identify the type of disease that was present (DCIS and IDC).

My left side illustrated the relatively unusual and small proportion of DCIS cases that are not detectable by MRI. An MRI-guided biopsy on the left was benign, and the rest of the left side appeared to be clear by MRI. However, mammography showed a subtle area of concern, which excisional biopsy showed to be DCIS.

In my case, extensive DCIS on the right meant right mastectomy. On the left, I knew that the MRI could not see the biopsy-proven DCIS on the left side. Because of that and because mammography was clearly limited by extreme density, I chose left mastectomy also. Surgical pathology revealed extensive DCIS on the left as well, so in my case, it turned out to be the correct decision.

Everyone is different, and if lumpectomy (plus radiation, if indicated) is a reasonable option for you based on expert review of your imaging, it can be an excellent choice. You can request a complete copy of the radiologist's reports from all imaging to date to see if it the MRI findings are in agreement with the mammography findings, and to confirm that the MRI identified known areas of biopsy-established disease in your case. You can also ask your breast surgeon this question (Are the mammography and MRI findings concordant?), and whether there are limitations in estimating the extent of disease in your case (e.g., extremely dense; heterogeneously dense).

Keep in mind, that even if a small microinvasion is found upon surgery, the prognosis (and treatment) is generally very similar to DCIS.

BarredOwl

Age 52 at diagnosis - Synchronous bilateral breast cancer - Stage IA IDC - BRCA negative;

Bilateral mastectomy and SNB, without reconstruction 9/2013

Dx Right: ER+PR+ DCIS (5+ cm) with IDC (1.5 mm) and micro-invasion < 1 mm; Grade 2 (IDC); 0/4 nodes.

Dx Left: ER+PR+ DCIS (5+ cm); Grade 2 (majority) and grade 3; isolated tumor cells in 1/1 nodes (pN0i+(sn)).