Type and Grade of DCIS

Knowing what type and grade of DCIS you have can help you find the best treatment for you.

There is actually a range of growth from normal cells to abnormal cells—like the steps on a ladder. Normal cells are at the bottom of the ladder; invasive cancer at the top. The range looks like this:

• Normal cells
• Ductal hyperplasia - Too many cells
• Atypical ductal hyperplasia - Too many cells that are starting to appear abnormal (also known as ADH)
• Ductal carcinoma in situ - Too many cells that are growing like a cancer but are still confined to the inside of the duct (DCIS)
• DCIS-MI (DCIS with microinvasion) - Several subtypes of DCIS, some more serious than others
• Invasive ductal cancer - Uncontrolled growth of duct cells that have broken through normal tissue barriers

You may have heard DCIS called "low grade" and "high grade," because these are the "official" definitions of each part of the spectrum. But sometimes it's difficult to figure out where the cells are on this ladder of change from normal to abnormal.

For example, it's sometimes hard for pathologists to tell the difference between ADH — a buildup of cells that look different from normal cells but are not yet growing out of control — and DCIS — a buildup of cells that are growing in an uncontrolled way. In such cases, the term "borderline DCIS" might be used to describe the problem.

The pathologist analyzes the piece of breast tissue removed by a biopsy and describes the type and grade of the DCIS in the pathology report. The grade depends on how the DCIS cells look compared to the nearby normal breast cells.

There are three grades of DCIS:

• low grade, or Grade I
• moderate grade, or Grade II
• high grade, or Grade III

Moderate grade is usually grouped together with low grade. In addition, there are several different patterns of growth: solid, cribriform, papillary, and comedo.

Grade I (low grade) or Grade II (moderate grade) or "non-comedo" DCIS:

Grade I (low-grade) DCIS cells can look very similar to normal cells or ADH cells. Grade II DCIS cells can also be called "moderate grade." These two grades of DCIS tend to grow slowly.

Women with low-grade DCIS are at increased risk of developing invasive disease in the future (after five years), compared to women without DCIS. But compared to women with high-grade DCIS, women with low-grade DCIS have a longer time before a cancer might come back or a new cancer might develop.

There are several patterns of low-grade DCIS:

• Solid DCIS: Cancer cells completely fill the affected breast ducts.
• Cribriform DCIS: There are gaps between cancer cells in the affected breast ducts (like the pattern of holes in Swiss cheese).
• Papillary DCIS: The cancer cells are arranged in a fern-like pattern within the ducts. If the cells are very small, they are called micropapillary.

Solid: There is wall-to-wall cell growth

A Cancer cells

B Basement membrane

Cribriform: There are holes between groups of cancer cells, making it look like Swiss cheese.

A Cancer cells

B Basement membrane

C Lumen (center of duct)

Papillary: The cells grow in fingerlike projections, toward the inside of the duct.

A Cancer cells

B Basement membrane

C Lumen (center of duct)

Grade III (high-grade) DCIS:

In the high-grade pattern, the DCIS cells tend to grow more quickly. Women with high-grade DCIS have a higher risk of invasive cancer, either when the DCIS is diagnosed or at some point in the future. They also have an increased risk of the cancer coming back earlier (within the first five years rather than after five years). High-grade DCIS is sometimes described as "comedo" or "comedo necrosis". Comedo refers to areas of dead (necrotic) cancer cells, which build up inside the tumor. When cancer cells grow quickly, some cells don't get enough nourishment. These starved cells can die off, leaving areas of necrosis.

Comedo: There are areas of "necrosis," which is debris from dead cancer cells; this indicates that a tumor is growing so fast that some tumor cells wither and die because there's not enough blood supply to feed all of them.

A Living cancer cells

B Dying cancer cells

C Cell debris (necrosis)

D Basement membrane