FAQs: Breast Cancer: BRINSITU

UNDERSTANDING YOUR PATHOLOGY REPORT: A FAQ SHEET

When your breast was biopsied, the piece(s) of tissue that were taken were sent to be studied under the microscope by a specialized doctor with many years of training called a pathologist. After the tissue is prepared and microscopic slides made, the pathologist studies the tissue and makes a diagnosis based on what s/he sees on the slides. The pathologist then reports to your treating doctor the diagnosis for each of the tissue in a pathology report to help manage your care. This FAQ sheet is designed to help you understand the medical language used in the pathology report.

1. What is "in-situ carcinoma"?

Breast cancer has two major stages, an early stage when cancer can not spread to other parts of the body and a later stage when can spread outside the breast. The earlier stage is called In-situ carcinoma. The later stage is known as invasive or infiltrating carcinoma. Because cancer is defined as a malignant tumor that has the ability to spread beyond the breast, sometimes in-situ carcinoma is considered a pre-cancer because it hasn't spread. The normal breast is made of tubes lined with cells similar to skin cells. These tubes are called ducts. Beginning at the nipple, these ducts branch many times like a tree and end in a group of blind-ending sacs called lobules or lobular units. The lobular unit has special cells that make milk. When a baby is nursing, the lobular units grow bigger to make enough milk for the baby. The ducts provide a channel or tube to bring the milk to the nipple for a baby to drink. The lobular units and the very ends of the ducts near the lobular units are where early cancers begin. The early cancers grow, filling a lobule and the nearby duct and causing them to expand like small balloons. As the duct and lobule is stretched by the cancer cells, the walls of the lobule and duct are injured by the carcinoma cells. At some point in their growth, many of these early cancers break through the walls and spread into the breast tissue outside the ducts and lobules. As long as the sarcinomas have not broken out of these structures and are still confined to the breast ducts or lobules, they are considered "in-situ carcinoma." Once in-situ carcinoma has broken out of the ducts or lobules it is referred to as "invasive" or "infiltrating" carcinoma.

2. What does it mean if my in-situ carcinoma is called "ductal carcinoma in-situ", "intraductal carcinoma", "lobular carcinoma in-situ" or "in-situ carcinoma with duct and lobular features" ?

In-situ carcinomas of the breast have a variety of appearances under the microscope. The two major patterns seen in breast in-situ carcinoma are ductal carcinoma in-situ (DCIS) or lobular carcinoma in-situ (LCIS). "Intraductal carcinoma" is the same as "ductal carcinoma in-situ". In some cases, the in-situ carcinoma can have both duct and lobular features and in some cases DCIS and LCIS may both be present at the same time.

3. What does it mean if my report mentions E-cadherin.

E-cadherin is a test that the pathologist uses to help determine if the carcinoma in-situ is ductal or lobular. If your report does not mention E-cadherin, it means that this test was not necessary to make the distinction.

4. What does it mean if my ductal carcinoma in-situ is described as being "cribriform", micropapillary", "apocrine", "comedo", "with comedonecrosis", "papillary", or "solid"?

These are different patterns of ductal carcinoma in-situ seen under the microscope.The appearance may influence the treatment that your doctor recommends.

5. What does it mean if my ductal carcinoma in-situ is described as being "low grade", "intermediate grade", or "high grade", or "nuclear grade 1", "nuclear grade 2", or "nuclear grade 3", or "low mitotic rate", "intermediate mitotic rate", or "high mitotic rate"?

These are all different ways of describing ductal carcinoma in-situ (DCIS) seen under the microscope. DCIS which is high grade, nuclear grade 3, or high mitotic rate are associated with an increased risk of coming back (recurring) following local excision and may affect subsequent therapy.

6. What is the significance of the reported size of the ductal carcinoma in-situ (DCIS)?

The pathologist typically will measure on an excision specimen the greatest dimension of the DCIS tumor as seen under the microscope or by gross (naked eye) examination (if visible). Another way to measure DCIS is to note the number of slides that contain DCIS. On needle biopsy, DCIS is typically not given a measurement, as the more accurate measurement will be done on the subsequent excision (lumpectomy or mastectomy). The more extensive the DCIS there is an increased risk of the tumor coming back (recurrence) and may affect subsequent therapy.

7. What is the significance of ductal carcinoma in-situ (DCIS) in terms of prognosis and treatment?

DCIS is a pre-cancer but its natural history is not well understood. Treatment is aimed at getting rid of all the DCIS usually by surgery but also in some cases with the addition of radiation (radiotherapy, or hormonal therapy in order to prevent the DCIS from coming back (recurring) and also from developing into invasive carcinoma.

8. What does it mean if my report mentions special studies such as high molecular weight cytokeratin (HMWCK), ck903, ck5/6, p63, muscle specific actin, smooth muscle myosin heavy chain, calponin, or keratin?

These are special tests that the pathologist sometimes uses to help make the diagnosis of ductal carcinoma in-situ. Not all cases need these tests. Whether your report does or does not mention these tests has no bearing on the accuracy of your diagnosis.

9. What does it mean if my report on ductal carcinoma in-situ (DCIS) mentions "estrogen receptor (ER)" or "progesterone receptor (PR)"?

ER and PR are special tests that the pathologist does that are important to predict response of the DCIS to certain types of therapy. Results for ER and PR are reported separately and can be reported in different ways: 1) negative, weakly positive, positive; 2) percent positive; 3) percent positive and whether the staining is weak, moderate, or strong. How the results of your tests will affect your therapy is best discussed with your treating physician.

10. What if my report on ductal carcinoma in-situ (DCIS) mentions "margins" or "ink"?

When an excisional biopsy (lumpectomy) is performed, the pathologist coats the outer aspect of the specimen with ink, sometimes different colored ink. If an abnormal growth (ie. in-situ carcinoma) extends to the ink, it indicates that it may not have been completely removed. Typically additional treatment (surgery, radiation, or hormone therapy) is used to get rid of the residual DCIS. Management of DCIS at a margin is best discussed with your treating physician.

11. What is the significance of lobular carcinoma in-situ (LCIS) in terms of prognosis and treatment?

The presence of LCIS increases the risk of subsequently developing carcinoma in both breasts. Typically LCIS found on excision is managed with observation and in some cases with hormone therapy. If LCIS is found on needle biopsy, in some cases excision may be recommended if the LCIS does not account for the mammographic findings or if the LCIS is pleomorphic or with necrosis (see below). LCIS found on needle biopsy is an area of uncertainty and is best discussed with your treating physician.

12. What does it mean if my report mentions "lobular neoplasia"?

For many years, women who had lobular carcinoma in situ in their breast biopsies had no further surgeries. We know through long term studies of these women that most do not ever develop an invasive carcinoma. Because of this finding, many doctors prefer the term lobular neoplasia since this disease does not inevitably become invasive.

13. What if my lobular carcinoma in-situ (LCIS) is described as "pleomorphic" or "with necrosis"?

These types of LCIS may be more aggressive and associated with an increased risk of carcinoma when compared to LCIS without these features.

14. What if my report on lobular carcinoma in-situ (LCIS) mentions "margins" or "ink"?

When an excisional biopsy (lumpectomy) is performed, the pathologist coats the outer aspect of the specimen with ink, sometimes different colored ink. If an abnormal growth (ie. in-situ carcinoma) extends to the ink, it indicates that it may not have been completely removed. Even if LCIS extends to the ink, it is typically not treated with further excision. However, in some cases, such as pleomorphic LCIS, LCIS with necrosis, or LCIS that make a mass that is palpable or seen on mammography it may be treated with additional excision. The management of LCIS at a margin is best discussed with your treating physician.

15. What does it mean if my report also mentions "atypical ductal hyperplasia (ADH)" or "atypical lobular hyperplasia (ALH)"?

These are precursors to ductal carcinoma in-situ and lobular carcinoma in-situ, respectively. These typically are of no importance when seen on needle biopsy or excision if there is in-situ cancer elsewhere on the sampling.

16. What does it mean if my report also says any of the following terms: "usual duct hyperplasia", "adenosis", "sclerosing adenosis", "radial scar", "complex sclerosing lesion", "papillomatosis", "papilloma", "apocrine metaplasia", "cysts", "columnar cell change", "collagenous spherulosis", "duct ectasia", "fibrocystic changes", "flat epithelial atypia", or "columnar cell change with prominent apical snouts and secretions (CAPSS)"?

All of these terms are non-cancerous things that the pathologist sees under the microscope and are of no importance when seen on a biopsy where there is in-situ cancer.

17. What does it mean if my report mentions "microcalcifications" or "calcifications"?

Microcalcifications or calcifications are minerals that are found in the both noncancerous and cancerous breast lesions and can be seen both on mammograms and under the microscope. They are reported by the pathologist to show that the abnormal area seen in the mammogram was successfully sampled by the biopsy. By themselves, they do not have any significance.