We hear a lot about breast cancer but how much do we really know that explains what we hear? Do you know the different types of breast cancer or what the different stages really mean?

According to the American Cancer Society, breast cancer is broken down into 2 main categories – in situ and invasive. In situ means it is still contained in the infected tissue and invasive means that it has spread to other areas. In situ types are further broken down into the following two types:

• Ductal carcinoma in situ. DCIS (83% of in situ cases diagnosed during 2010-2014) refers to a condition in which abnormal cells replace the normal epithelial cells that line the breast ducts and may greatly expand the ducts and lobules. DCIS may or may not progress to invasive cancer; in fact, sometimes DCIS grows so slowly that even without treatment it would not affect a woman’s health.
• Lobular carcinoma in situ. LCIS (13% of in situ cases) refers to abnormal cells growing within and expanding some of the lobules of the breast. LCIS is generally not thought to be a precursor of invasive cancer, but is a strong risk factor for developing invasive cancer.

Invasive breast cancer makes up about 80% of breast cancers. There are four types of invasive breast cancer:

• Luminal A (HR+/HER2-) (71%). These cancers tend to be slow-growing and less aggressive than other subtypes. Luminal A tumors are associated with the most favorable prognosis, particularly in the short term, in part because they are more responsive to anti-hormone therapy (see page 27).
• Triple negative (HR-/HER2-) (12%). So, called because they are estrogen receptor (ER)-, progesterone receptor (PR)-, and HER2-, these cancers are twice as common in black women as white women in the US, and are also more common in premenopausal women and those with a BRCA1 gene mutation.14 The majority (about 75%) of triple negative breast cancers fall in to the basal-like subtype defined by gene expression profiling.
• Luminal B (HR+/HER2+) (12%). Like luminal A cancers, luminal B cancers are ER+ and/or PR+ and are further defined by being highly positive for Ki67 (indicator of a large proportion of actively dividing cells) or HER2. Luminal B breast cancers tend to be higher grade and are associated with poorer survival than luminal A cancers.
• HER2-enriched (HR-/HER2+) (5%). HER2-enriched cancers tend to grow and spread more aggressively than other subtypes and are associated with poorer short-term prognosis compared to HR+ breast cancers.13 However, the recent widespread use of targeted therapies for HER2+ cancers has improved outcomes for these patients.

Now that you know more about the different types of breast cancers, here is a lesson on how they determine the stage and what the stages of breast cancer are:

“Your pathology report will include information that is used to calculate the stage of the breast cancer — that is, whether it is limited to one area in the breast, or it has spread to healthy tissues inside the breast or to other parts of the body.”

• Stage 0 – Stage 0 is used to describe non-invasive breast cancers, such as DCIS (ductal carcinoma in situ). In stage 0, there is no evidence of cancer cells or non-cancerous abnormal cells breaking out of the part of the breast in which they started, or getting through to or invading neighboring normal tissue.
• Stage I – Stage I describes invasive breast cancer (cancer cells are breaking through to or invading normal surrounding breast tissue) Stage I is divided into subcategories known as IA and IB. Stage IA describes invasive breast cancer in which: the tumor measures up to 2 centimeters (cm) and the cancer has not spread outside the breast; no lymph nodes are involved. Stage IB describes invasive breast cancer in which: there is no tumor in the breast; instead, small groups of cancer cells — larger than 0.2 millimeter (mm) but not larger than 2 mm — are found in the lymph nodes or there is a tumor in the breast that is no larger than 2 cm, and there are small groups of cancer cells — larger than 0.2 mm but not larger than 2 mm — in the lymph nodes…
• Stage II – Stage II is divided into subcategories known as IIA and IIB. In general, stage IIA describes invasive breast cancer in which: no tumor can be found in the breast, but cancer (larger than 2 millimeters [mm]) is found in 1 to 3 axillary lymph nodes (the lymph nodes under the arm) or in the lymph nodes near the breast bone (found during a sentinel node biopsy) or the tumor measures 2 centimeters (cm) or smaller and has spread to the axillary lymph nodes or the tumor is larger than 2 cm but not larger than 5 cm and has not spread to the axillary lymph nodes. In general, stage IIB describes invasive breast cancer in which: the tumor is larger than 2 cm but no larger than 5 centimeters; small groups of breast cancer cells — larger than 0.2 mm but not larger than 2 mm — are found in the lymph nodes or the tumor is larger than 2 cm but no larger than 5 cm; cancer has spread to 1 to 3 axillary lymph nodes or to lymph nodes near the breastbone (found during a sentinel node biopsy) or the tumor is larger than 5 cm but has not spread to the axillary lymph nodes…
• Stage III – Stage III is divided into subcategories known as IIIA, IIIB, and IIIC. In general, stage IIIA describes invasive breast cancer in which either: no tumor is found in the breast or the tumor may be any size; cancer is found in 4 to 9 axillary lymph nodes or in the lymph nodes near the breastbone (found during imaging tests or a physical exam) or the tumor is larger than 5 centimeters (cm); small groups of breast cancer cells (larger than 0.2 millimeter [mm] but not larger than 2 mm) are found in the lymph nodes or the tumor is larger than 5 cm; cancer has spread to 1 to 3 axillary lymph nodes or to the lymph nodes near the breastbone (found during a sentinel lymph node biopsy). In general, stage IIIB describes invasive breast cancer in which: the tumor may be any size and has spread to the chest wall and/or skin of the breast and caused swelling or an ulcer and may have spread to up to 9 axillary lymph nodes or may have spread to lymph nodes near the breastbone. In general, stage IIIC describes invasive breast cancer in which: there may be no sign of cancer in the breast or, if there is a tumor, it may be any size and may have spread to the chest wall and/or the skin of the breast and

the cancer has spread to 10 or more axillary lymph nodes or the cancer has spread to lymph nodes above or below the collarbone or the cancer has spread to axillary lymph nodes or to lymph nodes near the breastbone.

• Stage IV – Stage IV describes invasive breast cancer that has spread beyond the breast and nearby lymph nodes to other organs of the body, such as the lungs, distant lymph nodes, skin, bones, liver, or brain. You may hear the words “advanced” and “metastatic” used to describe stage IV breast cancer. Cancer may be stage IV at first diagnosis, called “de novo” by doctors, or it can be a recurrence of a previous breast cancer that has spread to other parts of the body.

Guys don’t blow this off as not being relevant for two very good reasons. One – the lady in your life could develop breast cancer and the more you know, the better you will be in understanding and helping her through this difficult time. Two – don’t forget that about 2,670 men will be diagnosed with breast cancer this year and about 500 men will die this year from breast cancer. Even though the odds are small, the more you know they better off you will be if you happen to be one of the few.

Ladies, I hope this helps you understand more about breast cancer and helps you as well.