What is Breast Cancer

To understand breast cancer, it’s first important to understand what cancer is: basically, the production of abnormal cells.

Learn more about Sarah Cannon's proactive approach to breast cancer detection.

The body is programmed to routinely replenish cells in different organs. As normal cells age or get damaged, they die off. New cells take their place. This is what’s supposed to happen. Abnormal cell growth refers to a buildup of extra cells. This happens when:

  • New cells form even though the body doesn’t need them or
  • Old, damaged cells don’t die off.

These extra cells slowly accumulate to form a tissue mass, lump, or growth called a tumor. These abnormal cells can destroy normal body tissue and spread through the bloodstream and lymphatic system.

The first thing to understand is that the growth in your breast can be either benign or

malignant. You’ve probably heard these terms. Here’s exactly what they mean:

  • Benign: means not cancerous. A benign tumor can get larger but does not spread to other tissues or organs.
  • Malignant: means cancerous. The cells of a malignant tumor can invade nearby tissues and organs and spread. They are destructive.

Look at the chart below to learn more about the difference in benign and malignant.

Benign tumors:

  • Can be removed
  • Usually don’t grow back
  • Are rarely fatal
  • Don’t spread to other tissues or body parts

Malignant tumors:

  • Can often be removed
  • Sometimes grow back
  • Can invade other tissues and organs and cause damage
  • Can spread to other body parts
  • Can be fatal

Inside a woman's breast are 15 to 20 sections called lobes. Each lobe is made of many smaller sections called lobules. Lobules have groups of tiny glands that can make milk. Fat and fibrous tissue fills the spaces between the lobules and ducts.

The breasts also contain lymph vessels. These vessels are connected to small, round masses of tissue called lymph nodes. Groups of lymph nodes are near the breast in the underarm, above the collarbone, and in the chest behind the breastbone.

Cancer cells break away from where the tumor is. These cells then go into your blood vessels or lymph vessels. From there they can enter all tissues of your body. As they travel, cancer cells can attach to other tissues and grow to form new tumors.

This spread is called metastasis.

Breast Carcinomas

Breast cancer is almost always a type of carcinoma, because breast cancer often starts in the lining of the breast. Breast cancer can be either a ductal carcinoma or a lobular carcinoma.

Carcinomas are treated based on whether or not they are invasive, or have spread into tissues near the cancer cells. There are two types of non-invasive carcinomas of the breast:

  • ductal carcinoma in situ (meaning the cancer cells are in the breast ducts) or
  • lobular carcinoma in situ (meaning the cancer cells are in the breast lobules).

Carcinoma in situ means it is an early stage of cancer and is usually very treatable. The cancerous cells are contained; they have not spread deeper in the breast and they have not spread to other organs in your body.

Since these types of carcinoma in situ have not spread, they are also called non-invasive or pre-invasive breast cancers.

There are two types of invasive carcinomas:

  • invasive ductal carcinoma (in the ducts) or
  • invasive lobular carcinoma (in the lobules)

Some breast cancers start in tissue of the glands. A gland is a tissue that produces a substance. Your breast’s ducts and lobules are gland tissues, as they make breast milk. Cancers that start in these gland tissues are called adenocarcinomas.

With Your Healthcare Team

When going through cancer treatment, your healthcare team is very important. Your healthcare team may include your oncologists, surgeon, nurse navigator, a dietitian, a social worker, or other medical professionals. Every member plays an important role. Use the tips below for talking with your healthcare team:

  • Establish your main point of contact.
  • Your main point of contact will probably be a nurse navigator, but it may be another member of your healthcare team. Who should you contact first with questions?
  • You need to always be open and honest with your healthcare team about your physical and emotional well-being.
  • Do not be afraid to ask questions.
  • Breast cancer is usually not a medical emergency. There is time to ask your healthcare team any questions you may have, and to consider your treatment options.
  • Write your questions down before your appointments. Take a pen and paper to write down the answers
  • Before beginning treatment, ask your healthcare team the following:
  • What are all my treatment options?
  • What are the long term and short term side effects of treatment, and how can I manage them?
  • Will my fertility or ability to have children be affected?
  • Am I eligible for clinical trials?
  • If you develop any new problems or symptoms during treatment, tell your healthcare team immediately. You are not complaining. This is valuable information for your doctors.
  • Do not change your diet, start an exercise program, or take any new medications, including vitamins and supplements, during treatment without talking to your healthcare team first.

With Your Caregiver

Your primary caregiver may be with you when you receive your diagnosis. Your primary caregiver may be your spouse, partner, adult child, parent, or friend. Your primary caregiver is the person who may come with you to appointments, take care of you after surgery or treatment, and support you throughout your cancer journey.

  • Everyone reacts to the news of cancer differently. You may feel upset, shocked, or angry. It may take you some time to process the information. Your caregiver may react the same way you do, or your caregiver may not. Even if your caregiver does not react the same way you do, it does not mean that he or she does not care deeply.
  • Establish your role and your caregiver’s role early. For example, will your caregiver be the one scheduling most of your appointments, or do you prefer to take an active role? Find what works best for you and your caregiver.
  • Be open and honest with each other about how you both feel. Overly positive attitudes may hinder honest communication. It’s okay to be upset.
  • Encourage your caregiver to take time to care for his or her own physical and emotional well-being. Being a caregiver comes with its own hardships.
  • If your primary caregiver is your spouse or partner, your intimate and physical relationship may change.

With Your Children

Children are very perceptive, no matter their age. While you may wish to protect your children by not telling them about your diagnosis, even young children may be able to tell that something is wrong. Not knowing what is wrong may cause them more stress and anxiety. Here are some tips to talk to your children and teens about your cancer diagnosis:

  • Wait until your emotions are under control and decide what to say ahead of time.
  • Tell the truth and answer questions honestly. Depending on your children’s ages, it may not be appropriate to give them all the details, but do be truthful.
  • Let them know what to expect. For example, let them know that after surgery you will need a lot of rest and may need to stay in the hospital. If your chemotherapy may cause you to lose your hair, let them know. Keep your children in the loop as much as possible.
  • Explain to your children, especially younger children, that they cannot “catch” cancer.
  • Let your children know that it is okay to cry or be upset. This may be especially important for your teens to hear.
  • Tell teachers, babysitters, and others with responsibilities with and around your kids about your diagnosis in case they see behavior changes you may need to know about.
  • Maintain normal schedules as much as possible.
  • Let your kids help. Allow them to help with chores, and let them know that their help is important. Teens may want to take an active caregiver role. Let them do so, at appropriate levels.
  • Look for support groups in your area. Many places offer support groups for children and teens whose parents have a cancer diagnosis.
  • Know when to seek professional help. If your child begins to demonstrate unusual behavior such as angry outbursts, nightmares, or poor grades in school, ask your healthcare team for a recommendation for a counselor.

With Family and Friends

You may choose to keep your cancer journey private, or you may choose to share your story with others. The choice is yours. Remember when family, friends, coworkers, or other acquaintances ask about your diagnosis, they are genuinely concerned about your well-being. You can share with them as much or as little information as you like. These suggestions may help you talk about your diagnosis:

  • Decide how much information you want to share before you start telling people about your diagnosis.
  • If you chose to keep your journey private, make sure to let people know that you appreciate their concern, but you hope they respect your privacy.
  • Choose someone close to you, like your caregiver, to spread the word about updates and treatment progress. After a long day of treatment, you may not feel like calling and texting people, but your friends and family will probably want to know how you are.
  • If you want to share your story, consider starting an email chain or a Facebook group.

This way you can update everyone with one message instead of needing to answer a lot of emails and phone calls.

  • You can also create your own private website at MyLifeLine.org.
  • When people offer to help with things, let them. Your family and friends could cook dinner, drive you to an appointment, or babysit.
  • If you lose your hair due to treatment or have visible surgical scars, strangers may ask about your diagnosis. Have a response prepared. Again, you may share as little or as much as you like.

An important part of breast cancer diagnosis is determining whether the breast tumor has a receptor for either estrogen, progesterone, or both and if the breast tumor is HER2/neu positive.

To understand why this is important, you need to know how the hormones work in your body. Every female has estrogen and progesterone hormones. These hormones travel through your bloodstream. They stimulate both cell division and the growth of new cells.

Estrogen receptors (ER) and progesterone receptors (PR) are proteins found in certain cells. These receptors attach to estrogen and progesterone.

Many breast tumors have these receptors. Often they have a lot of them. This means the tumors are hormone-dependent. The hormones estrogen and progesterone cause them to grow.

An early step in the diagnosis process is to test the cancerous tissue to see if it is:

HER2/neu positive: Human epidermal growth factor receptor two is a protein sometimes involved in breast cancer. Too much of the protein on the surface of cancer cells indicates increased aggressiveness.

Estrogen receptor positive: the tumor has estrogen receptors and needs estrogen to grow. An effective treatment strategy may be treating the cancer cells with hormones that block estrogen.

Progesterone receptor positive: the tumor has progesterone receptors and needs progesterone to grow. An effective treatment strategy may be treating the cancer cells with hormones that block progesterone.

Tumors that are progesterone receptor positive or estrogen receptor positive are more likely to respond to therapy. Outcomes are often better.

About the Progesterone Receptor and Estrogen Receptor Tests

As explained above, these lab tests determine whether the cancer cells have receptors for either progesterone or estrogen. The first step in taking this test involves getting a sample of the cancer tissue. This can be done through a:

  • Fine needle aspiration
  • Needle biopsy
  • Surgical biopsy

Another type of breast cancer:

Inflammatory breast cancer is a rare type of breast cancer. In this type, cancer cells block the lymph vessels in the skin of your breast. The breast ends up looking red and swollen. Inflammatory breast cancer is always at least Stage 3B, but it could be more advanced.

What is genetic counseling?

Genetic counseling helps people determine their risk for hereditary cancers. Genetic counselors are medical specialists who help people do the following:

  • identify their risk for hereditary forms of cancer and
  • develop a personalized plan to manage risk.

What happens during genetic counseling?

First, you will provide your family medical history. From the history, your genetic counselor determines the likelihood that cancer in your family is hereditary. Your genetic counselor will discuss with you the following:

  • your need for genetic testing
  • any inheritance patterns in your family
  • your surveillance and risk reduction options

If you choose to do testing, your genetic counselor will coordinate the testing. After testing, your genetic counselor will interpret the results for you to come up with the best surveillance and risk reduction plan for you. Your genetic counselor will also tell you if other members of your family need to be tested.

What are the most common hereditary cancer syndromes?

Genetic testing for hereditary breast and ovarian cancer and Lynch syndrome are the most common reasons for referrals to genetic counselors.

What are BRCA mutations?

The BRCA1 and BRCA2 gene mutations make up the majority of hereditary breast and ovarian cancers.

Women who carry mutations in the BRCA genes have a 55-85% risk of developing breast cancer and a 15-60% risk of developing ovarian cancer. For women who do not carry mutations in the BRCA genes, the risk is 12-13% for breast cancer and 1-2% for ovarian cancer. Men who carry mutations in the BRCA genes have a slightly increased risk for prostate cancer. Men who carry BRAC2 mutations have an increased risk for male breast cancer, pancreatic cancer, and perhaps melanoma.

Should I do genetic testing?

If one or more of these apply to you, talk to your healthcare team about genetic testing.

  • Multiple family members on the same side of the family with the same cancer
  • Multiple family members on the same side of the family with related cancers (breast/ovarian/pancreatic or colon/uterine/ovarian)
  • Cancer at early ages  (under 50)
  • More than one diagnosis of cancer in the same person
  • Rare cancers
  • A known family history of altered genes that increase cancer risk
  • Triple negative breast cancer diagnosis before 60
  • Jewish ancestry
  • A personal or family history of breast, ovarian, or pancreatic cancer
  • If you have a pheochromocytoma or a paraganglioma tumor

If you are concerned about hereditary cancers, speak to your healthcare team or find a genetic counselor.

Where can I find a genetic counselor?

You can find a genetic counselor using the National Society of Genetic Counselors website at www.nsgc.org. You can also ask your healthcare team for a referral.

Will my insurance cover genetic testing?

Most insurance companies now cover genetic testing for people with a family history that suggests a hereditary cancer syndrome. Your genetic counselor can help you verify your coverage.

If you are uninsured or genetic testing is not covered by your insurance, your genetic counselor can help you locate local and national resources.

I’ve decided to meet with a genetic counselor. How should I prepare?

You need to give your genetic counselor as much accurate and detailed information as possible. Your genetic counselor will want to know about:

  • Your personal and/or family history of cancer
  • Who was diagnosed? Which side of the family?
  • What was the diagnosis?
  • What was his or her age at diagnosis?
  • Pathology reports
  • Death certificates
  • Age and cause of death of all family members
  • Your ethnic background
  • Any Jewish ancestry

Even if you have little or no information about your family history, you can still speak with a genetic counselor.

I tested positive for a hereditary cancer syndrome. Now what do I do?

Your genetic counselor will help you come up with the best surveillance and risk reduction plan based on your risk. You may be referred to a doctor who can advise you about how to prevent the cancer identified, sometimes through surgery to remove the organ that could develop cancer. Be sure always follow your recommended screening schedule. Cancer is easier to treat when caught early.

Your genetic counselor can help you share your test results and coordinate testing for family members. Your family needs to know about surveillance and risk reduction options. Some family members may not carry the same mutation.

The TNM staging system is used for all types of cancer, not just breast cancer. The letters TNM describe the amount and spread of cancer in your body:

  • T: indicates how big the tumor is and whether the cancer has spread into surrounding tissue.
  • N: indicates whether the cancer has spread to surrounding lymph nodes.
  • M: indicates metastasis, which means that cancer has spread to other body parts. Using TNM, your doctor will diagnose your cancer according to one of the following stages:

Stage 0

This is an extremely early stage. Abnormal cells are

present. For example, there may be abnormal cells in the lining of a breast duct (ductal carcinoma in situ) but there has been no spread.

Stage 1

This is a very early stage. Cancer cells are in the breast tissue but have not spread beyond the breast. The tumor is not more than 2 centimeters across.

Stage 2

Breast cancer is called Stage 2 when either:

  • The tumor is no more than 2 cm. in size but has spread to the lymph nodes under the arm.
  • The tumor is between 2 cm. and 5 cm. but has not spread.
  • The tumor is between 2 cm. and 5 cm. and has spread.
  • The tumor is over 5 cm. but has not spread.

Stage 3

This stage is called locally advanced cancer. The cancer has spread from where it began into nearby tissue and lymph nodes. Stage 3 is divided into 3 types: A, B and C.

Stage 3A

Stage 3A refers to breast cancer in which the tumor has spread to lymph nodes under your arm. It’s also possible for the cancer to have spread to lymph nodes behind your breastbone. The tumor can be either:

  • Not over 5 cm.
  • More than 5 cm.

Stage 3B

This stage refers to any size tumor that has grown into the chest wall or breast skin. It can be accompanied by breast swelling and nodules (lumps) in the skin on your breast. Also in this stage the cancer may have spread to lymph nodes under the arm, or to lymph nodes behind the breastbone.

Stage 3C

This stage refers to a tumor of any size. It has spread either:

  • To the lymph nodes behind the breastbone and under the arm.
  • To the lymph nodes above or below the collarbone.

Stage 4

This stage refers to a tumor of any size that has spread to other parts or areas of the body beyond the breast and nearby lymph nodes. These areas may include lungs, distant lymph nodes, bones, or brain.

Abnormal cells: cells that do not look or behave like healthy cells Aggressive: fast growing

Benign: not cancerous

Biopsy: a procedure to take a small sample of tissue

Clean/ clear/ negative margins: the outer edge of the tissue sample does not contain cancer cells

Ductal Carcinoma In Situ (DCIS): cancer cells in the milk duct that have not invaded surrounding tissue

ER-negative: the tumor does not have estrogen receptors.

ER-positive: the tumor has estrogen receptors and needs estrogen to grow.

Florescence In Situ Hybridization (FISH): a test used to find genetic mutations

Grade: how abnormal the cells look and how quickly the tumor is likely to grow. There are three grades for cancer cells. Grade 1 (low grade) means the cancer cells are only a little different from healthy cells and are slow-growing. Grade 2 (high grade) means the cells look very different from healthy cells and are fast-growing.

HER2: Human epidermal growth factor receptor two is a protein sometimes involved in breast cancer. Too much of the protein on the surface of cancer cells indicates increased aggressiveness.

Histology: the way the cells look under a microscope

Inconclusive: with the current sample and tests, it cannot be determined if cancer is present

Invasive: the cancer has spread to surrounding tissues

Invasive Ductal Carcinoma (IDC): cancer cells in the milk duct that have invaded surrounding tissue

Invasive Lobular Carcinoma (ILC): cancer cells in the milk lobules that have invaded surrounding tissue

In Situ: abnormal cells have not spread; the abnormal cells are only where they started

Lobular Carcinoma In Situ (LCIS): cancer cells in the milk lobules that have not invaded surrounding tissue

Lymph node: lymph nodes filter lymphatic fluid and store white blood cells.

Malignant: cancerous

Metastasis: cancer that has spread to other parts of the body

Pathologist: a doctor who identifies diseases by studying cells and tissues under a microscope

Positive margins: the outer edge of the tissue sample does contain cancer cells

PR-negative: the tumor does not have progesterone receptors.

PR-positive: the tumor has progesterone receptors and needs progesterone to grow.

Stage: how advanced the cancer is

Stains: used to color the tissues and cells so the pathologist can see them better

Tissue Block: the sample of tissue removed during a biopsy or surgery

Vascular invasion: cancer cells are in the blood vessels

How Breast Cancer Spreads

Before you can understand how breast cancer cells can spread, it's important to have a clear picture of the anatomy of your breasts.

Breast Cancer Diagram