The Breasts and Lymphatic System

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The breasts

The breasts are made up of:

  • Fat
  • Connective tissue
  • Gland tissue divided into lobes

A network of ducts spreads from the lobes towards the nipple.

Breast size and density

It is very common for breasts to be different sizes from one another. They may also feel different at different times of the month – for example, just before a period they can feel lumpy.

Breast density changes as a woman ages. Younger women have more glandular tissue in their breasts, which makes them dense. Once a woman goes through menopause, the glandular tissue is gradually replaced by fat, which is less dense. It is more difficult to read a mammogram if the breast tissue is dense so mammograms are not as reliable for younger women.

Specialists have found that older women who take hormone replacement therapy (HRT) have denser breasts than would be expected for their age, which can make their mammograms less accurate.

Most women are aware of the common risk factors when it comes to breast cancer. However, many are not aware of the importance of breast density, which has been described as one of the most significant risk factors of all. Women with dense breasts have a higher proportion of fibroglandular and supportive tissue, whereas those with less dense breasts have a higher proportion of fat.

Unfortunately, breast density cannot be measured by look or feel, only by mammography, where dense breast tissue appears white and fatty breast tissue appears dark.

Breast density can be categorised into:

  • Mostly fatty – accounts for less than 10% of women in Ireland
  • Scattered density – accounts for about 40% of women
  • Heterogeneously dense less than 40% of women and
  • Extremely dense less than 10% of women

Breast density is one of the strongest independent risk-factors for developing breast cancer, stronger even than age or family history, with women with ‘extremely dense’ breast tissue being four-to-six times more likely to develop breast cancer compared to women with ‘mostly fatty’ breasts. High breast density can also have the effect of ‘masking’ breast cancers, as they also show up as white on a mammogram, and are thus more difficult to see.

Breast density cannot be measured by look or feel, only by mammography, where dense breast tissue appears white and fatty breast tissue appears dark.

10% of women between the ages of 40 – 74 have extremely dense breast, 35% have heterogeneously dense breast. These are the women who are at risk of a cancer not being picked up by mammogram as dense breast look white on a mammogram and cancer looks white on a mammogram.

Currently, women in Ireland going through the BreastCheck mammographic screening programme are not routinely informed about their breast density when receiving their results, and many are unaware of this important risk-factor.

For more information on breast density, please see:

Lymph nodes and the lymphatic system

Our bodies have a network of lymph vessels and lymph nodes which is part of the body’s immune system. It collects fluid, waste material, and other things such as viruses and bacteria that are in the body tissues, outside the bloodstream.

In the same way that veins collect and carry blood through the body, lymph vessels carry a watery yellow fluid called lymph. Lymph flows through the lymphatic system and eventually drains into veins. This system helps to get rid of waste products from the body.

Lymph nodes are important in cancer care because any cancer cells that have broken away from a cancerous tumour can be carried by the tissue fluid to the nearest lymph nodes. If your doctors finds a cancerous tumour, they will always examine your lymph nodes to see if there are cancer cells present there. If there are no cancer cells in the nearby lymph glands, your cancer is less likely to have spread. Sometimes lymph nodes become enlarged for other reasons that are not related to cancer e.g. infection.

Your breast tissue extends to under your armpit. The armpits have many lymph nodes, also known as lymph glands. There is also a chain of lymph nodes that runs up the center of your chest, by your breast bone. This is called the internal mammary chain. The diagram shows the network of lymph nodes around the breast.   Because your breast tissue extends to your collar bone and your armpit, it is important to check these areas during your monthly breast self-examination.

Breast Cancer Information

Some useful Breast Cancer resources…

01

What You Should Know

A summary of the signs and symptoms, advice on how to check your breasts and an overview on how breast cancer is diagnosed and treated.

Learn more
02

Risk Factor

Read about the factors that can increase or reduce your risk of breast cancer.

Learn more
03

Symptoms

Information on the signs and symptoms of breast cancer, how to check your breasts and what to do if you find something.

Learn more
04

Prevention

We can take steps to reduce our breast cancer risk.

Learn more
05

How To Check Your Breasts

Find out what to look and feel for.

Learn more
06

Diagnosing Breast Cancer

Find out about seeing your GP, referral to a specialist and tests you might have.

Learn more
07

Your Breasts

Find out about the structure of the breasts and about the lymphatic glands.

Learn more
08

Inflammatory Breast Cancer

This page has information about diagnosis, treatment and side effects.

Learn more

Check Monthly

One week after the end of your period is the best time. If you have reached the menopause, check your breasts on the same day every month.

Look For Changes

Stand in front of a mirror with your hands in the air. Look for changes in size or shape, puckering, dimpling or redness of the skin.

Feel For Changes

Using your fingers, check for any lumps, thickening or bumps.

Areas Not To Forget

Gently squeeze the nipple to check for discharge. Check your armpit as breast tissue also extends here.

Talking

Breast Cancer

This season we are talking about breast cancer. Helen Forristal, Director of Nursing services at the Marie Keating Foundation hosts this informative and impactful 5-episode patient-led series.
This season focuses on open and honest discussions with two groups of women. Three women living with Metastatic breast cancer and two women Surviving and thriving after localized breast cancer. These women share valuable insights from their unique experiences at every step of their journey. They share what they wish they knew and what they want others to know that may be hugely supportive to anyone newly diagnosed.
This season we are letting the patient voice take the lead. Season 4 is for patients by patients.
With thanks to our co-sponsors…
Season 4

Talking Breast Cancer

Here’s a sneak peek at what to expect from this series of The Marie Keating Foundation Talks Breast Cancer!

Season 4

Episode 1: Breast Cancer in Ireland

Talking Breast Cancer Season 4 Episode 1 : Breast Cancer in Ireland

This series we are talking Breast Cancer and letting the patient voice take the lead. Season 4 is for patients, by patients. We are kicking it off in episode one by setting the foundations of Breast Cancer in Ireland.

In this episode Director of Nursing, Helen Forristal talks to CNS, Niamh Byrne and ANP, Carol Spillane from The St James Hospital Breast care clinic.

The topics covered include, Facts, stats and background to Breast Cancer in Ireland. Signs and Symptoms, when to go to your GP, Family History, Influence of Covid and so much more valuable information.

Season 4

Episode 2: A discussion with two women about living with and beyond a Localised Breast Cancer Diagnosis

From here onwards we let the patient voices take the lead.

In this episode we talk to Erica Tierney and Paula Gleeson from The Marie Keating Foundation Survive and Thrive community about living with and beyond a localised breast cancer diagnosis.

This episode covers a wide range of valuable information that stems from the lived experiences of these women.

We discuss, at diagnosis what would they like women or men to know that they did not know back then?
Treatments, the benefits versus risks, family history, choices, trauma, follow up, support services and so much more.

Season 4

Episode 3: Living with Metastatic Breast Cancer

In this episode we have the privilege of talking to three women from The Marie Keating Foundation Positive Living Community, Aine Murphy, Deirdre Digan and Lisa Dowling. These women will take us through their unique experiences living with metastatic breast cancer and want the listeners to understand what it means to have an incurable cancer. They will also enlighten us on what they would like women and men to know that they did not know.

They will talk us through diagnosis, treatment, risks, family history, communication, clinical trials, counselling, palliative care, nutrition, and exercise, going back to work and so much more in this incredibly impactful conversation.

Season 4

Episode 4, Part 1: Survivorship and Living with and Beyond Cancer

We have reached the final episode of this series There is so much valuable information in this episode that we have made it a 2 Part.

What a journey we have been on discussing every step of a breast cancer journey. In these episodes we are continuing with the patient voice as we discuss survivorship, living with and beyond cancer and how the women we spoke to in this series have learned to live their best lives despite cancer.

Each offers valuable insight and advice from their own unique experience culminating in conversations packed with information for anyone facing a similar journey or those with family, friends or work colleagues facing a breast cancer journey. These episodes cover topics like returning to work, need for public education, chemotherapy, symptom tracking, such as fatigue, pain, peripheral Neuropathy. We discuss weight loss and gain, sexual function, menopause, depression, hair loss, trauma and so much more.

They will talk us through diagnosis, treatment, risks, family history, communication, clinical trials, counselling, palliative care, nutrition, and exercise, going back to work and so much more in this incredibly impactful conversation.

Season 4

Episode 4, Part 2: Survivorship and Living with and Beyond Cancer

A continuation of the important conversations started in Part 1.

How to reduce your risk of breast cancer

Learn more about how you can reduce your risk of breast cancer.

Be a healthy weight

Being overweight or obese after menopause increases the risk of breast cancer. If you are overweight, try to reduce your intake of sugary and processed foods and eat more fruit and vegetables.

Limit alcohol

Research consistently shows that drinking alcohol increases your risk of breast cancer. The more alcohol you drink, the greater your risk. Women are recommended to have 11 units or less of alcohol a week, and no more than 2 units a day. Try to have days where you consume no alcohol at all. If you have been diagnosed with breast cancer you should consider giving up alcohol.

Get active

Most studies indicate that physically active women have a lower risk of developing breast cancer than inactive women. The more often and longer you exercise, the less your risk of developing breast cancer. Aim for 30 to 60 minutes per day of moderate- to high-intensity physical activity.

Breast feed

Breastfeeding lowers the risk of breast cancer, especially in premenopausal women. Mothers who breastfeed for a total of one year over the total of their lifetime are slightly less likely to get breast cancer than those who have never breastfed.

Check Your Breasts

Unfortunately there is little we can do about some risks associated with breast cancer apart from being aware of them. But you can be aware of breast changes to look out for.  It is important to attend for breast screening tests with BreastCheck when you are invited. You should also check your breasts once a month, looking and feeling for any changes.

Don’t smoke

Smoking is linked to a higher risk of breast cancer in younger, pre-menopausal women. Research has also shown that there may be a link between very heavy second-hand smoke exposure and breast cancer risk in post-menopausal women.

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