New tool helps detect lymphedema, a fluid buildup

Host Amber Smith: Upstate Medical University in Syracuse, New York invites you to be "The Informed Patient" with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith. A quarter to a third of breast cancer patients may develop lymphedema over their lifespan. We'll learn more about that and a new tool that helps health care providers detect lymphedema as early as possible from Lauren Buck. She's a doctor of physical therapy at Upstate and a certified lymphedema specialist. Welcome to "The Informed Patient", Dr. Buck.

Lauren Buck, DPT: Thank you, Amber. Thanks for having me.

Host Amber Smith: Let's start with a description of what lymphedema is. I know edema means swelling, right?

Lauren Buck, DPT: Yeah, you're right Amber. Edema does mean swelling, but it can also be described as kind of a buildup of fluid anywhere in the body's tissues. And lymph refers to the fluid circulating in the lymphatic system. So together, lymphedema really refers to a buildup of lymph fluid somewhere in the body's tissues. And lymphedema specifically is an accumulation of protein-rich fluid in an area of the body.

Host Amber Smith: So this protein-rich fluid, why do we need it?

Lauren Buck, DPT: So the protein-rich fluid is really a byproduct of our vascular system. It's found initially within our, inbetween the tissue, the cell tissues. Not only does lymph fluid contain large proteins, but the fluid entering the lymphatic system also contains cellular waste, bacteria, viruses, and also circulating foreign particles. The lymphatic system is really the only system in the body that is anatomically designed to absorb these macromolecules.

Host Amber Smith: How does the body get rid of the waste that's in the fluid?

Lauren Buck, DPT: To explain how and why the body produces fluid, I kind of need to tell you a little bit about the role of the lymphatic system and the anatomy of the microcirculation so you can get kind of a better understanding or appreciation how it all works.

So the lymphatic system can be basically thought of as our fluid recycling system. It absorbs and transports fluid from the body's tissues to maintain a fluid balance. So lymph fluid enters the lymphatic system through the interstitial lymphatic vessels, which are found within the tissue spaces between our cells. Also within these tissue spaces are the capillary beds, which are the smallest blood vessels in the body.

The capillary beds is where arteries and veins connect, and this area of blood exchange is referred to as our microcirculation. So at this level of the microcirculation, oxygenated blood is sent to our tissues to help supply them with nutrients and also to pick up waste products. Because of pressure differences, some of the fluid kind of flows out of the arteries into this microcirculation, and this is where that lymphatic system comes into play.

The lymphatic system helps absorb that excess fluid underneath the surface of the skin in those interstitial spaces. When there's an abundance of this fluid, the lymphatic system is stressed, and it opens up these channels and allows the fluid to flow into the lymph system. The lymphatic system then kind of transports this fluid from the area of absorption to the level of the heart and returns it back into the venous system, or circulatory system.

Are all of the lymph nodes in our body connected to the lymphatic system? For lymph nodes, they're connected intricately in a network all over our body. So if you think of like a kind of a spider web network, we have lymphatic vessels all over our body, and they are technically connected.So the lymph nodes are connected by varying lymphatic vessels. And they work in concert with our venous system or circulatory system to help filter that fluid and bring it back toward our heart.

Host Amber Smith: Now, what causes lymphedema, and how soon after cancer treatment is this likely to occur?

Lauren Buck, DPT: Lymphedema typically occurs because of some level of obstruction to the lymphatic system that will slow or congest the fluid within the system.

We can classify lymphedema as primary or secondary. So our primary lymphedemas are something that are typically present at birth due to a malformation of some portion of the lymphatic system. And our secondary lymphedema is lymphedema that occurs because of some other disease process.

The No. 1 cause of lymphedema worldwide is actually filariasis, which filariasis is like a parasite born infection where the parasite infiltrates the lymphatic system and causes irreversible damage.

In the U.S., though, cancer and cancer related treatments are the main cause of dysfunction to the lymphatic system, which may result in lymphedema. So treatments for cancer, such as like lymph node dissection, radiation therapy, the impacts from chemotherapy. They're not necessarily the cause of lymphedema, but they result in an overall functional loss of the system in the area that's affected.

We also have like other secondary causes of lymphedema, such as chronic venous insufficiency, trauma to an extremity, surgery, obesity and infection.

Host Amber Smith: This is Upstate's "The Informed Patient" podcast. I'm your host, Amber Smith. I'm talking with physical therapist and certified lymphedema specialist Lauren Buck.

Are we able to predict which patients are at greater risk for lymphedema?

Lauren Buck, DPT: We are able to have some prediction about who is at a greater risk for lymphedema. We typically use a risk stratification system, so we have some criteria that we look at. We categorize our patients into a low risk category for lymphedema, medium risk and high risk.

And some of the criteria we look at is what type of lymph node surgery they had, whether it was a sentinel lymph node biopsy. And what that is, is when there's a small number of lymph nodes removed -- anywhere from usually like one to three nodes -- versus an axillary dissection, which is usually a larger node sampling of an area.

Patients that have an axillary lymph node dissection, or that larger number of nodes, are at a higher risk. There is some correlation as well with BMI, and a greater BMI places an individual at higher risk for developing lymphedema. And alsothe area of radiation -- if the local lymph nodes are radiated, or what we call as regional lymph node radiation, then the patient is at slightly greater or higher risk.

Host Amber Smith: And BMI being the body mass index?

Lauren Buck, DPT: Correct. Yes.

Host Amber Smith: So can you tell us about the new machine at the Upstate Cancer Center that's used with lymphedema?

Lauren Buck, DPT: Our new machine that we have is called the SOZO Digital (Health) Platform. The SOZO is a bioimpedance machine. And what that does, and what it tells us is basically fluid levels in the body. And what we specifically look at when we are taking these initial measurements on patients is a fluid comparison measurement from an extremity that is at risk for lymphedema and their other extremity.

Host Amber Smith: Is it always a lymphedema in the extremities, in the arms and legs?

Lauren Buck, DPT: No, actually, lymphedema can occur really in any of the body's tissues. But in our oncology population, certain areas of the body may be more susceptible due to the location of the cancer and / or the treatment focus. With our breast cancer population, lymphedema risk is highest in the arm on the same side that the cancer was found. And it's not just in the extremity. It also can be in the breast or chest area, the lateral trunk or the side of the body, and the upper back.

Host Amber Smith: So could somebody have like a fluid buildup that they are unaware of, that this machine is able to pick up on?

Lauren Buck, DPT: Absolutely. The machine is reliable and valid and can detect even the smallest fluid shift changes. It advertises that it can detect fluid changes as low as 36 milliliters, which is pretty minute. We utilize it to kind of overall see a pattern and see: Are the fluid levels changing in this patient, in their extremity that is at risk for lymphedema.

Host Amber Smith: Can you walk us through how the test is done from the patient's point of view? How long does it take?

Lauren Buck, DPT: The test is fairly simple and easy for the patient. They just remove their socks and shoes. They typically stand on the device. It's like a bathroom scale, and their hands get in contact with the surface and their feet. It takes about 20 to 30 seconds. And during that timeframe, it is passing a painless, harmless, electrical occurrence through the body, different frequencies. And some of these frequencies pass through the cells. Some go around the cells. And it does a calculation that does a comparison of how much fluid is left outside of the cells.

That's what we equate to, or we call, swelling, per se. So the measurement, like I said, that we typically look at the most in these baseline assessments is our L-dex measurement, and that is that comparison from one arm to the other.

Host Amber Smith: If the measurement does show a troubling amount of fluid buildup, what then? I mean, how is lymphedema treated?

Lauren Buck, DPT: If we see that the measurement increases above a specific threshold, then the likelihood of a subclinical lymphedema is high. So in these cases, we can intervene with specific exercises. We can provide compression garments and then we'll retest the measurement in about a month. We usually prescribe compression to be utilized for all daytime hours if the patient develops fluid levels above that threshold that we look at.

So if the value has remained at the same level or it's increased when we retest the value, then we'll continue with compression and add in other components of lymphedema therapy. So, as a lymphedema therapist, we utilize what we call complete decongestive therapy. And this is really just a series of interventions or techniques. So we utilize massage techniques, which we call manual lymphatic drainage. We provide skin care recommendations, exercise prescription and compression garment recommendations for the patient. And that's really the gold standard of treatment for lymphedema.

Host Amber Smith: Do people with lymphedema have to restrict their diet or their activities?

Lauren Buck, DPT: So generally speaking, we typically recommend a diet that is low inflammatory foods, low sugar, low salt, the typical eat your fruits and veggies and get enough protein. Try to limit the processed foods because as you know, sometimes that can increase inflammatory cells in our body. As far as activity modification, that's really patient dependent. And that's where our education comes into play because we basically need to teach the patient about their threshold for activity, like how much activity can they do without putting too much stress on their lymphatic system?

So we tend to educate, if you experience any heaviness, achiness, fatigue, numbness, tingling, those are our main descriptors to say, there might be an activity that caused that for them. Say they did some heavy lifting at their job that day, and then they experience those symptoms. Then we would say, you know, you might need to back off of that activity a little bit in order to have those symptoms recede.

So we do teach some activity modification, but it's really patient dependent, and it depends, like I said, on their anatomy and how they react to the dysfunction that's happened in their lymphatic system.

Host Amber Smith: Well I want to thank you for making time for this interview, Dr. Buck. I appreciate it.

Lauren Buck, DPT: Yeah. Thank you very much for having me.

Host Amber Smith: My guest has been Lauren Buck, a doctor of physical therapy and a certified lymphedema specialist at Upstate. "The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe with sound engineering by Bill Broeckel, and graphic design by Dan Cameron. Find our archive of previous episodes at upstate.edu/informed. If you enjoyed this episode, please invite a friend to listen. You can also rate and review "The Informed Patient" podcast on Spotify, Apple Podcasts, YouTube, or wherever you tune in. This is your host, Amber Smith, thanking you for listening.