“Stimulating lymphatic drainage is crucial”

Last fall , Professor Peter Mortimer was honored with the Ratschow Memorial Medal for his commitment to lymphology. Bauerfeind life talked to the Brit , who works as a dermatologist at St George’s, University of London, about the causes of lymphedema and how it can be treated.

You are conducting groundbreaking research into the lymphatic system and hereditary lymphedema. What is it about this work that fascinates you?

Prof. Mortimer: I have been interested in the lymphatic system after I realized in the early 1980s that it was such a neglected area of medicine. I started investigating breast cancer related lymphedema but became more interested in primary (genetic) lymphedema when the first genes controlling lymphatic system development were discovered. My clinic receives children and young adults with lymphedema from all over the UK. The study of the DNA from families with similar lymphedema enabled causal genes to be found. We can now identify a gene cause in 20 percent of the patients we see with primary lymphedema. The importance of finding genes it that it helps us understand the mechanism for the lymphedema and with that information we have much more chance of developing a specific treatment.

“As the lymph system requires movement to promote drainage,
and in the absence of any drug treatment to achieve this, exercise must be the first aspect of treatment.”
Prof. Peter Mortimer

Is there anything else in this field that you’d like to research?

Prof. Mortimer: One of the biggest challenges in managing patients with lymphedema is the attacks of infection with which they suffer, particularly cellulitis (erysipelas). Attacks of cellulitis are often recurrent and so patients are seeing their family doctor frequently. Sometimes the attacks of infection make the patient so sick with sepsis they suffer organ failure. Because the lymphatic system houses our immune system it is probably a failure of localized immunity within the lymphedema swelling that creates this problem and so infection is never properly eradicated. I would like to understand more about the mechanism for these events.

What differences are there, if any, between lymphedema in the upper body and lymphedema in the legs?

Prof. Mortimer: Lymphedema of the legs is more common, and often worse, than in the upper limb. This is often attributed to the effects of gravity. While that may be true there may be other reasons for the legs being more commonly involved. In a genetic form of congenital lymphedema called Milroy disease, the mutation in VEGFR3 causes hindlimb not forelimb lymphedema, suggesting genetic factors may determine sites affected by lymphedema. Indeed, leg swelling is generally more common in primary lymphedema than upper limb swelling. Arm swelling would be quite rare if not for breast cancer related lymphedema.

Has the number of edemas been reduced by minimally invasive surgical techniques?

Prof. Mortimer: The introduction of sentinel lymph node biopsy (SLNB) was intended to reduce the incidence of lymphedema and in principle it has. The prevalence of arm lymphedema after a full axillary dissection for breast cancer treatment is approximately 20 percent whereas after SLNB it is around six percent. However, the necessary additional oncology adjuvant treatments accompanying SLNB such as radiation and taxane chemotherapy push the prevalence higher.

“Compression garments must be well fitted and comfortable for the patient to wear.”
Prof. Peter Mortimer

In general , how have upper-body edemas changed for patients over time?

Prof. Mortimer: If breast cancer treatment is used as an example, then in the days of the old-fashioned mastectomy there was high incidence of arm lymphedema but no breast or chest wall lymphedema. Now with wide local excisions of breast tumors accompanied by breast radiation, lymphedema of the remaining breast may be as common, if not more so, than arm lymphedema.

What would you say are the essential factors when treating lymphedema?

Prof. Mortimer: The essential factors in treating lymphedema are to stimulate improved lymph drainage by physical means. As the lymph system requires movement to promote drainage, and in the absence of any drug treatment to achieve this, exercise must be the first aspect of treatment. Compression, by enhancing the effect of muscle contractions on lymph drainage, accompanies the exercise where possible.
It is also important to find out if there is a treatable cause. For example, in some lymphedema, it is necessary to treat the underlying inflammation first before embarking on standard treatment.

What needs to be considered when it comes to compression therapy?

Prof. Mortimer: Compression is designed to complement the effect of movement. Oscillating changes in tissue pressure is what makes lymph vessels fill and empty. Compression provides greater changes in tissue pressure during movement to drive greater lymph flow. Effective compression needs to conform to the size and shape of the swollen tissues to be treated. Compression garments need to ‘contain’ the swelling and not stretch unnecessarily. That means once on they should not ‘give in’. Compression must not obstruct lymph drainage. Therefore, compression garments must be well fitted and comfortable for the patient to wear.

Images: Bauerfeind