Contemporary concepts in lymphatic surgery. A little old and a whole lot of new.

Contemporary concepts in lymphatic surgery

A little old and a whole lot new

By James Kennedy

Asreaders of this magazine will already know, decades of research attest to the successful management and stabilization of lymphedema through nonsurgical means such as decongestive therapy, compression garments, manual lymphatic drainage, and rigorous skin care. Conversely, surgical treatment for lymphedema was historically quite limited and often reserved for the most severe and selected cases. The failure to develop novel surgical procedures seemed to result from a primitive understanding of lymphedema progression and only basic anatomical knowledge of the microcirculation.

Surgical management for lymphedema is still in its infancy and comprehensively relies on a coordinated interplay with conservative therapy.

Advances in real-time imaging of the lymphatic system and evolution of extremely fine surgical instruments has led to enhanced interest in surgical options for lymphedema. Surgical awareness has been reinforced through a greater exposure of lymphedema in the public eye and due to patient demand for a potential surgical choice. Despite this,

surgical management for lymphedema is still in its infancy and comprehensively relies on a coordinated interplay with conservative therapy.

A variety of surgical options have been proposed for lymphedema in the past. Some of these older techniques have limited application today but are still mentioned here for historical context. Surgical management for lymphedema can be classified into three categories based on mechanism of action. These include: 1) preventative methods; 2) excisional techniques, 3) physiological procedures, and 4) combined modalities. This article will briefly discuss each category and the various options within them.

Dr. James Kennedy MD, PhD, FRCSC, ABPS is a Plastic and Reconstructive surgeon and site chief at the South Health Campus hospital in Calgary, Alberta. He is a faculty member in the Cumming School of Medicine at the University of Calgary. His practice predominantly focuses on breast reconstruction, microsurgery, trauma, hand surgery, gender transformation, and lymphatic reconstruction.

1 Preventative methods

Preventative opportunities are often considered in secondary forms of lymphedema that may develop in an iatrogenic fashion after lymph node dissection or in response to another ancillary procedure. The various strategies either try to provide a guide towards a more detailed and refined dissection of lymphatic basins in cancer surgery, intraoperatively identify susceptible lymphatic channels and preserve them, and/or reconstruct damaged lymphatic channels at the time of potential injury. All are designed to prevent or limit the development of lymphedema at the time of or near the inciting event.

Sentinel Lymph Node Biopsy is a form of lymph node dissection in oncologic surgery that is based on removing or sampling lymph nodes that are the first order drainage of the affected region (e.g. breast) that may have cancer present. By “sampling” the first or second

Long-term

outcomes

for the latest techniques are lacking and direct comparisons are often difficult.

lymph node that may be draining the region of interest, the surgeon can determine if there has been spread to the lymph node basin before committing to a more extensive and definitive full lymph node dissection. Sentinel lymph node biopsy has been shown to reduce the incidence of lymphedema in breast cancer from 30% to 6%.1-3 Sentinel node biopsy has become and remains a major tool that is routinely applied in melanoma, breast and gynecological malignancies.

Reverse Lymph Node Mapping. Alternatively, in a region potentially affected by cancer, if lymph nodes that are draining the area could be differentiated from those draining a nearby extremity that is at risk of developing lymphedema, then it is possible to selectively sample only those from the region of interest. Reverse lymph node mapping entails using two different dyes that are injected at different regions in an attempt to separate the lymph node drainage patterns. This

TABLE 1

Surgical options for lymphedema

1 Preventative Methods

n Sentinel Lymph Node Biopsy

n Reverse Lymph Node Mapping

n LYMPHA

2 Excisional Techniques

n Charles Procedure

n Sistrunk Procedure

n Suction Assisted Lipectomy

3 Physiological Procedures

n Lymphatic-lymphatic Bypass

n Lymphatic-venous Anastomosis

n Vascularized Lymph Node Transfer

4 Combined Treatment

n Combination of above

allows identification of the lymph nodes that are draining the neighbouring limb while still allowing labelling of those nodes that are draining the affected body part (e.g. breast). The surgeon can then selectively leave those nodes that are draining the associated limb and sample only those that are from the affected body part. This has been shown to reduce the incidence of lymphedema to 4.1% in one meta-analysis.4 Despite being an attractive concept, reverse lymph node mapping has not been routinely utilized in clinical practice as often both dyes label the same lymph nodes and in that case, if those are left behind, then there is the chance of leaving occult metastases in the region.

Lymphedema Microsurgical Healing Approach (LYMPHA). Lymph nodes can be labelled and specific ones removed, as previously mentioned, but lymphatic channels are still likely violated to some degree. Instead of leaving the damaged lymphatic channels, LYMPHA entails reconstructing them by rerouting the damaged channels into nearby larger veins at the time of the initial surgery.5 Despite being an appealing concept, its practicality is questionable since not every patient will develop lymphedema from surgical lymph node dissection. Therefore it has been hard to reason universally applying an additive and much longer procedure, with greater risk, to every patient. Furthermore, coordinating at least two surgeons to be available for this type of case may limit surgical care in an oncologic timely fashion.

2 Excisional techniques

Preventative strategies are unable to be applied to every patient and offer no benefit to those with established lymphedema. Many of the original surgical procedures for lymphedema tend to fall within the excisional category whereby surgeons concentrated on direct removal of lymphedematous tissue to reduce overall limb volume. The Charles and Sistrunk procedures are more of historical significance and only sporadically used today in the developed world.

Charles Procedure. This procedure is named after Major-General Sir Richard Henry Charles

who was a physician and surgeon to King Henry V. He originally described surgical management of elephantiasis of the scrotum yet never actually performed the surgery on limbs.6 The Charles procedure involves a radical excision of skin, subcutaneous fat, and sometimes fascia from the affected extremity. Skin grafts are then placed onto remaining muscle to close the area of resection. It is simplistic and does remove significant bulk to the point that limbs that were previously not functional can be salvaged. However, it is rarely used today due to the extensive nature of the surgery, the potential for poor or delayed wound healing, poor cosmesis, and that it tends to make adjacent regions of lymphedema much worse. Moreover, lymphedema often returns in the operated extremity 5-10 years later and can be even more problematic.

Sistrunk Procedure.

In order to avert the poor cosmesis and extensive wounds that resulted from the Charles procedure, the Sistrunk modification was created to preserve skin and subcutaneous fat to avoid the need for a skin graft while still directly removing lymphedematous tissue. It tended to be divided into at least two stages whereby up to half of the excess volume of a limb was approached in each stage separated by a 3-6 month period. For instance, the first phase may involve making an incision and elevating skin and subcutaneous fat as a flap of tissue as far as possible both anteriorly and posteriorly. The underlying lymphedematous tissue is then excised down to fascia and removed, similar to the Charles procedure. The difference is that the flap of tissue that was elevated is laid back down to close the defect instead of using a skin graft from another region. The second phase entails making an incision directly opposite to the original incision and elevating flaps of tissue once again to allow removal of affected tissue that was not addressed in the first phase. Despite improving cosmesis and reducing the length of operative time, this technique never really gained much popularity as it had limited success.

Suction Assisted Lipectomy. Recent research has demonstrated that there is a unique interaction between lymphedema fluid and adipocytes that sparks excessive fat development. It has also been shown that overweight individuals are at risk for more severe presentations of lymphedema. It therefore makes sense to surgically address the fat compartment of lymphedematous limbs in some way. Physiological procedures (to be discussed in the next section) do not address the formed adipose tissue component.

Ablative surgical options thus far, have involved extensive incisions and long duration procedures to successfully remove large volumes of lymphedematous tissue. Suctionassisted lipectomy, or more commonly known as liposuction, on the other hand, is less invasive and since its development 40 years ago has been more routinely applied to lymphedema. Liposuction, following similar principles in cosmetic surgery, removes excess fat and some fibrous tissue utilizing a cannula (narrow surgical tube) connected

to a suction pump inserted through small incisions. Not only does it remove fat directly but the cannulas also create relative voids in the tissue that can allow greater compression postoperatively. The new volume is maintained through a smaller compression garment.

Liposuction equipment has evolved from standard suction assisted devices (that are still most commonly used), to power-assistance, ultrasonic, and laser that enhance tissue breakdown to increase efficiency. The utility of liposuction in lymphedema has shown very impressive results. Large volume reductions approaching 100% compared to the contralateral normal side have been reported.7 Brorson (2016)8 has also shown that volume reductions through liposuction can persist in long-term follow up studies with compression garment use. Furthermore, health-related quality of life indicators are improved and the incidence of cellulitis dramatically decreased with liposuction.9-10

3 Physiological procedures

Lymphedema develops due to an imbalance between lymph fluid production and the transport capacity of the lymphatic system. Attempts to address the transport capacity in the past were of limited success. More recent developments in reconstruction or augmentation of the transport mechanism, however, have created optimism and changed the landscape of lymphatic surgery.

Lymphaticlymphatic Bypass. Although not routinely applied and included more for historical interest, this procedure involves bypassing a lymphatic obstruction using other regional lymphatics from the same patient. For instance, in cases of leg lymphedema with an obstruction at the groin, lymphatic channels from the contralateral leg can be tunnelled over to the affected leg and anastomosed

A compliant patient, with worsening limb function, minimal improvement using nonsurgical means for at least 12 months, and realistic expectations are paramount.

to lymphatic channels so as to bypass the obstructed zone in the groin. Drainage then occurs from the affected leg into the contralateral unaffected side. Unfortunately this technique is fraught with risks such as the real potential of causing lymphedema in the normal leg and often involves very large scars, while the long-term patency of the lymphatics transferred is questionable.

Lymphatic-venous

Anastomosis (LVA). This technique was developed mainly in response to the issues with lymphatic-lymphatic bypass

and to address the superficial lymphatic system. Instead of using lymphatic channels from another area, intact lymphatic channels in the affected extremity are transferred under microscope guidance to nearby veins or venules. This requires having intact lymphatic vessels that have functioning smooth muscle cells that can transport lymphatic fluid into the nearby vein once transferred. The transfer serves as a shunt allowing flow of lymphatic fluid from an area of high pressure (lymphatic channel) to an area of low pressure (nearby vein). LVA has been shown to be effective in cases of mild-moderate lymphedema in reducing limb volume, improvement in overall symptoms, and decreasing the incidence of cellulitis.11-12 In one surgical session, that may last 5-6 hours,

small incisions are made to allow 3-5 of these transfers to take place. LVA can be repeated in the same extremity to allow additional transfers at a later point. The main drawback is that LVA requires a specially trained surgeon that is able to perform “supermicrosurgery” so that transfers and anastomoses of lymphatic vessels <1mm in size can be undertaken. It seems to be most effective in early secondary lymphatic disease with limited fibrosis.

Vascularized Lymph Node Transfer (VLNT).

TABLE 2

Potential risks and complications of the most common surgical treatment options for lymphedema

Procedure Potential Risks/Complications

All have general risks such as risk of anesthetic, bleeding, infection, and potential to make lymphedema worse.

Suction-assisted

•Contour irregularities to affected limb from over-resection lipectomy of certain areas compared to adjacent regions.

•Theoretically can damage intact lymphatic channels.

Not proven but can be reduced by suctioning longitudinally in limb.

•Minor wound healing problems

•Transient paresthesias (“tingling” to limb) that resolve with time.

Lymphatic-venous

•Longer operative time than liposuction anastomosis (LVA)

•Minor wound healing issues

•Potential for development of cellulitis

•Rare allergy to Indocyanine-green dye

Vascularized

•Potential to cause lymphedema at site of lymph node transfer lymph node harvest (VLNT)

•Potential major nerve or vessel injury to region of lymph flap harvest

•Larger scars and potential wound healing issues at both recipient and donor sites of lymph node flap

•Longer operative time risks

•Potential for flap loss and failure

One of the most progressive surgical options for lymphedema, VLNT encompasses transferring a soft tissue flap (skin, fat, and sometimes fascia), that also contains lymph nodes, from one part of the body to the affected extremity. It requires (under a microscope,) reconnecting arteries and veins that supply the flap of tissue with blood supply. Donor sites include areas such as groin, axilla, neck, and intra-abdominal omentum. The lymph node flap either acts as a “sump pump”, collecting lymph fluid and emptying into the connected vein, or may act as a mediator for new lymphatic channel growth.13-14 There is debate on the number of lymph nodes to transfer and where the lymph node flap should be placed in the affected limb. It is often a much lengthier surgery than any previously mentioned. The potential to cause lymphedema at the donor site is a real risk and the procedure can leave very noticeable scars to donor regions. However, vascularized lymph node transfer does seem to be effective in even severe cases and also with primary forms of lymphedema.15 The risk of causing lymphedema in the area of lymph node flap harvest can be reduced using a technique called reverse lymphatic mapping.16 Outcomes analysis has shown reductions in volume and circumference, improvements in quality of life domains, and decreased episodes of cellulitis.15,17-18

Autologous Free Tissue Transfer. There is some evidence that adding a flap of tissue (skin, fat, and muscle) with associated artery and vein, but without lymph nodes, can still

serve as a bridge for lymphatic outflow. This derives mainly from experimental animal models but also anecdotal evidence from using free abdominal tissue transfer for breast reconstruction in cases of breast cancer.19-20

4 Combined treatment

A better understanding of the goals of surgical management and the realities of individual procedures has led some lymphatic surgeons (me included) to adopt an integrated approach to lymphedema. Realizing that not all lymphedema patients are the same, the various techniques previously mentioned in this article can be applied in a way to maximize their individual benefits. For instance, in cases of severe lymphedema with a significant fibrous component, debulking the affected region using liposuction prior to attempting physiological lymphatic reconstruction only makes sense.

Conclusion

The surgical management of lymphedema remains an evolving process. Undoubtedly,

surgical options for lymphedema have advanced since the origin of the Charles procedure. Physiological procedures are being refined, as we have learned that LVA may be more effective in early stages of lymphedema while later stages may be more appropriate for VLNT. In more recent years, a combined approach incorporating a form of ablative procedure along with a physiological procedure(s) will ultimately provide the greatest benefit to patients. Still, long-term outcomes for the latest

techniques are lacking and direct comparisons are often difficult. As surgeons, we have to realize that not every lymphedema patient is the same and not every patient would benefit from surgical intervention. Defining appropriate patient selection remains challenging but should center around a few fundamental concepts. A compliant patient, with worsening limb function, minimal improvement using nonsurgical means for at least 12 months, and realistic expectations are paramount. The last aspect is often difficult to reconcile in the age of Internet medicine and exaggerated claims by a multitude of clinics and surgeons. It is worth reiterating that despite improvements in surgical options, it has not supplanted non-surgical therapy. Instead, surgery has more recently become an additional modality in an integrated treatment strategy for lymphedema patients that still requires lifelong self-care and management. LP

A full set of references can be found at www.lymphedemapathways.ca