Surgical research, staging-guided technical procedures and long-term clinical outcomes for the treatment of peripheral lymphedema: the Genoa Protocol

Citation: Campisi CC, Molinari L, Campisi CS, Villa G, Fulcheri E, and Campisi C (2020) Surgical research, staging-guided technical procedures and long-term clinical outcomes for the treatment of peripheral lymphedema: the Genoa Protocol. J Surg Surgical Res 6(1): 041-050. DOI: https://dx.doi.org/10.17352/2455-2968.000096 https://dx.doi.org/10.17352/jssr DOI: 2455-2968 ISSN: C L IN IC A L G R O U P


Introduction
Peripheral lymphedema remains an often poorly recognized disease that causes signifi cant morbidity in advanced cases, in terms of physical limitations, infection risk, and seriously compromised lifethreatening condition [1,2].
Conservative treatments are time consuming and expensive, and can be ineffective in halting the progression of the disease [2,7].
The development, in the past 50 years, of surgical techniques to restore lymphatic fl ow offers a treatment that targets not only more than symptomatic relief, but also a functional repair of the underlying problem of lymph stasis.
Initial procedures involved lymph nodal-venous shunts, but these were associated with a high failure rate due to the thrombogenic effect of the lymph node pulp entering the venous system and re-endothelization of the lymph node surface [8][9][10].
Anastomoses are performed at a single site using larger superfi cial and deep lymphatic vessels, attached to collateral branches of the main veins close to vein valves, to avoid backfl ow of blood and the closure of the anastomoses.
Microsurgical approach is planned on the guide of preoperative superfi cial and deep lymphoscintigraphy, combined with calculation of Transport Index [16][17][18].
Blue Patent Violet (BPV) Lymphochromic Test and Indocyanine Green Microlymphography (ICG Test) are intraoperatively properly combined to select both superfi cial and deep lymph collectors.
A single-site approach minimizes the number of incisions and thereby potential entry sites for infections.
The retrospective evaluation of this considerable surgical experience is described with reference to the treatment of both primary and secondary peripheral lymphedemas.

Materials and methods
• Clinical registry, demographic characteristics, and description of surgical techniques.
Between 1973 and 2020, 5.046 cases have been treated by microsurgery for peripheral lymphedema in Genoa, Italy ( Figure 1): both upper and lower limb lymphedema, with primary and secondary etiology, at early and late stages.
The two microsurgical techniques utilized in these procedures were derivative MLVA or reconstructive MLVLA (Figures 2,3).

Abstract
The Author 's vast surgical experience in the treatment of primary and secondary peripheral lymphedema is reported. The objective is to describe the techniques and the long-lasting clinical outcomes based on more than 45 years research and clinical applications, with particular reference to staging-guided derivative and reconstructive lymphatic microsurgery at a single site, and to complementary, sequential, minimally invasive procedures of selective liposuction. 5.046 cases of patients (demographic characteristics are at length described) affected by upper and/or lower limb lymphedema, between 1973 and 2020, underwent lymphatic microsurgery and, between 2012 and 2020, Fibro-Lipo-Lymph-Aspiration according to Lymph Vessel Sparing Procedure (FLLA-LVSP), for latest stages of Lymphedema previously treated by Lymphatic Microsurgery with partial improvement of the disease. Derivative Multiple Lymphatic-Venous Anastomoses (MLVA) or, in selected cases of Phlebolymphedema absolutely contraindicating derivative procedures, lymphatic pathway reconstruction, using interpositioned vein grafted shunts (Multiple-Lymphatic-Venous-Lymphatic-Anastomose /MLVLA), above all at lower limbs, were performed at a single site, either the brachial-axillary or inguinal-crural region.
Adopted surgical techniques are described in detail. As far as exposition of results is concerned, patients were followed up for a minimum of 5 years to over 20 years. Clinical outcomes included excess limb volume (ELV), frequency of dermatolymphangioadenitis (DLA) attacks, lymphoscintigraphy, and use of conservative therapies.
Compared with preoperative conditions, patients obtained signifi cant reduction in ELV of over 90%, with an average follow-up of 10 years or more. Over 96% of patients with earlier stages of disease (stage IB or IIA) progressively stopped using conservative therapies and over 80% of patients with later stages (stages IIB and III) signifi cantly decreased the frequency of physical therapies and discontinued compressive garments or stockings. DLA attacks considerably reduced by over 95%.
MLVA or MLVLA techniques when performed at a single site produce excellent outcomes in the treatment of both primary and secondary lymphedemas, giving the possibility of a complete restoration of lymphatic fl ow in early stages of disease, when tissue changes are minimal. For late stages of lymphedema only partially responding to MLVA or MLVLA, FLLA-LVSP sequential procedures can signifi cantly improve the long-term clinical outcomes.
Staging-guided treatment of peripheral lymphedema, according to Authors' Genoa Protocol, carries out contextual target of primary, secondary and tertiary prevention in the potential worsening of the disease.

• Description of surgical techniques
In general, the MLVA technique was adopted.
Several healthy-appearing lymphatics located at the single operative site were directly introduced into the selected vein by a U-shaped stitch (using 8/0 to 10/0 prolene sutures, depending on the caliber of the vessels), and then adhered to the vein cut-end by means of additional stitches between the vein border and peri-lymphatic tissue. Finally, the U-shaped stitch was removed to avoid occluding the lymphatic collectors.
Blue Patent Violet dye (BPV, a sodium or calcium salt of diethylammonium hydroxide) stained the well-functioning lymphatics blue, allowing visualization under the operating microscope of the passage of the lymph into the vein, at the completion of the anastomoses, to ensure the patency of these joins ( Figure 2).

Blue Patent Violet Lymphochromic Test and Indocyanine
Green Microlymphography (ICG Test) can be properly combined in this procedure, to select both superfi cial and deep lymph collectors, allowing to identify 3 anatomic levels of the limb lymphatic network: level 1, superfi cial-subdermic; level 2, superfi cial-epifascial; level 3, subfascial or deep ( Figure 4).     Primary lymphedemas were usually associated with lymph nodal dysplasias (LAD II, according to Papendieck's defi nition) ( Table 1) [19], with hyperplastic lymph nodes, sinus histiocytosis, and a thick and fi brous capsule with microlymphangioadenomiomatosis. In these cases, lymphatic obstruction was evident due to alterations of the lymphatic vessels that appeared dilated with thickened walls and where the smooth muscle cells were reduced in number and fragmented with fi brotic elements [8].
A score of less than 10 signifi es a normal TI, and a score ≥ 10 signifi es a pathological TI [18].
Duplex scan was performed in all patients to identify any venous disorder that might be contributing to the edema. In most patients, it was possible to correct this venous dysfunction at the same time as the microsurgery such as performing valvular plasty for venous insuffi ciency with 6/0 nylon sutures. In the minority of cases non-surgically correctable venous pathology was a contraindication for undertaking MLVA. In these cases, it was possible to perform MLVLA to reconstruct a new lymphatic pathway.
The most commonly used technique was the Author's (CC) interposition of an autologous vein graft between the lymphatics above and below the site of obstruction in the lymphatic fl ow [22][23][24] (Figure 3). The venous segment can be harvested from the same operative site or from the forearm (typically the cephalic vein).
The length of the graft varied from 7 to 15 cm. It is very important to collect several lymphatics at the distal cut-end of the vein segment to maintain the vein segment full of lymph and to avoid closure of the anastomotic sites, distal and proximal cut-ends, by thrombosis. The valves of the vein segment are useful to address the fl ow of lymph in the correct direction and to prevent lymph gravitational back fl ow. As with the MLVAs, the lymphatic collectors were directly introduced into the vein cut-ends by means of a U-shaped stitch, which was then stabilized with additional peripheral stitches and, fi nally, removed, leaving lymph collectors free into the vein.
In the last 8 years, an evaluation of the lymphatic pathways in the affected limbs, at the same time as the lymphatic surgery, based on ICG Test, has been usually combined with Blue Patent Violet (BPV) Lymphochromic Test, to properly select and to map both superfi cial and deep lymph collectors of the levels 1-2 and 3, thus planning the best surgical strategy by matching the operating results with pre-operative superfi cial and deep lymphoscintigraphic data and the related Transport Index. These data can be compared with other Authors' outcomes [29][30][31][32][33][34].

Results
Clinical outcomes improve the previous microsurgical  c. Earlier liver uptake of tracer, compared with preoperative parameters, taken as indirect evidence of the passage of lymph in the bloodstream.

Long-Term, Stable Results
In the long term, the ongoing reduction in ELV over time, together with follow-up lymphoscintigraphy, provided evidence of the patency of the anastomoses and absence of thrombosis.
No patient who was compliant with the CLyFT treatment protocol experienced a worsening of lymphedema. There was anecdotal evidence of signifi cant patient satisfaction with the clinical outcomes achieved and this was supported by the fact that vast majority of patients completed the minimum 5-years follow-up regimen.

Discussion
Lymphatic microsurgery represents an effective and, most importantly, a functional repair of the lymphatic system, that treats the underlying cause of the disease, the lymph stasis resulting from an obstruction in the fl ow of lymph.
The ideal indications for lymphatic microsurgery include the following:  Early stages of disease (IB, IIA, and early IIB).   MLVA and MLVLA are performed at a single tailored short incisional site [14,20,24,39].
Some plastic surgeons performing lymphatic microsurgery have adopted other techniques, making multiple scattered small incisions along the superfi cial-subdermic route of lymphatic pathways, distally down the lymphedematous limb, and performing a lymphatic-venular anastomosis at each incision [30][31][32][33][34]. However, such a so-called "supermicrosurgery" The rationale behind using a single-site technique is twofold: A proximal single-site surgery likely lowers the risk of infections, as there is less surface area for bacteria to breach the skin barrier. This is particularly relevant for advanced stages of disease with signifi cant lymph stasis and impaired loco-regional immune function [35][36][37][38]. Incisions made in the distal area of a lymphedematous limb may increase the risk of postoperative infections.
The caliber of the lymphatic vessels increases proximally.
Not only these vessels are easier to use for creating microanastomoses, but they also allow a greater amount of lymph to fl ow through each anastomosis, thus realizing a longlasting positive lymphatic-venous one-way pressure gradient.
This is very important when trying to redress the balance of fl uid in and out of the limb [14].
Super-microsurgery using small caliber vessels, while technically very impressive and exciting, may not be suffi cient to restore lymphatic fl ow in a limb, especially in late stage lymphedema.
There is an argument against the use of larger caliber lymph vessels and veins, however, it means that the pressure difference between the venous and lymphatic systems is too great for preventing thrombosis of the anastomoses when using these larger vessels. As matter of fact, Genoa MLVA technique takes measures to overcome this pressure difference by creating the anastomoses in close proximity to a valve in the vein. In this way, the valvular pumping creates a suction that pulls the lymph immediately through the anastomosis preventing thrombosis ("fl utter valve mechanism", with subsequent "valve draining micro-pump" physiological phenomenon).
The end-to-end approach realized in lymphatic-venular anastomoses, in contrast, allows the close contact of lymph and blood without this additional suction phenomenon and may, therefore, lead to thrombosis of the anastomoses.
The MLVA, using lymphatic vessels with the perilymphatic tissue, entirely ensure that these vessels are over time well functioning and this also helps to prevent thrombosis.
In addition, the administration of antithrombotic medications (low molecular weight heparin-LMWH, immediately postoperatively followed by low doses of aspirin Lymphatic Microsurgery is able to offer excellent outcomes when applied early in the disease process, where a complete resumption of lymphatic fl ow in the long term is achievable.
For advanced cases of peripheral lymphedema, only partially responding to lymphatic microsurgery, FLLA-LVSP sequential, loco-regional and additional minimally invasive option can determine highly signifi cant progress in the longterm control of the disease.
Preferably, microsurgery would be adopted as a preventive measure for all patients identifi ed as "at risk for lymphedema" when undergoing surgery that may disrupt lymph fl ow in the axillary or inguinal-crural regions.
Genoa protocol is able to realize, by staging-guided lymphedema surgical treatment, the consequent Primary, Secondary and Tertiary Prevention in the potential progressive worsening of lymphostatic disease.