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LYMPH NODE TRANSFER IN COMBINATION WITH A DIEAP-FLAP BREAST RECONSTRUCTION BY BREAST CANCER RELATED LYMPHEDEMA: PROMISING OR WRONG APPROACH?
SEIDENSTUECKER K., ZELTZER A., HAMDI M.
Dpt of Plastic Surgery, University Hospital Brussels, Belgium
Introduction: Recent articles report that surgery can effectively treat secondary lymphedema. The mechanisms of lymph node transfer have been discordant between different publications but this procedure showed promising results. Intrinsic lymphovenous connections have been previously shown to exist in the transferred flap. But if you transfer the nodes together with the abdominal wall in case of DIEAP + VLNT – don’t you transfer nodes with the belonging draining region? Why should the nodes start changing the draining direction and should drain the arm after being transferred to the axillary region?
Material and Methods: Since 2007 the senior author performs vascularized lymph node transfer (VLNT) in combination with autologous breast reconstruction with DIEAP (Deep inferior epigastric artery perforator) flap. In the long time follow up we regarded in some cases that the thoracic wall including the breast region had less swelling and the patient improve regarding the mobility of the arm. But the circumferences of the arm remained nearly the same. We are now going to reevaluate our DIEAP + VLNT group by performing lymphodynamic evaluation using ICG indocyanine green to study the migration direction of the transferred nodes.
Results: On spec that the transferred nodes didn´t drain the affected limb we change our operative approach and separate the two in one procedure. Also in need of an autologous breast reconstruction we perform two operations: the breast reconstruction with the DIEAP flap and the node transfer as a vascularized groin flap, harvest most common on the superficial circumflex iliac artery perforator (SCIAP) flap.
Conclusions: The vascularized lymph node transfer is a value option for the operative treatment of lymphedema. By breast cancer related lymphedema the combination of a node transfer and an autologous breast reconstruction with a DIEAP flaps appeared to be an elegant solution but our clinical follow up let us review our approach and modified it into a two stage separate operation.
HEADING TOWARDS AN ARTIFICIAL LYMPHATIC VESSEL TO TREAT LYMPHEDEMA
M. PISANO 1*, V. TRIACCA 1*, L. MAZZOLAI 3, M.A. SWARTZ 1,4
1 Institute of Bioengineering, EPFL, Lausanne, Switzerland
2 Radio-oncology Service, CHUV, Lausanne, Switzerland
3 Angiology Service, CHUV, Lausanne, Switzerland
4 Institute for Molecular Engineering, University of Chicago, IL, USA. * Authors contributed equally to this work
Introduction: Despite recent advances in pharmacological research and microsurgery, lymphedema remains an incurable disease that deeply affects patient’s quality of life. There is an urgent need for innovative approaches to restore continuous lymph flow drainage in affected tissues, as lymphatic vessels do in healthy people. To this end, we are using engineering tools to develop an implantable device draining interstitial fluid from the subcutis and continuously transporting it to the venous circulation. This would re-establish a homeostatic fluid equilibrium in affected limb, thus functioning as an artificial lymphatic vessel. Here we compare the biocompatibility of various materials, and present a new design for a micropump-based prototype to be evaluated in acute and chronic edema models.
Materials and Methods: For biocompatibility studies, medical grade silicone tubes (Novimed AG, Dietikon, CH) were implanted subcutaneously in the back of Wistar rats for 1 month. Tubes were either uncoated or coated with 2-methacryloyloxyethyl phosphorylcholine (MPC) or with C-Parylene (Specialty Coating Systems, Indiana, USA). The acute edema model was obtained by subcutaneously injecting a solution of 1.5% glycine in saline in the back of Wistar rats. A catheter connected either to an external pump or to an implantable one, was subcutaneously inserted and amount of fluid retrieved by the pump was measured. The chronic lymphedema model was obtained following the protocol by Yang et al. (PRSGO, 2014), based on the removal of inguinal and popliteal lymph nodes, cauterization of collecting vessels and irradiation in the inguinal area.
Results: As a proof-of-concept, we verified that it is possible to drain fluids from the subcutaneous space using porous silicone tubings, and an external pump applying negative pressure in an acute edema model. Foreign body reaction to the coated silicon tubing is being currently evaluated in rats. Our prototype design for a permanent draining implant consists in a system of micropumps and catheters implanted in the subcutis. The catheters, having multiple access pores on their lateral surfaces, are inserted at the level of the edematous area in the affected limb, and are integrated with a set of micropumps connected in series, which will drain the edematous fluid to a vein through a final impermeable output catheter.
Conclusions: Here we propose a new approach to treat lymphedema, applying engineering principles to restore lymph drainage from the edema to the venous circulation, thus opening the way to the development of an artificial lymphatic vessel.
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THE EUROPEAN JOURNAL OF LYMPHOLOGY - Vol. XXVI - Nr. 72 - 2015