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Lymphatic System Transfer (LYST)

LYST deliberately transfers vascularized lymph nodes together with mapped afferent lymphatic vessels, usually within a superficial circumflex iliac artery perforator (SCIP) flap. It is an evolving specialist option for selected patients with lymphedema. Published limb cohorts are small and uncontrolled; they do not establish faster recovery, superior drainage or freedom from compression compared with other operations.[1][2][3]

For treatment selection see Genital Lymphedema, Complex Decongestive Therapy, LVA and VLNT. Genital SCIP reconstruction is discussed separately in 3R / SCIP-LIFT, Abdelfattah's pedicled transfer and CHASCIP.

Distinguish the procedures​

ProcedureIntended lymphatic tissue
VLNTVascularized nodes and surrounding tissue; afferent vessels may be present without being deliberately mapped into a long unit
LYSTNodes plus deliberately mapped afferent collectors, maintained within vascularized tissue
LIFT / lymphatic vessel transferVascularized collector-bearing tissue without intentional node harvest
LVADirect microsurgical connection between suitable recipient lymphatics and veins

LYST aims to retain an organized drainage unit, but that unit still needs to integrate with the recipient lymphatic environment. Demonstrating dye passage within the harvested flap does not establish immediate drainage of the recipient limb. Proposed lymphangiogenic and immunologic mechanisms do not prove comparative clinical benefit.[1][4]

Names such as "lymphatic SCIP flap" are used for different designs. The author description of genital 3R / SCIP-LIFT preserves nodes around the vascular pedicle and transfers collector-bearing tissue; it should not be automatically relabeled as node-containing LYST.[5]

Selection and planning​

Consider reconstructive lymphatic surgery after evaluating the cause and distribution of edema, venous disease, fibrosis, recurrent infection, functional impairment and response to appropriate conservative care. Imaging and examination should identify usable lymphatic pathways and assess the donor region. No single ICG dermal-backflow pattern or ISL stage automatically selects LYST, VLNT or LVA; ISL's physical stages primarily describe extremities.[4][6]

Important planning questions are:

  • Can suitable lymphatics support LVA, or is tissue transfer being considered because of a more extensive defect or lack of usable channels?
  • Is there a safe, perfused donor unit with an appropriate vascular pedicle? Prior groin dissection, radiation or existing leg edema can change feasibility.
  • Does a pedicled flap reach without compression or twisting, or is free transfer required?
  • Is a separate excisional or skin-reconstruction procedure needed for irreversible genital disease?

High-frequency ultrasound can supplement ICG mapping by showing vessels and soft-tissue anatomy. Published ultrasound-planning experience supports feasibility, not a universal equipment requirement or guaranteed identification of every collector.[4][6]

Donor protection​

Do not define a node-harvest safe zone from surface landmarks alone. Lower-limb drainage can reach superficial inguinal nodes. Reverse lymphatic mapping identifies nodes and channels draining the donor leg so that they can be preserved; mapping of the proposed flap's afferent system serves a different purpose.[7][8]

The original free-LYST report used lower-limb technetium mapping and separate flank ICG injections. Tracer choice and injection sites must follow the specialist mapping protocol. In an 84-patient planning study, lower-limb drainage reached at least one superficial inguinal region in 38.1% of patients. No donor-leg lymphedema was observed after the 58 mapped flap harvests during the reported follow-up, but this does not establish zero lifetime risk.[1][8]

Donor counseling should include lymphedema, lymphatic leak or seroma, wound problems and the possibility that mapping will prevent use of the planned donor. Reverse mapping reduces avoidable injury; it cannot eliminate all risk.[1][6]

Operative principles​

The original report describes free SCIP-based LYST. These principles identify the intended operation; they are not a substitute for patient-specific flap and lymphatic mapping.[1][4]

  1. Map before harvest. Identify the afferent collector-bearing tissue, its nodal endpoint, arterial supply and venous outflow while preserving donor-leg drainage.
  2. Preserve the mapped unit. Raise vascularized tissue containing the selected collectors and nodes. Flap thickness follows their actual location; aggressive thinning can remove the target lymphatics or compromise perfusion.
  3. Prepare a suitable recipient bed. Release relevant scar when indicated and plan the flap orientation and vascular connections. Avoid a tight tunnel, pedicle torsion and pressure on the inset.
  4. Inset according to the mapped anatomy. In the initial series the node-containing end was placed proximally and free vascular anastomoses were performed. Recipient vessels and coverage were individualized.
  5. Monitor vascular and wound recovery. Plan compression and rehabilitation with the lymphatic team after protecting the healing flap and anastomoses.

A pedicled LYST flap retains its vascular connection and avoids a free-flap vascular anastomosis. It does not necessarily avoid microsurgery: five of the six patients in the 2026 pedicled limb report also underwent distal lymphovenous bypass. A benefit specifically from the pedicled flap, or from bypassing venous disease, cannot be isolated from that combined series.[3]

Clinical evidence​

ReportPopulation and findingsInterpretation
Original LYST, 2020Three women: two affected arms and one affected leg. All flaps survived; no donor complication was observed during mean 11-month follow-up. Compression resumed four weeks after surgery.Proof of concept. No control group; continued conservative treatment and short follow-up limit conclusions.[1]
Longer-term LYST, 2025Eight unilateral lower-limb patients; mean follow-up 39 months. The abstract reports improvement in excess-volume percentage and fewer cellulitis episodes.Small retrospective limb cohort. It does not establish genital efficacy or superiority over VLNT/LVA.[2]
Pedicled LYST, 2026Six patients with limb lymphedema and chronic venous disease; five also had distal bypass. Mean follow-up 31 weeks; mean LLIS and L-Dex decreases were 15 points and 30 units. No immediate complications were reported.Combined treatment, short follow-up and no comparator. "No immediate complications" is not zero complications over time.[3]

Genital series reporting excision plus lymphatic SCIP reconstruction use different flap designs and outcome measures. Their results cannot be pooled as LYST outcomes or compared with historical excision recurrence rates to prove a causal benefit of transferred nodes. The 26-patient Abdelfattah report is covered on its dedicated page.[5][9]

Similarly, a study of 31 women undergoing bilateral inguinofemoral dissection for vulvar cancer found less limb-volume increase on the side receiving a lymphatic SCIP reconstruction. The flap side was selected for reconstructive need, not randomized. This is not evidence for routine prophylactic LYST during prostate or bladder pelvic lymphadenectomy.[10]

Follow-up and counseling​

Document the treated limb or genital symptoms, episodes of cellulitis, objective measurements when appropriate, quality of life, compression use and both donor and recipient complications. Maintain skin care and reassess compression with the treating team; an improved score alone does not justify stopping it. Persistent or recurrent symptoms require evaluation of residual fibrosis, venous disease, lymphatic function and reconstructive complications.[1][6]

The available evidence supports feasibility in selected patients. It does not establish a universal recovery timeline, cure, guaranteed immune restoration or superiority of node-containing transfer over other lymphatic reconstruction.

References​

1. Yoshimatsu H, Visconti G, Karakawa R, Hayashi A. Lymphatic system transfer for lymphedema treatment: transferring the lymph nodes with their lymphatic vessels. Plast Reconstr Surg Glob Open. 2020;8:e2721. doi:10.1097/GOX.0000000000002721

2. Yoshimatsu H, Cho MJ, Karakawa R, et al. The role of lymphatic system transfer (LYST) for treatment of lymphedema: a long-term outcome study of SCIP flap incorporating the lymph nodes and the afferent lymphatic vessels. J Plast Reconstr Aesthet Surg. 2025;101:15–22. doi:10.1016/j.bjps.2024.11.052

3. Xu KY, Finkelstein ER, Wu S, Tadisina K, Mella-Catinchi J. Lymphatic system transfer (LYST) with pedicled SCIP for patients with lymphedema and concomitant chronic venous disease. Plast Reconstr Surg. 2026. doi:10.1097/PRS.0000000000012927

4. Visconti G, Bianchi A, Salgarello M, et al. Lymphatic tissue transfer: ultrasound-guided description and preoperative planning of vascularised lymph nodes, lymphatic units, and lymphatic vessels transfers. J Pers Med. 2022;12:1346. doi:10.3390/jpm12081346

5. Sun JM, Yamamoto T. Genital elephantiasis: Surgical treatment and reconstruction. J Chin Med Assoc. 2024;87:142–147. doi:10.1097/JCMA.0000000000001021

6. International Society of Lymphology. The diagnosis and treatment of peripheral lymphedema: 2023 consensus document of the International Society of Lymphology. Lymphology. 2023;56:133–151. Full consensus

7. Dayan JH, Dayan E, Smith ML. Reverse lymphatic mapping: a new technique for maximizing safety in vascularized lymph node transfer. Plast Reconstr Surg. 2015;135(1):277–285. doi:10.1097/PRS.0000000000000822

8. Broyles JM, Smith JM, Wong FC, et al. Single-photon emission computed tomographic reverse lymphatic mapping for groin vascularized lymph node transplant planning. Plast Reconstr Surg. 2022;150(4):869e–879e. doi:10.1097/PRS.0000000000009557

9. Abdelfattah U, Elbanoby T, Hamza F, et al. Treatment of advanced male genital lymphedema with a complete functional lymphatic system pedicled transfer. Urology. 2023;175:190–195. doi:10.1016/j.urology.2023.02.006

10. Caretto AA, Stefanizzi G, Fragomeni SM, et al. Lymphatic function of the lower limb after groin dissection for vulvar cancer and reconstruction with lymphatic SCIP flap. Cancers. 2022;14(4):1076. doi:10.3390/cancers14041076