Outcomes in Vascularized Lymph Node Transplantation in Rabbits: A Reliable Model for Improving the Surgical Approach to Lymphedema

Lymphatic Regeneration after Popliteal Lymph Node Excision and Implantation of Aligned Nanofibrillar Collagen Scaffolds: An Experimental Rabbit Model

Lymphedema presents significant challenges to patients' quality of life, prompting the exploration of innovative treatments, such as collagen scaffolds, aimed at treating and reducing the risk of lymphedema. We aimed to evaluate the preventive and therapeutic efficacy and the lymphangiogenic potential of implanted aligned nanofibrillar collagen scaffolds (BioBridgeTM) following the induction of secondary lymphedema in a rabbit model. Thirty rabbits were divided into treatment (G1), prevention (G2), and control (G3) groups. Secondary lymphedema was induced in all groups. BioBridgeTM implantation was performed in G2 and G1 on days 0 and 60, respectively. Follow-ups included hindlimb circumference measurements and indocyanine green lymphography at 0, 60, and 90 days. None of the study rabbits exhibited dermal backflow on day 0 before surgery. At 60 days, the incidence rates of dermal backflow in G1, G2, and G3 were 100%, 44.4%, and 90%, respectively. Furthermore, at 90 days, the incidence rates were 22.2%, 44.4%, and 90%, respectively. New linear lymphatic observation was seen in rabbits with resolved dermal backflow. The findings of this study demonstrated the capacity of BioBridgeTM scaffolds to induce new lymphatic vessel formation and reduce dermal backflow in secondary lymphedema in a rabbit model.

Editorial for the Special Issue "Vasorum Lymphaticorum: From the Discovery of the Lymphatic System to the New Perspectives in Microsurgical Reconstruction and Patient Rehabilitation"

Lymphedema is a complex clinical condition that appears as a result of the failure of the lymphatic system function, and it is characterized by edema, fibrosis, and adipose deposition [...].

Therapeutic Lymphangiogenesis Is a Promising Strategy for Secondary Lymphedema

Secondary lymphedema is caused by lymphatic insufficiency (lymphatic drainage failure) following lymph node dissection during the surgical treatment or radiation therapy of breast or pelvic cancer. The clinical problems associated with lymphedema are reduced quality of life in terms of appearance and function, as well as the development of skin ulcers, recurrent pain, and infection. Currently, countermeasures against lymphedema are mainly physical therapy such as lymphatic massage, elastic stockings, and skin care, and there is no effective and fundamental treatment with a highly recommended grade. Therefore, there is a need for the development of a fundamental novel treatment for intractable lymphedema. Therapeutic lymphangiogenesis, which has been attracting attention in recent years, is a treatment concept that reconstructs the fragmented lymphatic network to recover lymphatic vessel function and is revolutionary to be a fundamental cure. This review focuses on the translational research of therapeutic lymphangiogenesis for lymphedema and outlines the current status and prospects in the development of therapeutic applications.

Current Advancements in Animal Models of Postsurgical Lymphedema: A Systematic Review

Significance: Secondary lymphedema is a debilitating disease caused by lymphatic dysfunction characterized by chronic swelling, dysregulated inflammation, disfigurement, and compromised wound healing. Since there is no effective cure, animal model systems that support basic science research into the mechanisms of secondary lymphedema are critical to advancing the field. Recent Advances: Over the last decade, lymphatic research has led to the improvement of existing animal lymphedema models and the establishment of new models. Although an ideal model does not exist, it is important to consider the strengths and limitations of currently available options. In a systematic review adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we present recent developments in the field of animal lymphedema models and provide a concise comparison of ease, cost, reliability, and clinical translatability. Critical Issues: The incidence of secondary lymphedema is increasing, and there is no gold standard of treatment or cure for secondary lymphedema. Future Directions: As we iterate and create animal models that more closely characterize human lymphedema, we can achieve a deeper understanding of the pathophysiology and potentially develop effective therapeutics for patients.

Animal Models Used in the Research of Vascularized Lymph Node Transfer: A Systematic Review

BACKGROUND

Lymphedema is a common adverse consequence of breast cancer therapy, while still relatively little is known about its pathophysiology. Several treatment options emerged over the past decades, and among them, vascularized lymph node transfer (VLNT) seems to be particularly promising. Animal models are indispensable to improve our understanding of the underlying processes surrounding the transplantation of a vascularized lymph node. This review aimed to systematically evaluate animal models of VLNT and compare their advantages and disadvantages.

MATERIALS AND METHODS

A systematic review of literature in the Scopus, Web of Science, and Ovid MEDLINE databases was conducted according to the PRISMA guidelines to identify all studies on animal models used for the research of VLNT. The algorithm used in search of articles was "Vascularized Lymph Node Transfer" AND "Model". Articles were manually verified for relevance to the topic. The resulting models were assessed for their suitability for VLNT research.

RESULTS

The literature search yielded a total of 233 studies after duplicates removal. Of those, 217 were excluded based on title and abstract review. Another study was excluded after reviewing the full-text article leaving 15 eligible studies to be included in this review article.

CONCLUSIONS

Rats were found to be the most dominantly used animal model in the VLNT research, although other models had their benefits. The main areas of study were the functionality of VLNT within or without a preinduced lymphedema, its response to ischemia, and clarification of lymphatic pathways reestablishment following VLNT.

A prospective study on combined lymphedema surgery: Gastroepiploic vascularized lymph nodes transfer and lymphaticovenous anastomosis followed by suction lipectomy

BACKGROUND

There is no consensus on the appropriate treatment of lymphedema. Proposed techniques include lymphaticovenous anastomosis (LVA), vascularized lymph nodes transfer (VLNT), and suction lipectomy (SL). The benefit of combined procedures has also been postulated. In this prospective study, a combined protocol is proposed as an alternative to single-procedure strategies.

METHODS

Between January 2016 and October 2018, we enrolled patients with secondary lymphedema of lower limbs, stage II-III according to the International Society of Lymphology, progressive swelling and skin tonicity >60. Thirty-seven consecutive patients were dichotomized into group I, undergoing VLNT, and group II undergoing VLNT and LVA. Gastroepiploic lymphnode flap was harvested through laparoscopy, and in the same operation, LVAs were performed in group II on the basis of indocyanine green lymphography and patent blue findings. Two weeks later, SL was performed in all the patients. Patients were prospectively evaluated through clinical examination, circumference measurement, and skin tonicity.

RESULTS

The average follow-up was 2 ± 0.8 years. The first consecutive 21 patients were treated with VLNT followed by SL. The next 16 patients underwent combined VLNT and LVA, followed by SL. A mean of 2.4 LVAs were performed. A significant difference in the postoperative circumference measurements was found overall (p < .05): 52.6 ± 18.9 above the knee, 42.9 ± 25 below the knee, 36.2 ± 37 at foot. The postoperative tonicity dropped by 12.7 ± 6.3% (p < .05). The episodes of cellulitis significantly decreased to 0.1 ± 0.3 (p < .05).

CONCLUSIONS

LVA, VLNT, and SL can be integrated together in a combined approach, in synergy to enhance the outcomes.