Peripheral T cell profiling reveals downregulated exhaustion marker and increased diversity in lymphedema post-lymphatic venous anastomosis

Surgical treatments of lymphedema-a literature review on robot-assisted lymphovenous anastomosis (LVA)

Background and Objective

Lymphedema is a common issue after surgery and oncologic treatment, affecting millions of people worldwide. A better understanding of the condition has provided an increasing possibility of a tailormade treatment plan, and with improvement in surgical technique, we now have several surgical treatments to offer, including the lymphovenous anastomosis (LVA). Considering the size of lymph vessels used for LVA, sometimes as small as 0.3 mm, there is a need for improvement of the technical aspects of the procedures. This paper explores the potential of robotic assistance in LVA surgery as an innovative approach to overcome the limitations of human dexterity.

Methods

A literature review was performed on 2023-12-22 using PubMed, Cochrane, and Embase databases to identify all previous publications on robotic LVA surgery, resulting in a total of 65 publications. Original publications in English were considered and after selection, a total of 5 publications were included in the review.

Key Content and Findings

Two surgical systems used in clinical practice were identified, the MUSA (Microsure) and the Symani Surgical System (Medical Microinstruments). Common topics for discussion include the increased precision the robot assistance provides, clinical outcomes, ergonomics, and the learning curve for aspiring robot surgeons. Anastomosis times were generally found to be longer initially, but several authors note that there is a steep learning curve with rapidly decreasing times with an increasing number of procedures. Overall clinical outcomes were comparable to those using manual anastomosis.

Conclusions

The use of robotics in LVA surgery, has shown promising results through clinical studies. Robotic assistance can help augment the technical capacity of a surgeon through motion scaling and tremor filtration, facilitating the most delicate steps of the LVA. The learning curve is steep, and the technique can hopefully make microsurgical reconstructions available to a broader number of patients. Further development can include haptic feedback, structured training programs, and cost optimization through dissemination of the technology.

The Role of Inflammation in Lymphedema: A Narrative Review of Pathogenesis and Opportunities for Therapeutic Intervention

Lymphedema is a chronic and progressive disease of the lymphatic system characterized by inflammation, increased adipose deposition, and tissue fibrosis. Despite early hypotheses identifying lymphedema as a disease of mechanical lymphatic disruption alone, the progressive inflammatory nature underlying this condition is now well-established. In this review, we provide an overview of the various inflammatory mechanisms that characterize lymphedema development and progression. These mechanisms contribute to the acute and chronic phases of lymphedema, which manifest clinically as inflammation, fibrosis, and adiposity. Furthermore, we highlight the interplay between current therapeutic modalities and the underlying inflammatory microenvironment, as well as opportunities for future therapeutic development.

Topical tissue nanotransfection of Prox1 is effective in the prophylactic management of lymphedema

Lymphedema is chronic limb swelling resulting from lymphatic dysfunction. There is no cure for the disease. Clinically, a preventive surgical approach called immediate lymphatic reconstruction (ILR) has gained traction. Experimental gene-based therapeutic approaches (e.g., using viral vectors) have had limited translational applicability. Tissue nanotransfection (TNT) technology uses a direct, transcutaneous nonviral vector, gene delivery using a chip with nanochannel poration in response to a rapid (<100 ms) focused electric field. The purpose of this study was to experimentally prevent lymphedema using focal delivery of a specific gene Prox1 (a master regulator of lymphangiogenesis). TNT was applied to the previously optimized lymphedematous mice tail (day 0) directly at the surgical site with genetic cargo loaded into the TNT reservoir: group I (sham) was given pCMV6 (expression vector backbone alone) and group II was treated with pCMV6-Prox1. Group II mice had decreased tail volume (47.8%) compared to sham and greater lymphatic clearance on lymphangiography. Immunohistochemistry showed greater lymphatic vessel density and RNA sequencing exhibited reduced inflammatory markers in group II compared to group I. Prox1 prophylactically delivered using TNT to the surgical site on the day of injury decreased the manifestations of lymphedema in the murine tail model compared to control.

Utilization of Noncontrast Magnetic Resonance Lymphangiography for Selection of Effective Surgical Method in Breast Cancer-Related Lymphedema

Background and Objectives: When considering surgery for patients with breast cancer-related lymphedema (BCRL), it is crucial to determine which surgery will be most effective for the patient and establish the indications for each surgery. Our study retrospectively compared the results of preoperative noncontrast MR lymphangiography (NMRL) performed on the lymphedematous limb of patients before surgery, with the aim of analyzing whether preoperative NMRL can be used as a criterion for determining the type of surgery. Materials and Methods: From January 2020 to June 2022, a total of 138 patients with lymphedema underwent surgery at Seoul National University Bundang Hospital. All patients underwent preoperative NMRL imaging and were classified into stages 1-3 based on the MRI severity index using the authors' previous reference. Three types of surgery, LVA, LVA + liposuction, and LVA + VLNT, were conducted on all patients. The effectiveness of the surgery was evaluated one year postoperatively using the interlimb volume difference before and after surgery, the fluid volume of the edematous limb measured by bioimpedance spectroscopy, and the subjective satisfaction of the patients through the Lymph Q questionnaire. Results: In this study, out of a total of 138 patients, 26 (19%) were MRI stage 1, 62 (45%) were stage 2, and 50 (36%) were stage 3. Of the 83 patients who underwent LVA surgery, the greatest decrease in interlimb volume difference was observed in stage 2 patients, and subjective satisfaction was also the most effective in stage 2. In the case of LVA + liposuction patients, a significant volume decrease and a high satisfaction were observed in stage 3 patients. In the case of LVA + VLNT patients, there was no difference in volume decrease according to the stage, but a greater decrease in body fluid volume was observed as the MRI severity index score increased through BIA. Conclusions: In conclusion, this study demonstrates that NMRL imaging is a useful modality for determining the most effective surgical method and predicting the surgical outcome in patients with lymphedema. This highlights the importance of using NMRL in the treatment planning of lymphedema patients.