Development of a rat model of lymphedema and the implantation of a collagen-based medical device for therapeutic intervention.

Secondary lymphedema is a common condition among cancer survivors, and treatment strategies to prevent or treat lymphedema are in high demand. The development of novel strategies to diagnose or treat lymphedema would benefit from a robust experimental animal model of secondary lymphedema. The purpose of this methods paper is to describe and summarize our experience in developing and characterizing a rat hindlimb model of lymphedema. Here we describe a protocol to induce secondary lymphedema that takes advantage of micro computed tomography imaging for limb volume measurements and visualization of lymph drainage with near infrared imaging. To demonstrate the utility of this preclinical model for studying the therapeutic benefit of novel devices, we apply this animal model to test the efficacy of a biomaterials-based implantable medical device.

Acupuncture Treatment for Breast Cancer-Related Lymphedema: A Randomized Pilot Study.

Background: Methods of conservative management for breast cancer-related lymphedema (BCRL) are burdensome in terms of time, cost, and convenience. In addition, many patients are not candidates for surgical treatment. Preliminary results have demonstrated possible beneficial effects of acupuncture for patients with BCRL. In this small pilot study, we examined the safety and feasibility of an acupuncture randomized control trial (RCT) in this patient cohort, utilizing a battery of standardized clinical and patient-centered outcome measures. Methods and Results: Patients with BCRL were randomized 2:1 to the acupuncture (n = 10) or the control (n = 4) group. Patients received acupuncture to the unaffected extremity biweekly for 6 weeks. Feasibility was defined as enrollment ≥80%, completion of ≥9 of 12 acupuncture sessions per person, and ≥75% completion of three of three measurement visits. To inform a future adequately powered RCT, we describe within-group changes in patient-centered outcomes, including circumferential measurements, bioimpedance spectroscopy, perometry, cytokine levels, and patient quality of life. Adverse events were systematically tracked. Fourteen patients completed the study. Of those who received acupuncture (n = 10), 8 completed all 12 acupuncture sessions, and 2 patients completed 11 sessions. Ninety-three percent of all participants completed all three measurement visits. There was no consistent improvement in arm volumes. Inflammatory marker levels had inconclusive fluctuations among both groups. All patients receiving acupuncture demonstrated an improvement in their functional quality-of-life score. No severe adverse events occurred. Conclusions: A randomized controlled study of acupuncture for BCRL is feasible. The acupuncture intervention is acceptable in this population, without safety concerns in a small sample and warrants further investigation.

The American Venous Forum, American Vein and Lymphatic Society and the Society for Vascular Medicine expert opinion consensus on lymphedema diagnosis and treatment.

BACKGROUND: Lymphedema imposes a significant economic and social burden in modern societies. Controversies about its risk factors, diagnosis, and treatment permeate the literature. The goal of this study was to assess experts' opinions on the available literature on lymphedema while following the Delphi methodology. METHODS: In December of 2019, the American Venous Forum created a working group tasked to develop a consensus statement regarding current practices for the diagnosis and treatment of lymphedema. A panel of experts was identified by the working group. The working group then compiled a list of clinical questions, risk factors, diagnosis and evaluation, and treatment of lymphedema. Fifteen questions that met the criteria for consensus were included in the list. Using a modified Delphi methodology, six questions that received between 60% and 80% of the votes were included in the list for the second round of analysis. Consensus was reached whenever >70% agreement was achieved. RESULTS: The panel of experts reached consensus that cancer, infection, chronic venous disease, and surgery are risk factors for secondary lymphedema. Consensus was also reached that clinical examination is adequate for diagnosing lymphedema and that all patients with chronic venous insufficiency (C3-C6) should be treated as lymphedema patients. No consensus was reached regarding routine clinical practice use of radionuclide lymphoscintigraphy as a mandatory diagnostic tool. However, the panel came to consensus regarding the importance of quantifying edema in all patients (93.6% in favor). In terms of treatment, consensus was reached favoring the regular use of compression garments to reduce lymphedema progression (89.4% in favor, 10.6% against; mean score of 79), but the use of Velcro devices as the first line of compression therapy did not reach consensus (59.6% in favor vs 40.4% against; total score of 15). There was agreement that sequential pneumatic compression should be considered as adjuvant therapy in the maintenance phase of treatment (91.5% in favor vs. 8.5% against; mean score of 85), but less so in its initial phases (61.7% in favor vs. 38.3% against; mean score of 27). Most of the panel agreed that manual lymphatic drainage should be a mandatory treatment modality (70.2% in favor), but the panel was split in half regarding the proposal that reductive surgery should be considered for patients with failed conservative treatment. CONCLUSION: This consensus process demonstrated that lymphedema experts agree on the majority of the statements related to risk factors for lymphedema, and the diagnostic workup for lymphedema patients. Less agreement was demonstrated on statements related to treatment of lymphedema. This consensus suggests that variability in lymphedema care is high even among the experts. Developers of future practice guidelines for lymphedema should consider this information, especially in cases of low-level evidence that supports practice patterns with which the majority of experts disagree.

Clinical Evaluation of a Novel Wearable Compression Technology in the Treatment of Lymphedema, an Open-Label Controlled Study.

A diagnosis of lymphedema comes with a lifetime requirement for careful self-care and treatment to control skin deterioration and the consequences of excessive fluid and protein buildup leading to abnormal limb volume and an increased risk of infection. The burden of care and psychosocial aspects of physical disfiguration and loss of function are associated with compromised quality of life (QoL). The current standard therapeutic intervention is complex decongestive therapy with manual lymph drainage and frequent wearing of compression garments. With insurance limitations on therapy visits and the time and travel required, additional home treatment options are needed. Pneumatic compression pumps that mimic the manual massage pressure and pattern are sometimes prescribed, but these are bulky, difficult to apply, and require immobility during treatment. An open-label pilot study in 40 subjects was performed to evaluate the QoL and limb volume maintenance efficacy of a novel wearable compression system (Dayspring™) that is low profile, easy to use, and allows for mobility during treatment. After 28 days of use, subjects had a statistically significant 18% (p < 0.001) improvement in overall QoL as measured by the Lymphedema Quality-of-Life Questionnaire compared with baseline. Individual QoL domains, and limb volume improved with therapy. Adherence was 98% over the course of the study. Results of the clinical evaluation suggest the Dayspring wearable compression device is safe and effective and improves QoL and limb volume. The novel, low-profile device is easy to use and allows for mobility during treatment, addressing a potential barrier to adherence with pneumatic compression devices.

Aligned nanofibrillar collagen scaffolds - Guiding lymphangiogenesis for treatment of acquired lymphedema.

Secondary lymphedema is a common disorder associated with acquired functional impairment of the lymphatic system. The goal of this study was to evaluate the therapeutic efficacy of aligned nanofibrillar collagen scaffolds (BioBridge) positioned across the area of lymphatic obstruction in guiding lymphatic regeneration. In a porcine model of acquired lymphedema, animals were treated with BioBridge scaffolds, alone or in conjunction with autologous lymph node transfer as a source of endogenous lymphatic growth factor. They were compared with a surgical control group and a second control group in which the implanted BioBridge was supplemented with exogenous vascular endothelial growth factor-C (VEGF-C). Three months after implantation, immunofluorescence staining of lymphatic vessels demonstrated a significant increase in lymphatic collectors within close proximity to the scaffolds. To quantify the functional impact of scaffold implantation, bioimpedance was used as an early indicator of extracellular fluid accumulation. In comparison to the levels prior to implantation, the bioimpedance ratio was significantly improved only in the experimental BioBridge recipients with or without lymph node transfer, suggesting restoration of functional lymphatic drainage. These results further correlated with quantifiable lymphatic collectors, as visualized by contrast-enhanced computed tomography. They demonstrate the therapeutic potential of BioBridge scaffolds in secondary lymphedema.

A pilot, prospective evaluation of a novel alternative for maintenance therapy of breast cancer-associated lymphedema [ISRCTN76522412].

BACKGROUND: Prospective investigations of complete decongestive lymphatic physiotherapy (CDPT), including manual lymphatic drainage (MLD), have validated the efficacy of these interventions for the initial reduction of edema and long-term maintenance of limb volume in lymphedema. However, CDPT demands substantial time and effort from patients to maintain these benefits; the treatments are not always well-accepted, and patients may suffer from a deterioration in quality-of-life or a time-dependent loss of initial treatment benefits. A new device designed for home use by the patient, the Flexitouch, has been developed to mechanically simulate MLD. We have undertaken a prospective, randomized, crossover study of the efficacy of the Flexitouch, when compared to massage, in the self-administered maintenance therapy of lymphedema. METHODS: A prospective, randomized, crossover study of maintenance therapy was performed in 10 patients with unilateral breast cancer-associated lymphedema of the arm. Each observation phase included self-administered treatment with the Flexitouch or massage, 1 hour daily for 14 days, respectively, followed by crossover to the alternate treatment phase. Each treatment phase was preceded by a 1 week treatment washout, with use of garment only. The sequence of treatment was randomly assigned. The potential impact of treatment modality on quality of life was assessed with serial administration of the SF-36. RESULTS: Statistical analysis disclosed that the order of treatment had no outcome influence, permitting 10 comparisons within each treatment group. Post-treatment arm volume reduced significantly after the Flexitouch, but not after self-administered massage. The patients' mean weight decreased significantly with Flexitouch use, but not with massage. The Flexitouch device was apparently well-tolerated and accepted by patients. Serial SF-36 administration showed no deterioration in physical or psychosocial scores compared to baseline measurements; there were no statistical differences in scores when the two treatment modalities were compared. CONCLUSION: This short-term prospective evaluation of the Flexitouch suggests that the device may provide better maintenance edema control than self-adiminstered massage in breast cancer-associated lymphedema. The apparent ease of use and reliability of response to the device suggest that further broad-scale testing is warranted.