Proposed pathway and mechanism of vascularized lymph node flaps

Lymphatic endothelial cell-targeting lipid nanoparticles delivering VEGFC mRNA improve lymphatic function after injury

Dysfunction of the lymphatic system following injury, disease, or cancer treatment can lead to lymphedema, a debilitating condition with no cure. Advances in targeted therapy have shown promise for treating diseases where conventional therapies have been ineffective and lymphatic vessels have recently emerged as a new therapeutic target. Lipid nanoparticles (LNPs) have emerged as a promising strategy for tissue specific delivery of nucleic acids. Currently, there are no approaches to target LNPs to lymphatic endothelial cells, although it is well established that intradermal (ID) injection of nanoparticles will drain to lymphatics with remarkable efficiency. To design an LNP that would effectively deliver mRNA to LEC after ID delivery, we screened a library of 150 LNPs loaded with a reporter mRNA, for both self-assembly and delivery in vivo to lymphatic endothelial cells (LECs). We identified and validated several LNP formulations optimized for high LEC uptake when administered ID and compared their efficacy for delivery of functional mRNA with that of free mRNA and mRNA delivered with a commercially available MC3-based LNP (Onpattro™). The lead LEC-specific LNP was then loaded with VEGFC mRNA to test the therapeutic advantage of the LEC-specific LNP (namely, LNP7) for treating a mouse tail lymphatic injury model. A single dose of VEGFC mRNA delivered via LNP7 resulted in enhanced LEC proliferation at the site of injury, and an increase in lymphatic function up to 14-days post-surgery. Our results suggest a therapeutic potential of VEGFC mRNA lymphatic-specific targeted delivery in alleviating lymphatic dysfunction observed during lymphatic injury and could provide a promising approach for targeted, transient lymphangiogenic therapy.

Personalizing Locoregional Therapy in Patients With Breast Cancer in 2024: Tailoring Axillary Surgery, Escalating Lymphatic Surgery, and Implementing Evidence-Based Hypofractionated Radiotherapy

The management of axillary lymph nodes in breast cancer is continually evolving. Recent data now support omitting axillary lymph node dissection (ALND) in most patients with metastases in up to two sentinel lymph nodes (SLNs) during upfront surgery and those with residual isolated tumor cells after neoadjuvant chemotherapy (NACT). In the upfront surgery setting, ALND is still indicated, however, in patients with clinically node-positive breast cancer or more than two positive SLNs and, after NACT, in case of residual micrometastases and macrometastases. Omission of the sentinel lymph node biopsy (SLNB) can be considered in many postmenopausal patients with small luminal breast cancer, particularly when axillary ultrasound is negative. Several randomized controlled trials (RCTs) are currently aiming at eliminating the remaining indications for ALND and also establishing omission of SLNB in a broader patient population. The movement to deescalate axillary staging is in part because of the association between ALND and lymphedema, which is swelling of an extremity because of lymphatic damage and obstructed lymphatic drainage. To reduce the risk of developing this condition, patients undergoing ALND can undergo reverse mapping of the axilla and immediate reconstruction or bypass of the lymphatics from the involved extremity. Decongestion and compression are the foundation of conservative treatment for established lymphedema, while lymphovenous bypass and lymph node transfer are surgical procedures to address the physiologic dysfunction. Radiotherapy is an essential component of breast locoregional therapy: more than three decades of radiation research has optimized treatment according to patient's risk of local recurrence while substantially reducing the number of treatment visits. High-quality RCTs have shown the efficacy and safety of hypofractionation-more than 2Gy radiation dose per treatment (fraction)-significantly reducing the burden of radiotherapy treatment for many patients with breast cancer. In 2024, guidelines recommend no more than 15-16 fractions for whole-breast and nodal radiotherapy, with some recommending five fractions for whole-breast radiotherapy. In addition, simultaneous integrated boost (SIB) has been shown to be noninferior to sequential boost with regards to ipsilateral breast tumor recurrence with similar or reduced long-term side effects, also reducing overall treatment length. Further RCTs are underway investigating other indications for five fractions, including SIB and regional node irradiation, such that, in future, it may be possible for the majority of breast radiotherapy patients to be treated with a 1-week course. This manuscript serves to outline the latest updates on axillary surgical staging, lymphatic surgery, and evidence-based radiotherapy in the treatment of breast cancer.

Safety and efficacy of intracranial vascularized submental lymph node transfer for treating hydrocephalus

Hydrocephalus is routinely treated with ventriculoperitoneal shunt drainage of cerebrospinal fluid (CSF), a procedure plagued by high morbidity and frequent revisions. Vascularized submental lymph node (VSLN) transplants act as lymphatic pumps to drain interstitial fluid (ISF) from lymphedematous extremities. As the field of neuro-lymphatics comes to fruition, we hypothesize the efficacy of VSLN in the drainage of intracranial CSF-ISF. We report novel placement of VSLN in the temporal subdural space in two patients diagnosed with symptomatic communicating hydrocephalus. At a minimum follow-up of 1 month postoperatively, both experienced radiological and clinical improvements.

Lymphangiogenesis after nonvascularized lymph node transplantation: Lymphangiographic findings in mice and minipigs

The establishment of new connections after NVLNT (non-vascularized lymph node transplantation) is still poorly understood. The purpose of this study was to investigate lymphatic connections after NVLNT using lymphangiography. In a mice model, 40 mice were allocated to undergo NVLNT or sham surgery. On day 21 after NVLNT, the lymphatic vessels were observed on near-infrared fluorescence imaging with indocyanine green. In a minipig model, 12 minipigs underwent NVLNT. On day 14 after NVLNT, the transplanted lymph node and donor site were checked by ultrasound, and minipigs with viable transplanted LNs were allocated to lipiodol lymphangiography or MR lymphangiography groups. Transplanted LN engraftment was examined with immunohistochemical staining. After NVLNT in mice, the signal intensities in the popliteal region at 3 minutes and 5 minutes were higher in the transplanted side than the control side (21.3 ± 8.1 vs. 11.0 ± 4.6 at 3 minutes, 26.7 ± 6.8 vs. 19.7 ± 5.9 at 5 minutes), while in the sham group, there were no significant differences between sides. In minipigs, lipiodol lymphangiography (n = 5) showed Lipiodol accumulation in transplanted LNs with innumerable newly formed lymphatic vessels and lymphovenous shunts. MR lymphangiography (n = 5) showed higher enhancement on the transplanted side compared to the control side. Histology showed successful engraftment of transplanted LNs in 16 out of 20 (80%) mice and 9 out of 12 (75%) minipigs. Omnidirectional lymphangiogenesis forming a dense lymphatic network and spontaneous formation of lymphovenous shunts were shown after NVLNT.

Lentiviral overexpression of VEGFC in transplanted MSCs leads to resolution of swelling in a mouse tail lymphedema model

BACKGROUND

Dysfunction of the lymphatic system following injury, disease, or cancer treatment can lead to lymphedema, a debilitating condition with no cure. Despite the various physical therapy and surgical options available, most treatments are palliative and fail to address the underlying lymphatic vascular insufficiency driving lymphedema progression. Stem cell therapy provides a promising alternative in the treatment of various chronic diseases with a wide range of therapeutic effects that reduce inflammation, fibrosis, and oxidative stress, while promoting lymphatic vessel (LV) regeneration. Specifically, stem cell transplantation is suggested to promote LV restoration, rebuild lymphatic circulation, and thus potentially be utilized towards an effective lymphedema treatment. In addition to stem cells, studies have proposed the administration of vascular endothelial growth factor C (VEGFC) to promote lymphangiogenesis and decrease swelling in lymphedema.

AIMS

Here, we seek to combine the benefits of stem cell therapy, which provides a cellular therapeutic approach that can respond to the tissue environment, and VEGFC administration to restore lymphatic drainage.

MATERIALS & METHODS

Specifically, we engineered mesenchymal stem cells (MSCs) to overexpress VEGFC using a lentiviral vector (hVEGFC MSC) and investigated their therapeutic efficacy in improving LV function and tissue swelling using near infrared (NIR) imaging, and lymphatic regeneration in a single LV ligation mouse tail lymphedema model.

RESULTS

First, we showed that overexpression of VEGFC using lentiviral transduction led to an increase in VEGFC protein synthesis in vitro. Then, we demonstrated hVEGFC MSC administration post-injury significantly increased the lymphatic contraction frequency 14-, 21-, and 28-days post-surgery compared to the control animals (MSC administration) in vivo, while also reducing tail swelling 28-days post-surgery compared to controls.

CONCLUSION

Our results suggest a therapeutic potential of hVEGFC MSC in alleviating the lymphatic dysfunction observed during lymphedema progression after secondary injury and could provide a promising approach to enhancing autologous cell therapy for treating lymphedema.

Current trends in postmastectomy breast reconstruction

PURPOSE OF REVIEW

Breast reconstruction is established as integral part of the treatment. New materials, indications and surgical techniques are subject to rapid modification to further improve safety, quality and longevity.

RECENT FINDINGS

Skin-sparing-mastectomy is accepted as an appropriate alternative in risk-reducing and many breast cancer patients, further reducing conventional mastectomy patterns.Radiation in combination with reconstruction is still challenging with no clear advances reducing skin-toxicity.Autologous reconstructions, not only in radiation settings, are turning to a first line approach. A trend driven by improved techniques to minimize morbidity and flap-variations.Breast implant surfaces associated with a high risk of Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) are now withdrawn. The residual risk for the remaining implant styles is not known, but can be expected considerably lower than estimations published presently.In order to reduce local complications, supplemental material often in combination with prepectoral implant placement is advertised. The present evidence on long-term outcome is limited.Super-microsurgery treating lymphedema is evolving rapidly. Refinements of various techniques and their differential indication are under evaluation to standardize the procedures.

SUMMARY

Breast reconstruction evolved to a complex, specialized field with a multitude of options. A multidisciplinary team is required to fully utilize todays potential and offer optimal individual treatments.

Surgical lymphology. Therapy option for lymphoedema and lipohyperplasia dolorosa

The typical therapy in lymphology is conservative. However, reconstructive and resective treatments for primary and secondary lymphoedema as well as resective procedures for lipohyperplasia dolorosa (LiDo) "lipedema" have been available for several decades. Each of these procedures has its clear indication and decades of successful history. These therapies represent a paradigm shift in lymphology. In reconstruction, the basic idea is to restore lymph flow, to bypass the obstacle to drainage in the vascular system. The combination procedures of two-stage application of resection and reconstruction in lymphoedema are just as much a "work in progress" as the concept of prophylactic lymphatic venous anastomosis (LVA). In the case of resective procedures, the focus is not only on improving the silhouette, but also on reducing the complex decongestion therapy (CDT) and - in the case of LiDo - freedom from pain by improving imaging procedures and the early use of surgical therapy options, the development of higher stages of lymphoedema should be a thing of the past. For LiDo, the application of surgical procedures avoids lifelong CDT and achieves painlessness. All surgical procedures, but especially the resection procedures, are now possible in a way that is gentle on the lymphatic vessels and should be offered to patients with lymphoedema or lipohyperplasia dolorosa without reservation if the goals - reduction in circumference, avoidance of lifelong CDT and, in the case of LiDo, painlessness - cannot be achieved by other means.

The Vicious Circle of Stasis, Inflammation, and Fibrosis in Lymphedema

SUMMARY

Lymphedema is a progressive disease of the lymphatic system arising from impaired lymphatic drainage, accumulation of interstitial fluid, and fibroadipose deposition. Secondary lymphedema resulting from cancer treatment is the most common form of the disease in developed countries, affecting 15% to 40% of patients with breast cancer after lymph node dissection. Despite recent advances in microsurgery, outcomes remain variable and, in some cases, inadequate. Thus, development of novel treatment strategies is an important goal. Research over the past decade suggests that lymphatic injury initiates a chronic inflammatory response that regulates the pathophysiology of lymphedema. T-cell inflammation plays a key role in this response. In this review, the authors highlight the cellular and molecular mechanisms of lymphedema and discuss promising preclinical therapies.

Fibroblast-Generated Extracellular Matrix Guides Anastomosis during Wound Healing in an Engineered Lymphatic Skin Flap

A healthy lymphatic system is required to return excess interstitial fluid back to the venous circulation. However, up to 49% of breast cancer survivors eventually develop breast cancer-related lymphedema due to lymphatic injuries from lymph node dissections or biopsies performed to treat cancer. While early-stage lymphedema can be ameliorated by manual lymph drainage, no cure exists for late-stage lymphedema when lymph vessels become completely dysfunctional. A viable late-stage treatment is the autotransplantation of functional lymphatic vessels. Here we report on a novel engineered lymphatic flap that may eventually replace the skin flaps used in vascularized lymph vessel transfers. The engineered flap mimics the lymphatic and dermal compartments of the skin by guiding multi-layered tissue organization of mesenchymal stem cells and lymphatic endothelial cells with an aligned decellularized fibroblast matrix. The construct was tested in a novel bilayered wound healing model and implanted into athymic nude rats. The in vitro model demonstrated capillary invasion into the wound gaps and deposition of extracellular matrix fibers, which may guide anastomosis and vascular integration of the graft during wound healing. The construct successfully anastomosed in vivo, forming chimeric vessels of human and rat cells. Overall, our flap replacement has high potential for treating lymphedema.

Combining reconstructive and ablative surgical treatment of chronic breast cancer-related lymphedema (BCRL): safe and effective

PURPOSE

We investigated whether a one-stage combination of vascularized lymph node transfer (VLNT) with water jet-assisted liposuction (WAL) can be safely performed and results in improved patient outcomes such as a greater reduction in arm volume when treating chronic breast cancer-related lymphedema (BCRL).

METHODS

In this retrospective cohort study, we included all patients from our encrypted lymphedema database treated for chronic BCRL with VLNT or VLNT + WAL who had a minimum follow-up of two years. We analyzed patient-specific variables including arm circumferences as well as patient-reported outcomes before and after surgery as well as surgery time, surgery-related complications and patient satisfaction.

RESULTS

Only the mean preoperative differences of the circumferences between the lymphedematous and the unaffected arm in individual patients showed a statistically significant difference between treatment groups (p < 0.05). Indeed, patients treated with VLNT + WAL had consistently larger differences in individual sets of arms and therefore more pronounced chronic BCRL. The mean surgery time was significantly longer in the VLNT + WAL group (p < 0.05). Complications were seldom and similar in both groups. Using a numeric rating scale, the level of patient satisfaction following treatment did not differ significantly between groups (p = 0.323).

CONCLUSIONS

Our findings suggest that a one-stage combination of VLNT with WAL does not result in more complications even though it also entails a longer surgery time. This is acceptable as secondary interventions resulting in overall longer surgery times and higher costs can be avoided. A one-stage combination might be especially favourable for patients suffering from more severe chronic BCRL.

Anatomy and relationships of forelimb lymph nodes in Sprague-Dawley rats: A detailed dissecting approach

Background

Constructing a reliable animal model for preclinical treatment of secondary lymphedema is challenging because the anatomical characteristics near the lymph nodes are understudied. Therefore, this study examined the detailed anatomical relationship between the axillary lymph node flaps (ALNFs) and brachial lymph node flaps (BLNFs) in the forelimb of Sprague-Dawley (SD) rats.

Materials and methods

Ten male rats, weighing 250–300 g, were used. The ALNFs and BLNFs on either side of the rat forelimbs were dissected. The two lymph node flaps (LNFs) were immediately harvested to analyze their physical characteristics (via imaging process software) and microscopic structure (via histology examinations).

Results

A total of 20 ALNFs and BLNFs from 10 rats were harvested and analyzed. ALNF dissection was simpler and lasted a shorter time than BLNF dissection (p < 0.0001). The left LNFs were more difficult to dissect than the right LNFs (p < 0.0001). In physical characteristics of LNFs, the area (p < 0.001) of LNFs and the number of lymph nodes (p < 0.0001) associated with ALNFs were greater than those associated with BLNFs, but the pedicle lengths of ALNFs were shorter than that of BLNFs (p < 0.0001). No significant difference in the diameter of the venous and arterial pedicles was noted between the two LNFs (p > 0.05).

Conclusion

This study reported detailed physical characteristics of ALNFs and BLNFs in SD rat forelimbs, assessing the respective area of LNFs, number of lymph nodes, and lengths and diameters of vascular pedicles. Moreover, this study suggested an efficient method to perform a study of LNFs by describing the operation process and repeatedly measuring the operation time.

Enhancing lymphangiogenesis and lymphatic drainage to vascularized lymph nodes with nanofibrillar collagen scaffolds

BACKGROUND

This study investigated the effect of nanofibrillar collagen scaffold (BioBridge) implantation from the affected limb to the unaffected contralateral femoral vein or lymph node in a rat model.

METHODS

Hind limb lymphedema in Lewis rats was created with lymphadenectomy and inguinal circumcision without radiation. The volumetric difference (greater than 5%) using computed tomography and indocyanine green fluorescence evaluated the progress of lymphedema at 4 weeks. The lymphedema rats have separated into Group I: Controls; Group II: implanted BioBridge to the contralateral femoral vein; and Group III: implanted BioBridge to the contralateral inguinal lymph node.

RESULTS

A total of 14 of 30 (46.7%) rats developed hind limb lymphedema with a mean volume difference of 5.83 ± 0.99% and showed diffuse dermal backflow at 4 weeks postlymphadenectomy. Four weeks postimplantation of BioBridge, the mean volumetric difference was 5.62 ± 2.11%, 4.97 ± 0.59%, and -2.47 ± 2.37% in Group I, II, and III, respectively (p < 0.05). The dermal backflow on the affected limb increased in Groups I and II but decreased in Group III.

CONCLUSIONS

Implantation of BioBridge from the affected limb to the contralateral inguinal lymph node significantly reduced the hind limb lymphedema at 4 weeks.

Vascularized Lymph Node Transfer Improved Outcomes of Elderly Patients with Secondary Upper Extremity Lymphedema

BACKGROUND

Secondary lymphedema is a debilitating morbidity. This study investigated the outcomes of vascularized lymph node transfer (VLNT) in elderly patients with secondary upper extremity lymphedema.

METHODS

Between 2008 and 2018, elderly (≥65 years) patients with secondary upper extremity lymphedema who underwent VLNT were retrospectively reviewed. Cheng's Lymphedema Grading, Taiwan Lymphoscintigraphy Staging, and indocyanine green lymphography were used to select the procedures. Outcome measurements included complications, circumferential difference, episodes of cellulitis, and the Lymphedema-Specific Quality of Life questionnaire (LYMQoL).

RESULTS

Eleven patients with a mean age of 70.2 ± 5.3 years (range 65-80 years) who underwent VLNT survived and no major complications were encountered. At a mean follow-up of 6.5 ± 3.6 years (range 2-13 years), the mean limb circumferential difference was significantly improved from 25.6 ± 11.5% to 8.3 ± 4.2% (p = 0.016), and the mean episode of cellulitis was statistically reduced from 2.4 ± 1.3 to 0.4 ± 0.9 times/year (p = 0.007). At a follow-up of 24 months, four domains of Function (from 30.6 ± 2.8 to 14.5 ± 2.5), Appearance (from 18.2 ± 1.9 to 8.5 ± 2.1), Symptoms (from 30.4 ± 5.9 to 10.9 ± 1.0) and Mood (from 29.2 ± 4.4 to 10.7 ± 1.0), as well as overall LYMQoL score (from 3.9 ± 1.1 to 7.4 ± 0.5), showed statistical improvement (all p < 0.05).

CONCLUSIONS

VLNT for secondary upper extremity lymphedema in elderly patients significantly decreased the limb circumferential difference and frequency of cellulitis and improved quality of life without using compression garments postoperatively.

Long-term outcomes of arterial ischemia or venous occlusion on vascularized groin lymph nodes in a rat model

BACKGROUND

This study investigated the long-term effects of arterial ischemia and venous occlusion on lymph node drainage function in a rat model.

METHODS

Bilateral groin lymph node flaps of 18 Lewis rats were dissected. The pedicle artery was clamped for 4, 5, and 6 h (A4, A5, and A6 groups), and the vein for 3, 4, and 5 h (V3, V4, and V5 groups) in six flaps. At 4 weeks, the evaluations included gross morphomics, indocyanine green (ICG) lymphography, histological section, immunofluorescence of terminal deoxynucleotidyl transferase assay, and heme oxygenase-1 (HO-1) stain.

RESULTS

The lymph node flaps developed shrinkage and partial necrosis in A5, A6, V4, and V5 groups. Hemorrhage in the lymph node cortex and medulla was observed histologically in A5, A6, and V5 groups. ICG lymphography showed loss of lymphatic drainage function in 2 of 6 flaps in A6 and V5 groups. Cell death was shown partly in cortical follicles in A5 and V4 groups and completely in A6 and V5 groups. The HO-1 expression was statistically increased in A5 and V5 groups, respectively (p < 0.05).

CONCLUSIONS

The critical arterial ischemia and venous occlusion time were 4 h at 4 weeks of follow-up.

Synthetic hydrogels engineered to promote collecting lymphatic vessel sprouting

The lymphatic vasculature is an essential component of the body's circulation providing a network of vessels to return fluid and proteins from the tissue space to the blood, to facilitate immune ce-ll and antigen transport to lymph nodes, and to take up dietary lipid from the intestine. The development of biomaterial-based strategies to facilitate the growth of lymphatics either for regenerative purposes or as model system to study lymphatic biology is still in its nascent stages. In particular, platforms that encourage the sprouting and formation of lymphatic networks from collecting vessels are particularly underdeveloped. Through implementation of a modular, poly(ethylene glycol) (PEG)-based hydrogel, we explored the independent contributions of matrix elasticity, degradability, and adhesive peptide presentation on sprouting of implanted segments of rat lymphatic collecting vessels. An engineered hydrogel with 680 Pa elasticity, 2.0 mM RGD adhesive peptide, and full susceptibility to protease degradability produced the highest levels of sprouting relative to other physicochemical matrix properties. This engineered hydrogel was then utilized as a scaffold to facilitate the implantation of a donor vessel that functionally grafted into the host vasculature. This hydrogel provides a promising platform for facilitating lymphangiogenesis in vivo or as a means to understand the cellular mechanisms involved in the sprout process during collecting lymphatic vessel collateralization.

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.

Vascularized lymph node transfer for surgical treatments of upper versus lower extremity lymphedema

OBJECTIVE

The purpose of this study was to compare clinical outcomes after vascularized lymph node transfer (VLNT) for the treatment of lymphedema performed on the upper and lower extremities.

METHODS

Between April 2015 and January 2020, 71 patients with advanced-stage lymphedema, categorized as International Society of Lymphology late stage 2 or 3, who underwent VLNT in upper and lower extremities were included in this study. Thirty-seven and 34 patients underwent VLNT in upper and lower extremities, respectively. The circumference of the affected and unaffected extremities was measured at baseline, follow-up visits, and at the last visit. The circumference was measured in six places on the extremities, and the circumference and volume percent differences between the affected and unaffected extremities were calculated. First, we compared preoperative and postoperative extremity circumferences in the overall, upper, and lower extremity groups. Second, we compared circumference and volume percent differences between the affected and unaffected extremities calculated at the last visit to identify the degree of improvement by VLNT in the upper and lower extremity groups.

RESULTS

The results of the comparative analysis between the preoperative and postoperative extremity circumferences showed that all postoperative extremity circumferences measured at the last visit were decreased compared with the preoperative values in the overall, upper, and lower extremity groups. In the upper extremity group, the circumference percent difference measured at the elbow was 23.1% before surgery and decreased to 13.4% at the last visit (P < .001). In the lower extremity group, the circumference percent difference measured at the knee was 24.4% before surgery and decreased to 17.4% at the last visit (P = .003). In the results of comparative analysis between the upper and lower extremity groups, there was a statistically significant difference in the postoperative circumference percent differences at the elbow/knee calculated at the last visit (P = .048). Similarly, there were statistically significant differences in circumference percent differences in two of six measurement sites at the last visit between the upper and lower extremity groups. However, there was no statistically significant difference in the volume percent difference calculated at the last visit between the upper and lower extremity groups.

CONCLUSIONS

These results demonstrate that VLNT may be effective in treating patients with advanced-stage lymphedema. However, patients with upper extremity lymphedema demonstrate superior outcomes compared with those with lower extremity lymphedema.

Where does subcutaneous lymph from the chest wall flow into after mastectomy?

BACKGROUND

Changes of the lymph flow from the chest wall after mastectomy and sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (Ax) has yet to be understood. This study aimed to investigate the effect of axillary surgery on lymphatic flow from the chest wall in patients who have undergone mastectomy, including those have undergone breast reconstruction and vascularized lymph node transfer (VLNT).

METHODS

Following mastectomy in 100 breasts, the directions of lymph flow from the chest wall was compared between the SLNB omission, SLNB, Ax, and Ax followed by VLNT groups using indocyanine green (ICG) lymphography in cross-sectional study. Lymph flow on the deep epigastric artery perforator (DIEP) flap was also investigated.

RESULTS

Lymph flow directing to the ipsilateral axilla was observed more frequently after SLNB than Ax (48% vs. 12.5%; p = 0.005); however, no significant difference was observed in the frequency of contralateral axillary route adoption between them (8% vs. 15%; p = 0.65). In the VLNT group, lymph flow to the ipsilateral axilla was not observed at a significantly higher frequency than in the Ax group (12.5% vs. 12.5%, p = 1.00). On the transferred DIEP flap, the lymph flowed anterograde or retrograde parallel to the anatomic course of the lymphatic vessels.

CONCLUSION

To visualize the direction of lymph flow of the chest following mastectomy, ICG lymphography may be useful to discern the direction in which malignant neoplasms, including lymphoma, are transported and to plan for lymph flow restoration.

The deep inferior epigastric lymphatic cable flap connected to gastroepiploic lymph node flap for treatment of refractory chylous ascites: Report of two cases

Chylous ascites is the leakage of lipid-rich lymph into the peritoneal cavity usually due to disruption of lymphatics or increased peritoneal lymphatic pressure. Various surgical options have been proposed to treat chylous ascites but most have shown suboptimal outcomes. The gastroepiploic vascularized lymph node (GE-VLN) flap has been described previously for the treatment of lymphedema. In chylous ascites, this flap could provide an alternate drainage pathway for the intraperitoneal chylous fluid. The purpose of this report is to present another option for the microsurgical treatment of refractory chylous ascites. Herein, we report two patients with refractory chylous ascites secondary to cancer who have undergone deep inferior epigastric-based lymphatic "cable" flap (DIE-LCF) connected to a pedicle GE-VLN flap. Patients were followed-up for a minimum of 2 years. Within the first 3 months following surgery, the patient's nutritional parameters improved along with drastic reduction of ascites. At 2 years follow-up postoperative abdominal circumference decreased significantly. None required further peritoneal paracentesis and all patients were free of chylous ascites symptoms. In conclusion, the DIE-LCF connected to a pedicle GE-VLN flap could be a feasible option for the microsurgical treatment of refractory chylous ascites.

From Bench to Bedside: The Role of a Multidisciplinary Approach to Treating Patients with Lymphedema

Background: Lymphedema is a condition characterized by dysfunction of the lymphatic system resulting in chronic, progressive soft tissue edema that can negatively impact individuals' function, self-image, and quality of life. Understanding of the disease process has evolved significantly in the past two decades with advances in diagnostic modalities and surgical techniques revolutionizing prior treatment algorithms. Methods and Results: We reviewed our current approach at the University of Southern California to improving outcomes in lymphedema treatment. Given the complexity of this medical condition, patients are best served by a multidisciplinary approach. At our institution, this involves a collaborative effort between bench researchers, lymphatic therapists, medical physicians, and lymphedema surgeons. Basic science and translational research provide further understanding into the underlying mechanisms of lymphangiogenesis and the possibility for potential therapeutic interventions. Our surgical algorithms require patients to undergo a thorough diagnostic evaluation and consultation with certified lymphatic therapists prior to undergoing either physiologic or debulking operations. Patients are followed clinically following any interventions. Further community outreach and education is carried out in order to improve upon early diagnosis and symptom recognition. Conclusions: Optimizing lymphedema care requires a collaborative interplay between researchers, physicians, and therapists. Additionally, patient and provider education on early disease recognition and treatment options is an equally critical aspect of improving patient outcomes.

Combined deep inferior epigastric artery perforator flap with vascularized groin lymph node transplant for treatment of breast cancer-related lymphedema

For survivors of breast cancer lymphedema is their greatest survivorship burden. Modern surgical techniques to treat lymphedema are effective at reducing limb volume, symptoms of lymphedema, episodes of cellulitis, and improving patient quality of life. Physiologic procedures, including lymphovenous bypass (LVB) and vascularized lymph node transplant (VLNT), restore physiological lymphatic function within the affected extremity. In patients with post-mastectomy breast cancer-related upper extremity lymphedema that desire breast reconstruction, microvascular abdominal flap breast reconstruction can be combined with superficial inguinal (groin) VLNT to provide breast reconstruction and treatment of lymphedema in a single operation. This article reviews the indications, preoperative assessment, surgical technique, outcomes, and tips and pearls for performing this procedure.

Technical Challenges in "Micro" Lymph Node Identification during Vascularized Submental Lymph Node Flap Harvesting

Background:

The outcome of autologous lymph node (LN) transfer has depended on the number of LNs in the donor site. Unknown accuracy of the LN counting method has thrown some doubts on the reliability of the previous statistics. This study aimed to assess the accuracy of naked eye (NK) and stereo microscopy (SM) as tools for LN count.

Methods:

In total, 40 vascularized submental LN flaps were harvested from 23 fresh cadavers. The colored polymer was injected into the external carotid arteries before the harvest. LNs in each flap were counted by NK, SM, and histology in sequential order.

Results:

An estimated 175 LNs were confirmed, 4.4 ± 1.8 per flap. NK sensitivity was 33.7% compared with that of SM at 63.5%. Both methods missed all micro-lymph nodes (micro-LNs), contributing to 5.1% (9 nodes) of all LNs. Non-LN structures (647 negative counts) were composed of fat lobules, salivary gland lobules, and muscle fibers. NK specificity was 98.0%, compared with that of SM at 96.1%. SM showed a higher false positive rate at 14.3%, compared with NK at 7.4%. False positive counts were located mostly in Ib sublevel.

Conclusions:

NK and SM are imperfect tools for LN count due to poor sensitivity. If the method needs to be applied, points of considerations are (1) undetectable micro-LNs, (2) interposition of LNs with the digastric muscle and submandibular salivary gland, (3) confusion of LNs with lobules of salivary gland supplied by glandular artery or fat lobules supplied by lobular artery.

Short-term molecular and cellular effects of ischemia/reperfusion on vascularized lymph node flaps in rats

Vascularized lymph node (VLN) transfer is an emerging strategy to re-establish lymphatic drainage in chronic lymphedema. However, the biological processes underlying lymph node integration remain elusive. This study introduces an experimental approach facilitating the analysis of short-term molecular and cellular effects of ischemia/reperfusion on VLN flaps. Lymph node flaps were dissected pedicled on the lateral thoracic vessels in 44 Lewis rats. VLN flaps were exposed to 45 or 120 minutes ischemia by in situ clamping of the vascular pedicle with subsequent reperfusion for 24 hours. Flaps not exposed to ischemia/reperfusion served as controls. Lymph nodes and the perinodal adipose tissue were separately analyzed by Western blot for the expression of lymphangiogenic and angiogenic growth factors. Moreover, morphology, microvessel density, proliferation, apoptosis and immune cell infiltration of VLN flaps were further assessed by histology and immunohistochemistry. Ischemia for 120 minutes was associated with a markedly reduced cellularity of lymph nodes but not of the perinodal adipose tissue. In line with this, ischemic lymph nodes exhibited a significantly lower microvessel density and an increased expression of VEGF-D and VEGF-A. However, VEGF-C expression was not upregulated. In contrast, analyses of the perinodal adipose tissue revealed a more subtle decrease of microvessel density, while only the expression of VEGF-D was increased. Moreover, after 120 minutes ischemia, lymph nodes but not the perinodal adipose tissue exhibited significantly higher numbers of proliferating and apoptotic cells as well as infiltrated macrophages and neutrophilic granulocytes compared with non-ischemic flaps. Taken together, lymph nodes of VLN flaps are highly susceptible to ischemia/reperfusion injury. In contrast, the perinodal adipose tissue is less prone to ischemia/reperfusion injury.

Morbidity of marginal mandibular nerve post vascularized submental lymph node flap transplantation

BACKGROUND

This study investigated the morbidity of the marginal mandibular nerve (MMN) post vascularized submental lymph node (VSLN) harvest.

METHODS

The VSLN with sacrifying or preserving the medial platysma was retrospectively classified as group I or II. Midline deviation and horizontal tilt were subjectively evaluated. Horizontal, vertical, and "area distribution" of the lower lip excursions of the surgical site were objectively compared with the nonsurgical site.

RESULTS

Seventeen patients in group I and 12 patients in group II were included. At a median follow-up of 48.6 ± 16.8 months in group I and 14.8 ± 7.5 months in group II, no MMN palsy was found in both groups. Median midline deviation and horizontal tilt were 4.53 ± 0.52 and 5 ± 0 in group I and 4.67 ± 0.65 and 5 ± 0 in group II, respectively (P = .419 and 1.000). Median horizontal, vertical and area of distribution of lower lip excursions were 97.5 ± 12.3%, 98.8 ± 14.4% and 87.2 ± 14.7% in group I, and 99.3 ± 15.1%, 95.8 ± 8.2% and 84.2 ± 14.2% in group II, respectively (P = .679, .948 and .711).

CONCLUSION

The VSLN flap was a safe procedure with minimal MMN morbidity.

Therapeutic Potential of Mesenchymal Stem Cells for Postmastectomy Lymphedema: A Literature Review

Upper limb lymphedema is one of the most common complications after breast cancer surgery and radiotherapy. Despite various physical therapy and surgical options available, the impaired lymph fluid drainage may be progressive due to lymphatic vascular insufficiency making treatment more difficulty. Stem cell therapy provides a promising alternative in the treatment of various chronic diseases. The wide applicability of cell therapy has been reviewed throughout literature. This review provides an overview of recent progress in the therapeutic effect of adult stem cells for primary and secondary lymphedema after breast surgery in preclinical studies and clinical cases. We start with a brief introduction about the pathophysiological mechanisms of postmastectomy lymphedema. Regarding existing treatments, we systematically summarize the benefits and limitations of recent progress. Because of their multidirectional differentiation potential and growth factor secretion, stem cell therapy shows promising results in the management of light to severe lymphedema. Increasing evidences have demonstrated a noticeable reduction in postmastectomy lymphedema and increased lymph-angiogenesis after specific stem cell therapy. Current data suggests that stem cell therapy in lymphedema treatment provides reversal of pathological reorganization associated with lymphedema progression. Finally, we propose potential strategies for overcoming the challenges in the development of multipotent progenitor cells for the treatment and prevention of lymphedema in clinical practice.

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.

Volumetric Differences in the Suprafascial and Subfascial Compartments of Patients with Secondary Unilateral Lower Limb Lymphedema

BACKGROUND

The subfascial compartment (deep to the deep fascia) in extremity lymphedema has not been evaluated. This study investigated the volumetric differences between the suprafascial and subfascial compartments of patients with unilateral lower extremity lymphedema.

METHODS

Thirty-two female patients with unilateral lower extremity lymphedema were enrolled, with eight patients in each of Cheng lymphedema grades I to IV. The volumes of the suprafascial and subfascial compartments were calculated after manually drawing the region of interest on computed tomographic images. The volumetric differences and their ratios in the suprafascial and subfascial compartments between each patient's bilateral limbs were compared.

RESULTS

The volume of the lymphedematous limbs (9647 ml) was significantly greater than the volume of unaffected limbs (6906 ml), with a median volumetric difference of 2097 ml (30.6 percent) (p < 0.01). The median suprafascial compartment volumetric difference was 1887 ml (56.6 percent) and the subfascial compartment volumetric difference was 208 ml (4.7 percent) (p < 0.01). The median volumetric difference ratio of the thigh and lower leg was 24.6 percent and 40.6 percent, respectively. The median volumetric differences in Cheng lymphedema grades I to IV were 1012, 1787, 2434, and 4107 ml, respectively, which were statistically significant among the four Cheng lymphedema grades using the Kruskal-Wallis test (p < 0.01).

CONCLUSIONS

The volumetric differences in the lymphedematous limb were statistically significantly greater than in the unaffected limb, including both suprafascial and subfascial compartments. The volumetric differences are consistent with the Cheng lymphedema grading system as a reliable indicator of unilateral extremity lymphedema.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, IV.

Simultaneous Ipsilateral Vascularized Lymph Node Transplantation and Contralateral Lymphovenous Anastomosis in Bilateral Extremity Lymphedema with Different Severities

Background

Extremity lymphedema can occur bilaterally with different severities on each side. The aim of this study is to investigate the treatment outcomes of such patients with bilateral extremity lymphedema of different severities.

Patients and Methods

Between 2013 and 2017, patients with bilateral extremity lymphedema of different severities according to the Taiwan Lymphoscintigraphy Staging (TLS) system were retrospectively reviewed. Ipsilateral vascularized lymph node transplantation (VLNT) was indicated in TLS total obstruction and contralateral lymphovenous anastomosis (LVA) in TLS partial obstruction with patent lymphatic vessels on indocyanine green lymphography. Outcomes were assessed using circumference improvement, frequency of cellulitis, and lymphedema-specific quality of life (LYMQoL) questionnaires.

Results

A total of 10 patients with bilateral extremity lymphedema with median age of 63 (range 12–75) years were included. The median symptom duration of the lymphedematous limb was 60 (range 36–168) months and 12 (range 1–60) months in the VLNT and LVA group, respectively (p < 0.05). At average follow-up of 37.5 (range 14–58) months, the average limb circumference improvement was 2.4 (range − 3.3 to 7.8) cm in the VLNT group and 2.3 (range 0.3–7) cm in the LVA group (p = 1). The median episodes of cellulitis decreased significantly from 4 to 0.5 and 1 to 0 times/year in the VLNT and LVA group, respectively (p = 0.02, p = 0.06). The overall LYMQoL score improved from 4.5 preoperatively to 7.5 postoperatively (p < 0.01).

Conclusions

Limb-specific VLNT and LVA selected by TLS effectively treated bilateral extremity lymphedema with different severities.

Surgical treatment of lymphedema

Lymphedema is a debilitating and progressive condition, which results in the accumulation of lymphatic fluid within the interstitial compartments of tissues and hypertrophy of adipose tissue due to the impairment of lymphatic circulation. The mainstay of current lymphedema treatment is nonsurgical management such as complex decongestive therapy and compression therapy. Recently, surgical treatment of lymphedema based on microsurgery has been developed to enable the functional recovery of lymphatic drainage and has complemented nonsurgical treatment. Lymphaticovenular anastomosis and vascularized lymph node transfer are representative physiologic surgeries in the treatment of lymphedema. Lymphaticovenular anastomosis is conducted to drain lymphatic fluid from obstructed lymphatic vessels to the venous circulation through surgically created lymphaticovenous shunts. Vascularized lymph node transfer involves harvesting lymph nodes with their vascular supply and transferring this vascularized tissue to the lymphedema lesion as a free flap. In addition to physiologic surgeries, ablative surgeries such as direct excision and liposuction also can be performed, especially for end-stage cases. Indications for surgical treatment vary across institutions. It is important not to delay physiologic surgery in mild to moderate cases of lymphedema.

Controversies in Surgical Management of Lymphedema

Surgical treatment of lymphedema has expanded in recent years. Lymphovenous bypass and vascularized lymph node transfer are both modern techniques to address the physiologic dysfunction associated with secondary lymphedema. While efficacy of both techniques has been demonstrated in numerous studies, there are several questions that remain. Here, the authors discuss the most pertinent controversies in our practice as well as the current state of surgical management of lymphedema.

Staging and clinical correlations of lymphoscintigraphy for unilateral gynecological cancer-related lymphedema

BACKGROUND

This study was to investigate the lymphoscintigraphy findings for the diagnosis and severity in unilateral gynecological cancer-related lymphedema (GCRL) and to correlate lymphoscintigraphy stages with the clinical findings.

METHODS

Patients with unilateral GCRL who underwent lymphoscintigraphy were staged using the presence of ileo-inguinal lymph nodes, distal-lymphatic ducts, and dermal backflow findings. Taiwan Lymphoscintigraphy Staging (TLS) was divided into three patterns and seven stages: normal drainage (L-0); partial obstruction (P-1, P-2, and P-3); and total obstruction (T4, T-5, and T-6). Correlations between clinical lymphedema severity and TLS were evaluated using analysis of variance and multivariable linear regression analyses.

RESULTS

A total of 141 patients with unilateral GCRL were divided as follows: 6 (4.3%) in normal drainage, 56 (39.7%) in partial-obstruction, and 79 (56%) in total obstruction. Cellulitis episodes, circumferential difference, and computed tomography (CT) volumetric difference were shown to be statistically different between TLS stages (P < .001 for all). Total obstruction stages were the most significant factors associated with the severity of circumferential difference (β = 19.72, 25.54, 32.42, respectively; P < .05) and CT volumetric difference (β = 36.04, 45.12, 52.78, respectively; P < .01).

CONCLUSIONS

Total lymphatic obstruction was present in 56% of unilateral GCGL. Lymphoscintigraphy stages were statistically correlated with episodes of cellulitis, circumferential difference and CT volumetric difference in unilateral GCRL.

Efficacy validation of a lymphatic drainage device for lymphedema drainage in a rat model

BACKGROUND

Vascularized lymph node transfer (VLNT) is an effective surgery for extremity lymphedema. This study evaluated a lymphatic drainage device (LDD) for the drainage of accumulated fluid into the venous system.

METHODS

Micropore filtering membranes with pore sizes of 5, 0.65, and 0.22 μm polyvinylidene difluoride, and 0.8 μm Nylon Net Filter were evaluated to determine the in vitro efficiency of drainage flow of an LDD. The two superior membranes were further used for the evaluation of the inflow and outflow of the LDD in vivo using 5% albumin.

RESULTS

At 5 minutes, the volumes drained with 5, 0.65, and 0.22 μm polyvinylidene difluoride and 0.8 μm nylon membranes were 15.2, 2.77, 2.37, and 0.59 mL, respectively (P < .01). At 10 minutes, the collected volumes of 5 and 0.65 μm polyvinylidene difluoride were 1788 and 1051 μL (P = .3). The indocyanine green fluorescence was detected at 50 seconds for the 5 μm polyvinylidene difluoride membrane but not for the 0.65 μm membrane.

CONCLUSIONS

The study successfully demonstrated the proof-of-concept of the LDD prototype that mimicked VLNT with drainage of 5% albumin into the venous system in a rat model.

Validity of the Novel Taiwan Lymphoscintigraphy Staging and Correlation of Cheng Lymphedema Grading for Unilateral Extremity Lymphedema

OBJECTIVE

The aim was to validate the new Taiwan Lymphoscintigraphy Staging, correlate it with Cheng Lymphedema Grading (CLG) and evaluate the treatment outcomes of unilateral extremity lymphedema.

BACKGROUND

No consensus has been reached for diagnosis and staging for patients with lymphedema among medical specialties.

METHODS

We included 285 patients with unilateral extremity lymphedema using lymphoscintigraphy. Lymphoscintigraphy was correlated to clinical symptoms and signs, and classified into normal lymphatic drainage, partial obstruction, and total obstruction. Inter- and intraobserver reliability of Taiwan Lymphoscintigraphy Staging, correlation between Taiwan Lymphoscintigraphy Staging and clinical findings were conducted. Patients were categorized in "surgical" (n = 154) or "nonsurgical" (n = 131) groups for outcome evaluation.

RESULTS

Lymphoscintigraphy found 11 patients (3.9%) with normal lymphatic drainage, 128 (44.9%) with partial obstruction, and 146 (51.2%) with total obstruction. Taiwan Lymphoscintigraphy Staging showed high interobserver agreement [intraclass correlation coefficient: 0.89 (95% confidence interval, 0.82-0.94)], and significantly correlated to computed tomography volumetric difference (r = 0.66, P < 0.001) and CLG [intraclass correlation coefficient: 0.79 (95% confidence interval 0.72-0.84)]. At a mean follow-up of 31.2 ± 2.9 months, significant improvement in the circumferential difference (from 23.9% ± 17.6% to 14.6% ± 11.1%; P = 0.03) with a mean circumferential reduction rate of 40.4% ± 4.5% was found in surgical group. At a mean follow-up of 26.6 ± 8.7 months, the nonsurgical group had increase of mean circumferential difference from 24.0% ± 17.2% to 25.3% ± 19.0% (P = 0.09), with a mean circumferential reduction rate was -1.9% ± 13.0%.

CONCLUSIONS

The Taiwan Lymphoscintigraphy Staging is a reliable diagnostic tool, correlated with clinical findings and CLG, aiding in the selection of the appropriate treatment to achieve favorable long-term outcomes in unilateral extremity lymphedema.

Intra-abdominal chylovenous bypass treats retroperitoneal lymphangiomatosis

BACKGROUND

Retroperitoneal lymphangiomatosis (RL) is a rare form of primary lymphedema featuring aberrant retroperitoneal lymphatic proliferation. It causes recurrent cellulitis, repeated interventions, and poor life quality. This study aimed to investigate proper diagnositc criteria and surgical outcomes for RL with extremity lymphedema.

METHODS

Between 2012 and 2018, 44 primary lower-extremity lymphedema cases received lymphoscintigraphy, magnetic resonance imaging, and single-photon electron computed tomography to detect RL. RL patients underwent vascularized lymph node transfers (VLNT) for extremity lymphedema and intra-abdominal side-to-end chylovenous bypasses (CVB) for chylous ascites. Complications, CVB patency, and quality of life were evaluated postoperatively.

RESULTS

Six RL patients (mean age of 30.3 years) had chylous ascites with five had lower-extremity lymphedema. All CVBs remained patent, though one required re-anastomosis, giving a 100% patency rate. Four unilateral and one bilateral extremity lymphedema underwent six VLNTs with 100% flap survival. Patients reported improved quality of life (P = 0.023), decreased cellulitis incidence (P = 0.041), and improved mean lymphedema circumference (P = 0.043). All patients resumed a normal diet and activity.

CONCLUSIONS

Evaluating primary lower-extremity lymphedema patients with MRI and SPECT could reveal a 13.6% prevalence of RL and guide treatment of refractory extremity lymphedema. Intra-abdominal CVB with VLNT effectively treated RL with chylous ascites and extremity lymphedema.

Delayed primary retention suture for inset of vascularized submental lymph node flap for lower extremity lymphedema

BACKGROUND

Vascularized lymph node transfer (VLNT) has become one of the effective surgical treatments for extremity lymphedema. This study was to evaluate the re-exploration and total complication rates of VLNT for lower extremity lymphedema between two different flap inset techniques.

METHODS

Sixty-nine patients who underwent 74 submental VLNT transfers between 2008 and 2018 were retrospectively studied. Fifty-six flaps were inset using a new delayed primary retention suture (DPRS) technique and other 18 flaps using conventional interrupted sutures as the non-DPRS group.

RESULTS

The overall flap success rate was 100%. The DPRS group was released at a mean of 1.7  ± 0.7 times and took a mean of 10.3 ± 3.3 days for wound closure. There were no statistical differences in demographics, mean symptom duration, and mean Cheng's Lymphedema Grading between two groups. Mean frequency of cellulitis of 2.5 ± 1.5 times/year in non-DPRS group was significantly greater than 1.4 ± 1.6 times/year in DPRS group (P = .01). The re-exploration and total complication rates were 5.4% and 7.1% in DPRS group, and 27.8% and 33.3% in non-DPRS group, respectively (P = .02 and .02, respectively).

CONCLUSIONS

The DPRS technique is a safe, simple, and reliable method for insetting the submental VLNT, which statistically decreased the re-exploration and total complication rates.

Long-term outcome of lower extremity lymphedema treated with vascularized lymph node flap transfer with or without venous complications

BACKGROUND

Vascularized submental lymph node (VSLN) transfer is an emerging approach for extremity lymphedema. This study investigated the long-term outcome and venous complications of VSLN for unilateral lower extremity lymphedema.

METHODS

Between 2010 and 2018, patients who underwent VSLN for unilateral lower extremity lymphedema were retrospectively evaluated. Patient demographics, operative records, complications, circumferential improvement, and episodes of cellulitis were analyzed. Further comparisons were performed between different types, numbers, and techniques of venous anastomoses.

RESULTS

A total of 75 VSLNs in 70 patients survived, giving a 100% success rate. Six flaps (8%) had venous complications (VC group) and 69 flaps (92%) did not (No-VC group). There were no statistical differences in types, numbers, and techniques of anastomoses between two groups (P = .65, 1, and .56, respectively). At a mean follow-up of 32.0 ± 23.0 months, mean circumferential improvement and episodes of cellulitis between two groups did not statistically differ significantly (P = .31 and .09, respectively).

CONCLUSIONS

VSLN is an effective treatment for lower extremity lymphedema. The types, numbers of veins, and techniques of venous anastomoses did not statistically affect the venous complication rates. Functional outcomes of the VSLNs were not compromised if venous complications were salvaged promptly.

Lymphoscintigraphy for the diagnosis of extremity lymphedema: Current controversies regarding protocol, interpretation, and clinical application

Appropriate diagnosis, staging and a further selection of the best treatment are fundamental for the management of patients with extremity lymphedema. Several clinical and imaging tools have been described for these purposes. Lymphoscintigraphy is still considered the gold standard imaging modality for diagnosing lymphedema. However, protocol variability and poor image resolution can make the interpretation challenging. Here, we reviewed technical aspects of lymphoscintigraphy, interpretation of the lymphoscintigraphy findings, staging, and its clinical application.

Effectiveness of Vascularized Lymph Node Transfer for Extremity Lymphedema Using Volumetric and Circumferential Differences

Background

Circumferential difference of lymphedematous limbs at designated anatomic distances has been the primary mode for measuring lymphedematous extremities. Computed tomography (CT) imaging produces accurate, consistent, hygienic volume measurements and a direct limb representation. This study compares these 2 main modalities and assesses their correlation.

Methods

CT and circumferential difference measurements, costs, and correlation of patient limbs that received vascularized lymph node transfer were compared.

Results

Mean circumferential difference by tape measurement pre- and postoperatively was 31.4% ± 19.1% and 17.4% ± 8.8% for upper limbs and 43.2% ± 16.1% and 22.4% ± 12% for the lower limbs, respectively. Mean CT volumetric difference pre- and postoperatively were 36.1 ± 4.1% and 27.2 ± 2.8% for the upper limb and 46.2 ± 3.2% and 33.2 ± 2.1% for the lower limbs, respectively. CT volume measurements significantly correlated with their respective circumferential difference with Pearson correlation coefficient of r = +0.7, which was statistically significant (P = 0.03), indicating a strong positive correlation between circumferential difference and actual limb volume changes as determined by CT imaging. Circumferential differences are more cost effective than CT volume assessments in the domains of measurement frequency (P = 0.03), fee (P < 0.01), time (P = 0.03), total cost per year (P < 0.01), and cost/minute (P = 0.03).

Conclusions

Standardized circumferential differences that are currently used are comparable to unbiased CT volumetric measurements and can be used as a reliable, reproducible, minimally invasive, low cost, and accurate method of measuring the lymphedematous limbs.

The Lymph Node Content of Supraclavicular Lymph Node Flap: A Histological Study on Fresh Human Specimens

Introduction: Vascularized lymph node transfer (VLNT) has become the established treatment for secondary lymphedema. The proposed mechanisms of VLNT include lymphangiogenesis and absorptive action of transplanted lymphatic tissue. Therefore, in theory, the lymph node content of lymph node flap is crucial to clinical response. The supraclavicular lymph node flap (SCLNF) has been described as one of the flap options for VLNT. However, its lymph node content has not been fully studied. The aim of this study is to find out the lymph node content of SCLNF with histological examination. Methods: Patients who required radical neck dissection or modified radical neck dissection due to cervical lymph node metastasis from head and neck cancer were included in this study. The SCLNF harvesting was performed as the first part of neck dissection. After flap harvesting, neck dissection was continued. The fresh SCLNF specimens were then sent for histological study. Results: Twelve SCLNFs were studied. The mean age of patients was 67.5 (range, 54-84) years. There were 10 males and 2 females. Seven flaps were harvested from the left side of neck, while five flaps were harvested from the right side of neck. The mean width, height, and thickness of SCLNF were 5.9 ± 0.6, 4.0 ± 0.5, and 1.8 ± 0.2 cm, respectively. The mean number of lymph nodes per flap was 8 ± 4.7 (range, 3-15). Conclusion: The lymph node content of SCLNF was confirmed. Its lymph node content is comparable to other lymph node flaps used in VLNT.

Correlation between Quantity of Transferred Lymph Nodes and Outcome in Vascularized Submental Lymph Node Flap Transfer for Lower Limb Lymphedema

BACKGROUND

Vascularized lymph node transfer has shown promising results in the treatment of lower limb lymphedema, but little is known about the number of lymph nodes needed for the transfer to achieve optimal results. This study investigated the correlation between number of transferred lymph nodes in submental vascularized lymph node transfer and outcomes regarding limb circumference reduction and cellulitis incidence.

METHODS

Thirty-five patients who had received vascularized submental lymph node transfer to an ankle for lower limb lymphedema following gynecologic cancer treatment were included in the study. Limb circumference was determined by means of tape measurement preoperatively and postoperatively and was used to calculate the circumferential difference. Ultrasonography was performed postoperatively to determine the number of lymph nodes within the transferred flap. Patients were divided into groups A through C depending on the number of transferred lymph nodes: 1 or 2 (n = 10), 3 or 4 (n = 14), and 5 to 8 (n = 11), respectively.

RESULTS

The mean age of the patients was 60.0 ± 9.2 years. All flaps survived. The mean improvement of circumferential difference for the whole cohort was 19.8 ± 9.2 percent. Groups B and C both had significantly higher improvements in the circumferential difference than group A (p = 0.04 and p = 0.02, respectively), but when compared to each other, the difference was nonsignificant. All groups had significant reductions in the incidence of cellulitis postoperatively.

CONCLUSIONS

Submental vascularized lymph node transfer for lower limb lymphedema reduced the incidence of cellulitis, regardless of the number of transferred lymph nodes. The transfer of three or more lymph nodes provided significantly better outcome regarding limb circumference reduction than the transfer of two or fewer lymph nodes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Critical Ischemia Time, Perfusion, and Drainage Function of Vascularized Lymph Nodes

BACKGROUND

Vascularized lymph node transfer is a promising surgical treatment for lymphedema. This study investigated the effect of ischemia on the lymphatic drainage efficiency of vascularized lymph node flaps and the critical ischemia time of lymph nodes.

METHODS

Twenty-four lymph nodes containing groin flaps in 12 Sprague-Dawley rats were dissected. Clamping of the vascular pedicle was performed for 0, 1, 3, 5, 6, or 7 hours; then, each was allowed to reperfuse by means of the vascular pedicle for 1 hour. Perfusion and ischemic changes were assessed using indocyanine green lymphography; laser Doppler flowmetry; and histologic studies with associated lymphatic vessel endothelial hyaluronan receptor-1, CD68, 4',6-diamidino-2-phenylindole, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling, and glutathione assay stains.

RESULTS

The mean latency period of the groin lymph node flaps was 247 ± 67, 83 ± 15, 72 ± 42, 30 ± 18, and 245 ± 85 seconds in the 0-, 1-, 3-, 5-, and 6-hour groups, respectively. Perfusion detected by laser Doppler was 85.2 ± 14.5, 87.2 ± 36.7, 129.8 ± 33.7, 140.4 ± 148.5, 156.1 ± 91.4, and 41.2 ± 34.8 perfusion units at ischemia times of 0, 1, 3, 5, 6, and 7 hours, respectively. Cell damage measured by glutathione was 46.8 ± 10.2, 67.7 ± 14.2, 62.8 ± 15.4, 126.6 ± 5.9, 259.0 ± 70.3, and 109.1 ± 27.5 at ischemia times of 0, 1, 3, 5, 6, and 7 hours, respectively. Histologically, as ischemia time increased, hemorrhage and congestion became more severe.

CONCLUSIONS

The critical ischemia time of vascularized lymph nodes is 5 hours in the rodent animal model, verified by indocyanine green lymphatic fluid uptake, laser Doppler perfusion, and histologic assessments. Interestingly, lymphatic drainage and perfusion of vascularized lymph nodes were improved with an increased ischemia time before the critical 5 hours was reached.