SVEP1, also known as Polydom, is a large extracellular mosaic protein with functions in protein interactions and adhesion. Since Svep1 knockout animals show severe edema and lymphatic system malformations, the aim of this study is to evaluate the presence of SVEP1 variants in patients with lymphedema. We analyzed DNA from 246 lymphedema patients for variants in known lymphedema genes, 235 of whom tested negative and underwent a second testing for new candidate genes, including SVEP1, as reported here. We found three samples with rare heterozygous missense single-nucleotide variants in the SVEP1 gene. In one family, healthy members were found to carry the same variants and reported some subclinical edema. Based on our findings and a review of the literature, we propose SVEP1 as a candidate gene that should be sequenced in patients with lymphatic malformations, with or without lymphedema, in order to investigate and add evidence on its possible involvement in the development of lymphedema.
Lymphoceles are lymphatic fluid collections resulting from lymphatic vessel disruption after surgery or trauma. They are most often described following retroperitoneal surgeries such as cystectomies, prostatectomies, renal transplants, and gynecologic surgeries. Most lymphoceles are asymptomatic and resolve spontaneously without treatment. If persistent, they can become infected or exert mass effect on adjacent structures causing pain, urinary, or lower limb edema particularly for lymphoceles in the pelvis Symptomatic lymphoceles should be treated to relieve symptoms and prevent functional compromise of vital adjacent structures. Although surgery has been traditionally accepted as the gold standard treatment, advances in imaging and interventional technology allow for less invasive, percutaneous treatment. Available minimally invasive treatment options include percutaneous aspiration, catheter drainage, sclerotherapy, and lymphangiography with lymphatic embolization. A review of these treatment options and a suggested algorithm for managing lymphoceles is presented.
Microcystic lymphatic malformations as described in the international literature form a subgroup of low-flow congenital vascular malformations (VM) resulting from irregular embryological development. Microcystic lesions normally manifest as an accumulation of lymph- and blood-filled vesicles that, when externalized, cause skin maceration with consequent pain and potential infection resulting in the impairment of the patient's quality of life. There is no consensus on a standardized algorithm nor clear guidelines for successful treatment of this type of lymphatic malformation, and treatment options employed often result in ambivalent and transient outcomes with a high rate of recurrence. The topical formulation of tacrolimus is a well-known FDAapproved anti-T cell agent that was recently identified as a potent activator of ALK1, which is involved in several processes and functions including angiogenesis. We investigated if topical administration of tacrolimus may be an effective therapy for directly targeting cutaneous microcystic lymphatic malformations as a complement to systemic treatment. The study enrolled four patients with cutaneous microcystic lymphatic malformations: three male (ages: 13,15,18) and one female (age: 30). Two of the patients presented lesions on their backs, one patient on the left hand and one on the left lower limb. All four patients received treatment with topical tacrolimus 0.1% twice a day for 10 weeks on a previously selected area for application. Weekly clinical follow-ups were conducted along with close physician-patient contact. All patients displayed a satisfactory response after treatment. Lymphorrhea and bleeding were stopped in all cases and the esthetic aspect of lesions improved in two patients. To date, all patients presented no clinically significant changes to the size or extension of the lesion. Topical tacrolimus treatment is a promising and reasonable option for microcystic lymphatic malformations. Our results encourage further exploration in larger populations with the consideration that it is a safe and effective alternative or complementary therapy to systemic treatment.
Patients treated for breast cancer are at risk of developing breast cancer-related lymphedema (BCRL). A significant proportion of patients treated for breast cancer are opting to undergo a contralateral prophylactic mastectomy (CPM). Currently, it remains unclear as to whether the relative volume change (RVC) equation may be used as an alternative to the weight adjusted change (WAC) equation to quantify BCRL in patients who undergo CPM. In order to simplify BCRL screening, our cohort of patients who underwent a CPM (n=310) was matched by BMI to a subset of patients who underwent unilateral breast surgery (n=310). Arm volume measurements were obtained via an optoelectronic perometer preoperatively, postoperatively, and in the follow-up setting every 6-12 months. The correlation of ipsilateral RVC and WAC values for those who underwent bilateral surgery was calculated (r=0.60). Contralateral WAC values for patients in both cohorts were compared, and there was no significant difference between the two distributions in variance (p=0.446). The RVC equation shows potential to be used to quantify ipsilateral postoperative arm volume changes for patients who undergo a CPM. However, a larger trial in which RVC and WAC values are prospectively assessed is needed.
Secondary lower extremity lymphedema is a common complication of treatment for gynecological cancers. Conservative therapy plays an important role in the treatment of patients with secondary lower extremity lymphedema; in particular, complex decongestive therapy (CDT) has been recognized as an effective nonoperative technique for these patients. But CDT therapy for secondary lower extremity lymphedema remains a problem in China because this technique and its effectiveness have not achieved widespread use and popularity. Our goal was to assess effects of CDT in patients with secondary lower limb lymphedema after treatment for gynecological cancers. The retrospective study consisted of 60 patients who were treated with 20 sessions of CDT. Assessments included objective changes in limb circumference, degree of LE, imaging features, and incidence of erysipelas before and after CDT treatment. We found that CDT can effectively improve lymph stasis and promote backflow, and decrease circumference, interstitial fluid content, and incidence of erysipelas of lymphedematous lower limb. Our results demonstrate that CDT is an effective treatment method for patients with secondary lower limb lymphedema following treatment for gynecologic cancers. This technique should be more widely utilized and popularized in China to improve the quality of life of millions of patients with secondary lower limb lymphedema.
To determine the historical use and utility of various lymphatic imaging modalities in Noonan syndrome (NS) patients, we performed a comprehensive literature review by collecting the published medical imaging of NS lymphatic dysplasias. We correlated imaging findings with clinical phenotypes and treatment. Our analysis of lymphatic imaging modalities provides an algorithmic approach to imaging and patient care across the spectrum of NS developmental defects. A total of 54 NS cases have been published since 1975. Using the observations reported in 15 reviewed publications, an association was made between disruptions in central lymphatic flow and poor clinical presentations/outcomes in NS patients.
Surgical intervention and subsequent wound healing process are known to induce neo-lymphangiogenesis, but few studies have been reported to utilize this mechanism for lymphedema treatment. The aim of this study was to evaluate feasibility of subdermal dissection for neo-lymphangiogenesis induction (SDN) to treat lower extremity lymphedema (LEL). Medical records of secondary LEL patients who had undergone ICG lymphography and SDN procedure were reviewed. SDN was performed by dissecting fat tissues just below the dermis from the most proximal area showing dermal backflow through abdominal-toaxillary lymphatic pathways. Perioperative lymphedematous conditions were evaluated with lymphedema quality of life score (LeQOLiS) and LEL index. Seventeen female patients were included. SDN could be performed in 10 minutes on average without postoperative complication. Postoperative ICG lymphography showed new lymphatic pathways in 6 (35.3%) cases. Postoperative LeQOLiS ranged from 9 to 66, which was statistically lower than preoperative LeQOLiS (32.9 ± 19.2 vs. 36.6 ± 19.3, p = 0.048), whereas there was no statistically significant difference between pre- and post-operative LEL index (275.2 ± 23.3 vs. 270.5 ± 20.8, P = 0.073). Subdermal dissection, although its probability is not high, has a potential to induce neo-lymphangiogenesis. Further studies are required to improve and demonstrate efficacy of the procedure for new lymphatic pathway creation.

