Lymphedema: Pathophysiology and clinical manifestations

Lymphatic Function and Dysfunction in the Context of Sex Differences

Endothelial cells are the building blocks of the blood vascular system and exhibit well-characterized sexually dimorphic phenotypes with regard to chromosomal and hormonal sex, imparting innate genetic and physiological differences between male and female vascular systems and cardiovascular disease. However, even though females are predominantly affected by disorders of lymphatic vascular function, we lack a comprehensive understanding of the effects of sex and sex hormones on lymphatic growth, function, and dysfunction. Here, we attempt to comprehensively evaluate the current understanding of sex as a biological variable influencing lymphatic biology. We first focus on elucidating innate and fundamental differences between the sexes in lymphatic function and development. Next, we delve into lymphatic disease and explore the potential underpinnings toward bias prevalence in the female population. Lastly, we incorporate more broadly the role of the lymphatic system in sex-biased diseases such as cancer, cardiovascular disease, reproductive disorders, and autoimmune diseases to explore whether and how sex differences may influence lymphatic function in the context of these pathologies.

Correlation between patency and clinical improvement after lymphaticovenous anastomosis (LVA) in breast cancer-related lymphedema: 12-month follow-up

PURPOSE

Breast cancer-related lymphedema (BCRL) is caused by an interruption of the lymphatic system after breast cancer treatment. Lymphaticovenous anastomosis (LVA), by which one or more patent lymphatic collecting vessels are connected to subcutaneous veins, shows promising results. Postoperatively, the patency of these anastomosis can be evaluated; however, little is known concerning the long-term patency after LVA in patients with BCRL. The aim of this study was to analyse the long-term patency, quality of life (QoL) and arm circumference after LVA, and to explore differences between patent and non-patent anastomosis and its correlation with clinical improvement.

METHODS

Twenty-five patients underwent indocyanine green (ICG) lymphography, lymph ICF-questionnaire, and arm circumference measurement preoperatively and 12 months after the LVA procedure.

RESULTS

Seventy-six percent of the patients showed at least one patent anastomosis after 12 months. Quality of life according to the Lymph-ICF increased significantly (p < 0.000); however, arm circumference showed no significant decrease. Sixty-five percent discontinued wearing compression stockings. The patent anastomosis group, compared with the non-patent anastomosis group showed, without significance, more improvement in QoL, arm circumference, and discontinuation of compression stockings, as well as a lower rate of infections both pre- and postoperatively, a shorter duration of lymphedema preoperatively, and a higher rate of early lymphedema and ICG stage.

CONCLUSIONS

LVA showed an acceptable patency and positive correlation between a patent anastomosis and clinical improvement after 12 months. Further research with a larger study population is required to determine whether outcomes or patient characteristics significantly correlate with a patent anastomosis after LVA operation.

Pathophysiology of aged lymphatic vessels

Lymphatic vessels maintain body homeostasis by recirculation of fluid and cells. Cell senescence induces lymphatic dysfunction. Impaired contractile function is caused by low muscle cell investiture and decrease of nitric oxide in aged lymphatic collectors, leading to poor drainage of lymph. Aging-induced loss of endothelial glycocalyx and production of inflammatory cytokines increases permeability of lymphatic vessels. In addition, aging-associated basal activation of mast cells delays immune response. In this review, we summarize the structural and pathological changes of aged lymphatic vessels, and discuss the underlying molecular mechanisms.

Lymphatic and blood systems: Identical or fraternal twins?

Blood and lymphatic systems work in close collaboration to ensure their respective physiological functions. The lymphatic vessel network is being extensively studied, but has been overlooked as compared to the blood vasculature mainly due to the problematic discrimination of lymphatic vessels from the blood ones. This issue has been fortunately resolved in the past decade leading to the emergence of a huge amount of data in lymphatic biology revealing many shared features with the blood vasculature. However, this likeliness between the two vascular systems may lead to a simplistic view of lymphatics and a direct transcription of what is known for the blood system to the lymphatic one, thereby neglecting the lymphatic specificities. In this context, this review aims to clarify the main differences between the two vascular systems focusing on recently discovered lymphatic features.

An Important Tool in Lymphedema Management: Validation of Turkish Version of the Patient Benefit Index-Lymphedema

Background: The aim of this study was to investigate the Turkish adaptation, validity, and reliability of the Patient Benefit Index-Lymphedema (PBI-L) ensuring direct assessment of the benefit in patients with lymphedema (LE), lipedema, and lipolymphedema. Methods and Results: Eighty-one patients who were consulted for physiotherapy, whose diagnoses were LE, lipedema, and lipolymphedema, and who were treated or planned to be treated for these diagnoses, were included in this study. PBI-L was adapted to Turkish by considering the stages of the cultural adaptation process. Short Form-36 (SF-36) was applied for the validity of PBI-L. PBI-L was repeated after a 1-week interval for test-retest reliability. The mean age was 47.66 ± 14.23 years. The intraclass correlation coefficient (ICC) value was determined as 0.73 (p < 0.0001) for the total score. There was a moderate correlation between first (ICC = 0.63, p < 0.0001) and second subdimensions (ICC = 0.62, p < 0.0001). Cronbach's α values ranged between 0.83 and 0.89. Low correlations were found between total scores of PBI-L and mental health, physical function subdimensions of SF-36 (p < 0.05). The Kaiser Meyer Olkin value was 0.6, and it was found that the PBI-L was not consistent with factor analysis. Conclusion: The Turkish version of PBI-L is a valid and reliable tool in patients with LE, lipedema, and lipolymphedema. However, the reassessment validity of PBI-L would be suggested by using an LE-specific quality of life questionnaire.

Paraxial Mesoderm Is the Major Source of Lymphatic Endothelium

Endothelial cells (ECs), which line blood and lymphatic vessels, are generally described to come from the lateral plate mesoderm despite experimental evidence for a broader source of origin, including the paraxial mesoderm (PXM). Current dogma suggests that following specification from mesoderm, local environmental cues establish the distinct molecular and functional characteristics of ECs in different vascular beds. Here we present evidence to challenge this view, showing that lymphatic EC fate is imprinted during transition through the PXM lineage. We show that PXM-derived cells form the lymphatic endothelium of multiple organs and tissues, with a more restricted contribution to blood vessel endothelium. By deleting Prox1 specifically in PXM-derived cells, we show that this lineage is indispensable for lymphatic vessel development. Collectively, our data establish lineage history as a critical determinant of EC specialization, a finding with broad implications for our understanding of vascular development and heterogeneity.

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Lineage history is a key determinant of endothelial cell specialization

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Endothelial cells arising from paraxial mesoderm preferentially form lymphatic vessels

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Paraxial-mesoderm-derived endothelial cells are essential for lymphatic development

Lymphedema in patients with hidradenitis suppurativa: a systematic review of published literature

BACKGROUND

Lymphedema is a debilitating complication of hidradenitis suppurativa (HS) that can be therapeutically challenging. Systematic evaluation of the clinical presentation and management of this condition has yet to be performed.

METHODS

OVID MEDLINE and EMBASE databases were searched along with a review of the references of searched articles for all English reports discussing lymphedema secondary to HS.

RESULTS

Two case series and 15 case reports met inclusion criteria, representing 27 patients. On average, these patients had a history of HS for 18 years (range 4-30 years). Lymphedema was found in the following areas in order of frequency: scrotum (16 patients, 59%), penis (12 patients, 44%), labia majora (4 patients, 15%), perineum (3 patients, 11%), groin (3 patients, 11%), buttocks (2 patients, 7%), and abdomen (1 patient, 4%). In six patients (22%), lymphedema occurred in two or more of the aforementioned locations. Lymphedema most commonly presented not only as swelling with induration but also as verrucous papules or nodules. The majority of cases (14 patients, 52%) were treated with radical surgical excision combined with medical therapy and obtained favorable outcomes. Surgical defect was most frequently covered with split thickness skin grafts 7 patients, 54%) followed by skin flaps (3 patients, 11%) and healing by secondary intention (3 patients, 11%).

CONCLUSIONS

Lymphedema appears to be a relatively rare complication of chronic HS that most commonly affects the anogenital region. Based on the evidence available, dermatologists should pursue a collaborative approach with surgery in the management of this condition at early stages.

Bioelectrical impedance analysis; a new method to evaluate lymphoedema, fluid status, and tissue damage after gynaecological surgery - A systematic review

The aim of this descriptive review is to summarise the current knowledge of non-invasive bioelectrical impedance analysis (BIA) used with gynaecological surgical patients in regard to postoperative development of lymphoedema and determination of perioperative fluid balance, and as a prognostic factor in cancer mortality and a predictor of postoperative complications. The databases PubMed, MEDLINE, Scopus Web of Science, the Cochrane Library, and reference lists of selected articles were searched for relevant articles published during the period January 2008-April 2018. Only papers published in English were retrieved. Thirty-seven articles were evaluated. Where gynaecological studies were lacking, studies with a study population from neighbouring clinical fields were used instead. Studies on the clinical use of BIA with gynaecological surgical patients were divided into three categories: the postoperative development of lower limb lymphoedema (n = 7), perioperative hydration measuring (n = 3), and the BIA parameter phase angle as a prognostic factor in cancer survival and as predictive for postoperative complications (n = 6). Of these 16 studies only three used a pure gynaecological study population. Three different methods of BIA were used in these articles: single frequency-BIA, multifrequency-BIA and bioimpedance spectroscopy. BIA was found to detect lymphoedema with a sensitivity of 73% and a specificity of 84%. Studies indicated that BIA was able to detect lower limb lymphoedema at an early stage even before it became clinically detectable. During postoperative hydration measurements, an increase in extracellular fluid volume and extracellular fluid volume in relation to total body fluid volume, as well as a decrease in phase angle, were associated with higher frequencies of postoperative complications. Moreover, low values for the phase angle have been associated with increased mortality in cancer patients. However, the number of studies in this field was limited. From our review, BIA seems to be a useful tool for use in the clinical setting of the gynaecological surgical patient. The theoretical approach of using bioelectrical impedance values to measure the fluid distribution in the body compartments offers wide opportunities in the clinical setting. However, so far, all studies have set up cut-off limits within the study population, and reference values for a general population need to be defined. There are also rather few studies on a gynaecological study population. Hence, there is a need for further studies within gynaecological surgery focusing on early detection of lower limb lymphoedema, perioperative fluid balance, and postoperative complications in order to establish the value of BIA in clinical praxis.