Lymphatics

Background: Nodal dendritic cells (DCs) and CD169-positive macrophages, possibly monocyte-derived, cross-present cancer antigens earlier in the proximal node than in the distal node. Methods: We performed immunohistochemical and morphometric analyses to show differences in the distributions of DC-SIGN-, CD68-, and CD169-positive cells in the paratracheal, subcarinal, and hilar nodes from 25 non-small cell lung cancer patients without metastasis. Results: CD169-positive and DC-SIGN-positive cells were colocalized in the subcapsular and paracortical sinuses, whereas CD68-positive, self-renewal alveolar macrophages were present in the medullary sinus. This complementary distribution was more evident in nodes other than hilar nodes. In hilar nodes, the proportion of CD68-positive macrophages usually exceeds 50%. Notably, the proportion of the overlapped cluster between CD169-positive cells and DC-SIGN-positive cells, which likely corresponds to the cross-presentation activity, was almost the same between the hilar and “next-upstream” node (i.e., the paratracheal node for the upper lobe and the subcarinal node for the lower lobe). Monocyte-derived cells occupied a significantly larger area in the hilar nodes of patients with upper lobe cancer than in patients with lower lobe cancer (p = 0.002–0.009). Conclusion: The specific site occupying the lung hilum with collateral vessels seemed to determine the hilar node composite cells. Full article

The lymphatic system, a complex and dynamic network comprising lymphatic vessels, lymph nodes (LNs), and associated lymphoid tissues, plays a pivotal role in regulating interstitial fluid balance and providing immune surveillance across the body. In cancer, however, the lymphatic system often transforms into a pathway for malignant cell dissemination, leading to lymphatic metastasis—a significant step in tumor progression associated with worse patient prognoses. Mechanistically, tumor cells exploit lymphangiogenic pathways to facilitate their entry and spread within the lymphatic network. Key mechanisms in this process include the upregulation of vascular endothelial growth factors C and D (VEGF-C/D), which promote lymphatic endothelial proliferation, vessel dilation, and increased permeability. This review seeks to provide an in-depth examination of the biological mechanisms underpinning lymphatic metastasis, explore its impact on cancer progression, and highlight current and emerging strategies aimed at managing metastatic disease. Full article

B-type acute lymphoblastic leukemia (B-ALL) is the most common childhood cancer. Despite significant advancements in treatment, chemotherapy resistance and relapse remain major challenges to be overcome. Oxidative stress markers, including lipoperoxides, have emerged as potential biomarkers in B-ALL patients under treatment. This study evaluated lipoperoxide levels in the peripheral blood of pediatric B-ALL patients during the induction phase of chemotherapy using high-sensitivity chemiluminescence and analyzed their association with clinical prognostic factors and patient outcomes, including definitive hospital discharge, disease relapse, and patient death. Lower lipoperoxide levels were observed in patients over 10 years old, those who achieved remission and were discharged from the hospital, and those with central nervous system (CNS) involvement. In contrast, significantly higher lipoperoxide levels were found in patients who relapsed, died, or had platelet counts exceeding 50,000/mm³. Receiver operating characteristic (ROC) curve analysis suggests that lipoperoxides may serve as potential biomarkers during the induction phase of chemotherapy, distinguishing B-ALL patients undergoing treatment from those not in treatment (sensitivity: 92.31%; specificity: 71.43%). These findings highlight the potential utility of lipoperoxides as prognostic biomarkers in B-ALL patients. Full article

IgG4 is an unusual immunoglobulin (Ig) and is the least component of IgG in humans. It is often asymmetrical and heterobivalent with weak Fc (fragment crystallizable region)-dependent effector function and ineffective complement activation, thus playing an unclear role in immune functions. IgE is an uncommon Ig, being important mostly in allergy and type 2 immunity. There are two rare chronic Ig-related fibroinflammatory diseases, namely IgG4-related disease (IgG4RD) and Kimura disease (KD), characterized by prominent IgG4- or IgE-positive plasma cells in the affected tissues, with or without blood elevations of the same Ig. The etiology of these two Ig-related diseases is unclear, though it appears that the pathogenesis in both is related to polarized Ig heavy chain isotype switching, concomitant with other cellular, cytokine and chemotaxin interactions that culminates in the characteristic pathologic manifestations of inflammation and fibrosis. IgG4RD and KD, despite having overlapping and differing features, may be connected by the similar pathogenetic polarized Ig isotype switching. Full article

Disease eponyms can be confusing, difficult to remember, scientifically non-robust, and lacking in implications on and relationships with cell lineage, histogenesis, and pathogenesis. This review is geared toward revisiting hematolymphoid diseases with eponyms in light of recent advances in technology and science by searching the past fifty years of the literature using Scopus and Google Scholar with the keywords “eponyms, hematolymphoid, diseases, lymphoma, benign, malignant, lymph node, spleen, liver, bone marrow, leukemia”. With advances in science and technology, there is accumulation of information on the morphologic nuances and immunologic, immunophenotypic, and genetic features of various hematolymphoid eponymic diseases, thus shedding light on important issues of etiology and pathogenesis with implications on therapy in various non-neoplastic (Castleman, Evans syndrome Kikuchi–Fujimoto, IgG4-related diseases) and neoplastic (Hodgkin, Burkitt, NK/T-cell lymphomas, dendritic/histiocytic neoplasms, and Sezary syndrome) diseases. This contributes to modern nomenclature, classification, subtyping, prognostication, and discoveries on new treatment strategies of hematolymphoid eponymic diseases. Full article

The central conducting lymphatics (CCL) and mesenteric lymphatic systems are responsible for lipid absorption, fluid regulation, and protein delivery into the bloodstream. Disruptions in these systems can result in debilitating conditions such as chylothorax, plastic bronchitis, post-operative lymphocele, protein-losing enteropathy (PLE), and chylous ascites. Advances in imaging techniques, including magnetic resonance lymphangiography (MRL), computed tomography lymphangiography (CTL), and fluoroscopic lymphangiography, allow for detailed anatomic and functional evaluation of the lymphatic system, facilitating accurate diagnosis and intervention by interventional radiologists. This review explores the embryology, anatomy, and pathophysiology of the lymphatic system and discusses imaging modalities and interventional techniques employed to manage disorders of the conducting lymphatics in the chest and abdomen. Thoracic duct embolization (TDE), percutaneous transhepatic lymphatic embolization (PTLE), and sclerotherapy are highlighted as effective, minimally invasive approaches to treat lymphatic leaks and obstructions and have shown high success rates in reducing symptoms and improving patient outcomes, particularly when medical management fails. This review seeks to demonstrate how anatomical imaging can facilitate minimally invasive procedures to rectify disorders of lymphatic flow. Full article

The impaired repair of lymphatic vessels after tissue damage is an etiological hallmark of lymphedema. Previously, we demonstrated that lymphatic recanalization after the popliteal lymph node extirpation was delayed in Gata2 heterozygous mice. This impaired lymphatic vessel recanalization in Gata2 heterozygous mice was mitigated by administrating atelocollagen or crossing with heterozygous Gata3 deletion mice. To clarify the potential involvement of Gata3 heterozygosity in collagen gene expression within subdermal tissue, we conducted an RNAseq analysis and found 273 genes with up and 522 genes with down expression in Gata3 heterozygous mice, and these genes were categorized as collagen and extracellular matrix-related genes by GO analysis. We also found that Col6a1, a2, and a3, which compose type VI collagen, underwent a transient but significant upregulation during the lymphatic recanalization process. Histological analysis revealed that the collagen structure in the subdermal tissue exhibited thinner collagen fiber in Gata3 heterozygous deficient mice. These findings suggest that the altered collagen pattern in Gata3 heterozygous mice contributed to the enhanced lymphatic vessel recanalization in Gata2 heterozygous mice. The altered collagen expression pattern might play a role in shaping and maintaining the subcutaneous microenvironment. Full article

Background/Objectives: The prognosis of acute lymphoblastic leukemia has significantly improved with the incorporation of innovative therapies such as immunotherapy, tyrosine kinase inhibitors, and CAR-T cell-based treatments. Drug resistance, mediated by genes such as ABCB1, has been associated with reduced treatment efficacy in various clinical scenarios. Although measurable residual disease (MRD) is the most reliable tool for monitoring treatment response in acute lymphoblastic leukemia, the relationship between ABCB1 expression and MRD remains unclear. Aims: To evaluate the expression of the ABCB1 resistance gene and explore its potential relationship with measurable residual disease. Methods: Prospective cohort where 57 patients with de novo diagnosis of acute lymphoblastic leukemia were admitted to the Hospital General de México “Dr. Eduardo Liceaga” between 2022 and 2024. Results: A total of 57 patients undergoing chemotherapy-based treatment were included, with a majority being male (n = 30, 52.6%) and a mean age of 32 years (range 18–71 years). Analysis of ABCB1 gene expression revealed that 35.1% (n = 20) had low expression, 40.4% (n = 23) had overexpression, and 24.6% (n = 14) showed absent expression. No statistically significant association was identified between MRD positivity and the presence of the Philadelphia chromosome (p = 0.171, 95% CI) or the ABCB1 high-risk group (high or absent expression) (p = 0.538, 95% CI). Conclusions: Although ABCB1 expression remains a valuable tool for understanding drug resistance in acute lymphoblastic leukemia, this study did not identify a significant relationship with MRD. MRD continues to be the most reliable prognostic factor in chemotherapy-based treatments for acute lymphoblastic leukemia, underscoring its importance in personalized medicine. Full article

Post-transplant lymphoproliferative disorder (PTLD) is the most common malignancy in adults who receive solid organ transplantation (SOT), apart from skin cancer. It is a serious and potentially fatal complication of chronic immunosuppression (ISI) in SOT recipients. This report describes a 20-year (2001–2021) clinicopathological experience with 59 PTLD patients at an urban center. The median time from transplant to PTLD was 8.5 years and the most common types of transplants were kidney (41%) and liver (31%). Epstein–Barr encoding region (EBER) was positive in 51% tumors, and 50% patients had Epstein–Barr virus (EBV) viremia at diagnosis. Overall survival (OS) at 1 year and 5 years was 78% and 64%, respectively. OS was significantly (p < 0.05) shorter in males (hazard ratio [HR] 3.7), certain organ transplants (lung HR 10.4; liver HR 3.9 relative to kidney), PTLD diagnosed within 12 months of transplant (HR 4.1), multi-organ involvement at diagnosis (HR 7.1), vitamin D deficiency at diagnosis (HR 4.5), and low serum albumin level at diagnosis (HR 3.6). Our study highlights the prognostic factors of PTLD and corroborates improved PTLD outcomes in the past 20 years. Full article

Lymphatic malformations (LMs) are benign, congenital vascular anomalies caused by abnormal lymphangiogenesis during embryology, often presenting as fluid-filled cystic lesions. Though LMs can affect any part of the body except the brain, they primarily manifest in the head and neck or axilla regions of children. With a prevalence of approximately 1 in 4000 births, LMs are commonly diagnosed by age two, with symptoms varying based on lesion location and size. This paper reviews the classification of LMs and discusses the de Serres staging system, which aids in assessing prognosis based on lesion site. Mutations in the (PIK3CA) gene are implicated in most cases, and LMs are also associated with syndromic conditions like Turner and Noonan syndromes. They are diagnosed by ultrasound (USS) or magnetic resonance imaging (MRI), while a histologic analysis can confirm lymphatic origin. Treatment options range from conservative approaches, such as observation, to sclerotherapy, pharmacotherapy, and surgery. Sclerotherapy, particularly with agents like OK-432, bleomycin, and doxycycline, has shown significant efficacy in reducing LM size and symptoms with minimal side effects. Pharmacological therapies, such as sirolimus, that target the mTOR pathway are also increasingly being used, with a good effect on the burden of disease. While surgical excision remains a choice for symptomatic or large lesions, minimally invasive approaches are often preferred due to lower morbidity. Emerging techniques include gravity-dependent sclerotherapy, electrosclerotherapy, alpelisib, everolimus, and Wnt/β-catenin pathway stimulators (e.g., tankyrase inhibitors, porcupine inhibitors). Computational atomistic molecular dynamics (MD) and density functional tight binding (DFTB) techniques may offer an experimental approach to future therapeutic targets. This paper highlights a multidisciplinary approach to LM management, emphasising individualised treatment based on lesion characteristics and patient needs. Full article

Introduction: Studies on the association between immune-mediated disorders and lymphoid disorders have been very limited, especially in diverse populations. The objective of this study is to evaluate the relationship between a variety of immune diseases and lymphoid malignancies. Methods: The NIH “All of Us” database was utilized to perform a cross-sectional analysis between lymphoid disorders and various immune diseases. The adjusted multivariable logistic regression analysis was performed in R to examine the association between lymphoid disorders such as leukemia, lymphoma, and plasma cell neoplasms against a variety of autoimmune diseases. Results: In the study cohort of 316,044 patients, we found significant associations between lymphomas and the aforementioned immune-mediated diseases, with the exception of dermatomyositis and scleroderma. Lymphoid leukemias showed significant associations (p < 0.001) with several autoimmune conditions, including psoriasis, type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus, ulcerative colitis, and hyperthyroidism. In plasma cell neoplasms, significant associations were found in all but dermatomyositis, scleroderma, vitiligo, and atopic dermatitis (p < 0.001). Conclusions: In this population-level analysis, the majority of immune-mediated diseases were found to be significantly correlated with an increased incidence of lymphoid malignancies. As such, patients diagnosed with immune-mediated diseases should undergo close surveillance and early screening with the goal of early identification and treatment of lymphoid malignancies. Full article

Multiple myeloma is an incurable hematologic malignancy arising from plasma cells. The uncontrolled growth of monoclonal plasma cells leads to an abnormal overproduction of immunoglobulins. The recommended course of treatment for MM is according to disease progression and responses to therapeutic intervention, highlighting the necessity for multiple treatment options that alleviate different parts of MM. This comprehensive review provides insights into the current treatments and how to take preventative and prognostic measures. In advanced MM, osteoporosis is a common symptom that originates from a lack of regulation in osteoclast activity and bone resorption. Bisphosphonates such as zoledronic acid and pamidronate along with monoclonal antibodies such as denosumab hinder osteoclast function and aid in reducing the risk of fractures in patients with advanced MM. For targeted therapy approaches, proteasome inhibitors impede protein degradation pathways that cause an accumulation of misfolded proteins promoting cancer cell proliferation in patients with MM. CAR-T is another targeted therapy that can utilize T cells to target and isolate MM cells. Overall, this review highlights the frontrunners of treatments for those diagnosed with MM. Full article

The soluble interleukin-2 receptor (sIL-2R) is a novel biomarker associated with a variety of immune-mediated diseases. It is produced through the proteolytic cleavage of the membrane-bound interleukin-2 receptor α-chain on activated T lymphocytes; hence, its increase reflects T-cell activation and immune dysregulation. Elevated sIL-2R levels are frequently documented in conditions such as rheumatoid arthritis, systemic lupus erythematosus, sarcoidosis, relapsing polychondritis, histiocytosis, hemophagocytic lymphohistiocytosis, lymphomas, and graft-versus-host disease, suggesting a potential role in monitoring disease activity and progression. However, sIL-2R levels may increase in the context of immune response to infections and malignancies, requiring careful interpretation. It is essential to determine whether elevated levels of this marker within specific ranges could suggest a specific entity, due to the implications this may have for the management of patients. This case-based review presents five patients with different immune-mediated diseases, highlighting how these different conditions can present with characteristic ranges of sIL-2R elevation. By integrating clinical findings with sIL-2R measurements, we emphasize the biomarker’s utility in guiding diagnosis, as well as monitoring disease activity and determining prognosis, which can enhance clinical decision-making and patient management in rheumatology and related fields. Full article

The sentinel lymph node technique in early-stage cervical cancer—when to perform it, its process, as well as the surgical specimen—continues to be a challenge for gynecologists, oncologists, and pathologists in order to plan the therapeutic strategy. The objective of this paper is to describe the state of the art and provide a critical point of view about these topics. Full article

Anti-CD19 chimeric antigen receptor (CAR) T-cell and anti-CD20 bispecific antibody therapies (BsAbs) are rapidly moving to earlier treatment lines for patients with B-cell non-Hodgkin lymphoma (B-NHL). The rapid pace of the advancement of these T-cell-engaging therapies is juxtaposed by a lack of a comprehensive understanding of the scope and kinetics of immunodeficiency following these treatments. We review emerging studies detailing the safety and efficacy of CD19 CAR-T and CD20 BsAbs in earlier lines for B-NHL, as well as a discussion of the limited knowledge of immune recovery following these treatments. We integrate the limited consensus prevention and management recommendations, advocating that the management of secondary immunodeficiency following these transformative therapies is an urgent unmet need in immune oncology research. A collaboration between hematologists/oncologists and immunologists in the management of these patients is critical to optimize patient care. Full article

Lymphatic complications are becoming increasingly identified in cancer patients. Chylous ascites, chylothorax, lymphoceles, and lymphorrhea are common in cancer patients and can occur due to traumatic injury during surgeries or infiltrative effects of the tumors themselves. Recently, some anti-neoplastic medications are also thought to result in lymphatic complications. Management options range from conservative options to minimally invasive interventions, to surgical interventions with no standardized management strategy. Imaging techniques such as dynamic contrast-enhanced magnetic resonance lymphangiography and intranodal computed tomography or fluoroscopic lymphangiography are becoming more valuable in diagnosis and treatment planning. Minimally invasive interventions are rapidly evolving and have become the first-line intervention in most cases. Current research, however, faces limitations due to study design and variability. Standardized reporting and prospective studies are needed to advance the field. This review summarizes some of the latest literature on lymphatic interventions in cancer patients and provides reporting recommendations for future studies on lymphatic interventions. Full article

Lymphedema surgeries have been proven effective in treating lymphedema and are not considered experimental or unproven. The medical literature consistently supports the safe and successful use of physiologic drainage lymphedema surgeries such as lymphaticovenous anastomosis (LVA), vascularized lymph node transfer (VLNT), and reductive surgeries such as suction-assisted protein lipectomy (SAPL) when performed by an experienced lymphedema surgery team to treat properly selected patients. Proper integration of lymphedema therapy is critical to achieving successful outcomes. We review effective lymphedema surgeries, their indications, patient selection, and the proper application of surgical treatments to achieve optimal results. Full article

Inflammatory breast cancer (IBC) is characterized by numerous tumor emboli within lymphatics. In a recent study, we observed tumor embolic budding both in vitro and in vivo within lymphovascular spaces and proposed this to account for the plethora of tumor emboli seen in IBC. These observations did not address, however, how lymphovascular invasion is initiated or the mechanisms involved. In the present study, using the well-characterized patient-derived xenograft (PDX), Mary-X, which exhibited florid lymphovascular invasion (LVI) in athymic mice (LVI) as defined by E-cadherin-positive tumor emboli within lymphatic channels distinguished by podoplanin and LYVE1 membrane and Prox1 nuclear immunoreactivities and spontaneous spheroidgenesis in vitro and human cases of IBC which showed similar LVI, we compared laser-captured microdissected emboli from Mary-X and from the cases of human IBC to non-embolic areas. Mary-X and IBC emboli expressed high levels of E-cadherin and no evidence of epithelial–mesenchymal transition (EMT). Mary-X spheroids expressed high levels of VEGF, especially VEGF-C, and stimulated both vascular and lymphatic endothelial haptotaxis. We then transplanted Mary-X serially into green, cyano, red, and nestin-green fluorescing protein (GFP-, CFP-, RFP-, and nestin-GFP) transgenic reporter mice in various combinations. Multicolor murine imaging studies indicated that reporter-labeled stroma initially encircled clumps of tumor cells and then served as a scaffold that supported nestin-GFP-labeled endothelial haptotaxis resulting in encircling lymphangiogenesis, confirmed by dual LYVE1 immunofluorescence. The present studies demonstrate a possible mechanism of a critical step of the tumor emboli formation of IBC. Full article

Despite chronic fibrosis occurring in many pathological conditions, few in vitro studies examine how fibrosis impacts lymphatic endothelial cell (LEC) behavior. This study examined stiffening profiles of PhotoCol^®—commercially available methacrylated type I collagen—photo-crosslinked with the photoinitiators: Lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), Irgacure 2959 (IRG), and Ruthenium/Sodium Persulfate (Ru/SPS) prior to evaluating PhotoCol^® permeability and LEC response to PhotoCol^® at stiffnesses representing normal and fibrotic tissues. Ru/SPS produced the highest stiffness (~6 kilopascal (kPa)) for photo-crosslinked PhotoCol^®, but stiffness did not change with burst light exposures (30 and 90 s). The collagen fibril area fraction increased, and dextran permeability (40 kilodalton (kDa)) decreased with photo-crosslinking, showing the impact of photo-crosslinking on microstructure and molecular transport. Human dermal LECs on softer, uncrosslinked PhotoCol^® (~0.5 kPa) appeared smaller with less prominent vascular endothelial (VE)-cadherin (cell–cell junction) expression compared to LECs on stiffer PhotoCol^® (~6 kPa), which had increased cell size, border irregularity, and VE-cadherin thickness (junction zippering) that is consistent with LEC morphology in fibrotic tissues. Our quantitative morphological analysis demonstrates our ability to produce LECs with a fibrotic phenotype, and the overall study shows that PhotoCol^® with Ru/SPS provides the necessary physical properties to systematically study LEC responses related to capillary growth and function under fibrotic conditions. Full article