The lymphatic system and sentinel lymph nodes: conduit for cancer metastasis

Heterogeneous Distribution and Absorbed Dose of Radiolabeled Nanoparticles and Colloids in Sentinel Lymph Nodes

Background: For breast cancer staging, radiolabeled colloids and superparamagnetic iron oxide nanoparticles (SPIONs) are used for sentinel lymph node (SLN) imaging. This study characterized the intranodal activity distribution and absorbed dose distribution. Material and Methods: Six patients diagnosed with primary breast cancer were intradermally injected with 99mTc-Nanocoll. The SLNs were resected, weighed, and measured for activity. Three groups of six rats were subcutaneously injected into the hind paw with either 99mTc-Nanocoll, 99mTc-SPIONs, or 68Ga-SPIONs. Macro- and small-scale dosimetry calculations were performed using autoradiography images of cryosections of SLNs from patients and animals. Results: The mean absorbed dose in patient SLNs was 0.5 ± 0.3 mGy/MBq for 99mTc-Nanocoll and 3.4 ± 1.8 mGy/MBq, assuming a 99mTc-Nanocoll-based distribution of 68Ga-SPIONs. Due to different decay characteristics, the heterogeneity in the absorbed dose differed between 99mTc-SPIONs and 68Ga-SPIONs with a maximum to mean absorbed dose ratio of 2.7 ± 0.3 and 1.6 ± 0.2, respectively. Conclusions: This study shows that 99mTc- and 68Ga-SPIONs and 99mTc-nanocolloids have similar activity distribution in human and animal lymph nodes. Small-scale dosimetry models combined with clinical patient biokinetics may serve as a bridge between organ and tissue dosimetry and the interpretation of intrinsic geometric variation and its uncertainties in absorbed dose.

Identification of Predictive Factors for the Development of In-Transit Metastasis in Patients with Melanoma

BACKGROUND

In patients with melanoma, in-transit metastasis (ITM) can develop. This study aimed to identify the risk for a first recurrence of ITM and associated predictive clinical factors in a large international cohort of patients with melanoma.

METHODS

Patients with primary cutaneous melanoma who underwent wide local excision (WLE) and sentinel lymph node biopsy (SLNB) were identified from the Sentinel Lymph Node Working Group (SLNWG) database between January 1993 and February 2023. Predictive factors for first recurrence of ITM were analyzed.

RESULTS

The study enrolled 7860 patients, and the median follow-up time was 47.1 months (interquartile range [IQR], 19.0-95.0 months). The risk for the development of ITM as a first recurrence was 4.12% (95% confidence interval [CI], 3.63-4.66%) at 5 years. The median time to first ITM recurrence was 15 months (IQR, 7.0-30.0 months). Significant clinicopathologic factors independently associated with an increased risk of ITM in multivariable analysis were increasing Breslow thickness (hazard ratio [HR], 1.37; 95% CI, 1.30-1.43; p < 0.0001), lower-extremity versus trunk melanoma (HR, 2.49; 95% CI, 1.86-3.32; p < 0.0001), increasing age (HR, 1.03; 95% CI, 1.02-1.04; p < 0.0001), number of positive sentinel lymph nodes (SLNs: 1 vs. 0 [HR, 2.24; 95% CI, 1.66-3.01; p < 0.0001] and 2 vs. 0 [HR, 2.37; 95% CI, 1.45-3.88; p = 0.0006]), and presence of vascular invasion (HR, 1.79; 95% CI, 1.21-2.64; p = 0.0035).

CONCLUSION

The independent risk factors for the development of ITM identified in a large international cohort of melanoma patients were Breslow thickness, lower-extremity melanoma, older age, number of positive SLNs, and presence of vascular invasion.

Function-preserving gastrectomy based on the sentinel node concept prevents osteosarcopenia in patients with gastric cancer

BACKGROUND

Gastric cancer remains a significant global challenge, with conventional surgery for early gastric cancer often leading to post-gastrectomy complications. Sentinel node navigation surgery is being developed to preserve quality of life without compromising radicality. Although osteosarcopenia is linked to gastrointestinal cancers and prognosis, its impact on bone and muscle mass after function-preserving surgery for gastric cancer remains underexplored.

METHODS

We analyzed the data of patients diagnosed with early gastric cancer and not eligible for endoscopic treatments, who underwent either distal gastrectomy or sentinel node navigation surgery at our hospital between 2010 and 2020. Skeletal muscle index and bone mineral density were measured preoperatively and 1, 3, and 5 years, postoperatively; rates of changes in these measures were assessed.

RESULTS

Among the 63 patients included, 42 (67%) underwent conventional surgery, and 21 (33%) underwent function-preserving gastrectomy using the sentinel node technique. No significant difference in postoperative survival rates was observed between the two groups (P = 0.97). The rate of change in the skeletal muscle index and bone mineral density decreased in both groups from 1 to 3 years postoperatively. At 5 years postoperatively, the sentinel node navigation surgery group showed an increase in skeletal muscle index and bone mineral density change rates, the difference observed between the two groups was significant (P < 0.05).

CONCLUSION

Sentinel node navigation surgery for early gastric cancer may help prevent decreases in bone and muscle mass. This suggests that its use has a potential role in preventing osteosarcopenia.

Axillary surgery versus no-axillary staging in T1N0 breast cancer: 20-year follow-up of the INT 09/98 randomized clinical trial

BACKGROUND

The role of axillary surgery in breast cancer has shifted over time from a therapeutic operation to a staging method for subsequent adjuvant therapies, through the introduction of sentinel lymph node biopsy. The discovery of molecular subtypes has since questioned the necessity of axillary staging in breast cancer.

METHODS

The INT09/98 randomized trial explored the omission of axillary surgery in early-stage breast cancer in patients under 65 years of age. From June 1998 to June 2003, a total of 565 T1N0 breast cancer patients were enrolled. The trial tested the non-inferiority of quadrantectomy without axillary surgery (QU) compared to quadrantectomy with axillary dissection (QUAD). The primary endpoint was overall survival (OS). Secondary endpoints included disease-free survival (DFS) and incidence/timing of axillary lymph node metastasis in the QU arm.

RESULTS

Follow-up at 20 years showed no significant differences between the QU versus the QUAD arm. The adjusted hazard ratio for OS was 1.18 (P = 0.326) and DFS was 1.27 (P = 0.280) respectively, both within the predetermined non-inferiority limit. Axillary relapse rates in the QU arm remained low, indicating that only a subset of metastatic nodes cause recurrences if not removed. In the QU arm, patients with favourable biological features but unknown axillary node involvement did not receive adjuvant chemotherapy, without significant differences in outcomes. The axillary relapse rate with distant metastases was similar in both arms and may reflect aggressive biology of the primary tumour.

CONCLUSION

Avoiding axillary surgery and reducing adjuvant treatments in early breast cancer does not increase distant metastases or affect long-term survival. Axillary relapsed patients with distant metastases in both QU and QUAD arms may represent cancers with genomically determined poorer prognosis, independent of surgical intervention and adjuvant therapies.

REGISTRATION NUMBER

NCT01508546 (http://www.clinicaltrials.gov).

Tannic acid-modified FK506-loaded nanoparticles targeting lymph nodes for acute heart transplant rejection treatment

Significant efforts have been made to deliver immunosuppressants-loaded nanoparticles (NPs) to lymph nodes (LNs) to mitigate transplant rejection. However, conventional administration techniques encounter challenges in enhancing the retention of NPs in the LNs. Attributing the strong affinity of tannic acid (TA) molecules to the elastin of LN conduits, we developed a novel formulation of NPs encapsulating Tacrolimus (FK506), and subsequently modified with TA to produce TA-FNP with a final diameter of approximately 86.07 ± 2.78 nm. These particles could traverse the the intercellular gaps in the lymphatic endothelial cells layers, enter the paracortex through LN capsule-associated conduits, and releases FK506 to inhibit the activation and proliferation of allogeneic T cells. Our finding demonstrated that TA-FNP could accumulate in LNs, significantly increasing the local concentration of FK506 from 69.06 ± 21.96 ng/g to 1041.28 ± 343.59 ng/g compared to the free FK506 treatment group. Subsequently, the therapeutic efficacy of TA-FNP was assessed in heart transplantation model, where treatment with TA-FNP resulted in decreased T cells infiltration within the grafts, reduced rejection grades, and a significant extension of graft survival time. In contrast, FNP without TA showed relatively poor therapeutic outcomes. Consequently, this study reveals a promising strategy utilizing TA to enhance the prolonged retention of FK506 within LNs, underscoring its potential therapeutic application in preventing heart transplant rejection.

Advances in molecular imaging and targeted therapeutics for lymph node metastasis in cancer: a comprehensive review

Lymph node metastasis is a critical indicator of cancer progression, profoundly affecting diagnosis, staging, and treatment decisions. This review article delves into the recent advancements in molecular imaging techniques for lymph nodes, which are pivotal for the early detection and staging of cancer. It provides detailed insights into how these techniques are used to visualize and quantify metastatic cancer cells, resident immune cells, and other molecular markers within lymph nodes. Furthermore, the review highlights the development of innovative, lymph node-targeted therapeutic strategies, which represent a significant shift towards more precise and effective cancer treatments. By examining cutting-edge research and emerging technologies, this review offers a comprehensive overview of the current and potential impact of lymph node-centric approaches on cancer diagnosis, staging, and therapy. Through its exploration of these topics, the review aims to illuminate the increasingly sophisticated landscape of cancer management strategies focused on lymph node assessment and intervention.

Tracing Sentinel Lymph Nodes and Inhibiting Lymphatic Metastasis with TiN Nanobipyramids Through Photothermal Therapy

Background

The lymphatic system is the major route of cancer metastasis, and sentinel lymph nodes (SLNs) are the first station for the spread of cancer cells. Accurate identification of SLNs by tracers during surgery is crucial for SLN biopsy and lymphadenectomy. However, conventional monomodal tracers such as blue dyes and carbon nanoparticles often induce a misjudgment of SLNs and thus are still unsatisfying for clinical applications. In addition, SLN imaging agents with therapeutic capabilities to achieve perfect theranostics have been less exploited.

Purpose

Titanium nitride (TiN) nanostructures have the advantages of high stability and low cost and show superior plasmonic properties over both the visible and near-infrared (NIR) regions. Herein we report on the synthesis of TiN nanobipyramids (NBPs) with large sizes for multimodal SLN mapping.

Methods

A hydrothermal method and post nitridation treatment were used to prepare the TiN NBPs. Bright- and dark-field imaging of SLNs with TiN NBPs were performed. The effect of TiN NBP size on SLN tracing was studied. The effect of TiN NBP-based photothermal ablation of SLNs combined with removal of primary tumors on pulmonary metastasis was studied.

Results

The TiN NBPs with dual bright- and dark-field imaging functions show high drainage in lymph nodes and thus can act as a potential substitute for SLN tracing. Moreover, owing to the superior plasmonic properties of TiN nanostructures, the produced TiN NBPs show a high photothermal conversion efficiency under 1064 nm laser irradiation. TiN NBP-based photothermal ablation of metastatic LNs in the second NIR window (NIR-II) combined with surgical removal of primary tumors shows remarkable inhibition of pulmonary metastasis.

Conclusion

This study not only demonstrates TiN NBPs as a new tracer for SLN mapping, but also presents a strategy for the photothermal ablation of lymph nodes in NIR-II for the inhibition of lymphatic metastasis.

Lymphedema: Current Strategies for Diagnostics and Management

ABSTRACT

Lymphedema (LE) is characterized by the accumulation of lymph in the extremities, impairing functionality and quality of life. Despite its prevalence, accurate diagnoses and management remains complex because of inconsistencies in diagnostic criteria and limited epidemiological studies. This review aims to address this gap by providing a comprehensive overview of LE classifications, diagnostic approaches, and current management strategies. By synthesizing existing knowledge, this study seeks to contribute to a deeper understanding of LE for improvement of clinical consistency and education.

Lymph node metastasis in cancer: Clearing the clouds to see the dawn

Lymph node metastasis (LNM) is often regarded as an indicator of poor prognosis in various cancers. Despite over three centuries of exploration since its discovery, the molecular mechanisms underlying LNM remain inconclusive. This review summarizes the molecular mechanisms of LNM, using the "PUMP+" principle for clarification. Pathological examination remains the gold standard for LNM diagnosis, yet there is a need to explore early diagnostic strategies that can effectively improve patient outcomes. With the advent of immunotherapy, discussions on the fate of lymph nodes (LN) have emerged, emphasizing the importance of preserving LN integrity prior to immunotherapy. This, in turn, poses higher demands for diagnostic accuracy and precision treatment of LNM. This review comprehensively discusses the molecular mechanisms, diagnostic methods, and treatment strategies for cancer lymph node metastasis, along with current bottlenecks and future directions in this field.

Unravelling the biological and clinical challenges of circulating tumour cells in epithelial ovarian carcinoma

Epithelial ovarian carcinoma (EOC) is the eighth most common cancer in women and the leading cause of gynaecological cancer death, predominantly due to the absence of effective screening tools, advanced stage at diagnosis, and high rates of recurrence. Circulating tumour cells (CTCs), a rare subset of tumour cells that disseminate from a tumour and migrate into the circulation, play a pivotal role in the metastatic cascade, and therefore hold promise as biomarkers for disease monitoring and prognostication. Exploring CTCs from liquid biopsies is an appealing approach for research and clinical practice, given it is minimally invasive, facilitates serial sampling and enables the capture of the entire spectrum of cancer cells circulating in the blood. The prognostic utility of CTC enumeration has been FDA-approved for clinical use in metastatic breast, prostate, and colorectal cancers. However, the unique biology of EOC, discussed herein, compounds the detection and characterisation complexities already inherent in CTC research, consequently hindering progress towards clinical applications. The aim of this review is to provide an overview of both the biological and clinical challenges encountered in harnessing the power of CTCs in EOC.

Intramammary Tumor Location and Ipsilateral Lymphatic Spread in Early Breast Cancer Patients Using One-Step Nucleic Acid Amplification (OSNA) Assay

Establishing an accurate prognosis for women diagnosed with breast cancer (BC) is extremely challenging. Axillary lymph node (ALN) evaluation is considered of major prognostic value. The one-step nucleic acid amplification (OSNA) assay is currently used for assessing axillary sentinel lymph node (SLN) status in BC. Additionally, total tumor load (TTL) may help predict further metastatic axillary involvement beyond the SLN. The prognostic value of primary BC location remains controversial due to lack of consensus on the biological differences among tumors at various sites. Evidence suggests that tumors in the internal quadrants (INLs) have worse prognosis compared to those in the external quadrants. Furthermore, ALN involvement is believed to be mainly associated with external quadrant tumors, mainly due to the lymphatic drainage system of the breast. This pilot observational study, despite lacking a control group and having a relatively small sample size, is the first to evaluate the potential relationship between primary BC location and ALN metastasis using the OSNA assay. A sample of consecutive BC patients undergoing axillary staging with the OSNA assay were included. Tumors were categorized into three groups based on primary location: external quadrants and axillary tail (EXL), INLs, and nipple and areola location (NAL). Although not statistically significant, the INL group exhibited a higher mean TTL. Additionally, no significant differences were observed between groups concerning SLN detection techniques, SLN status, number of metastatic SLN, or mean TTL. These findings support the use of the innovative tracer superparamagnetic iron oxide regardless of tumor site. This study underscores the importance of understanding the relationship between BC location and ALN status, which may improve prognostic stratification and targeted therapies based on tumor site. If these observations are confirmed in larger, multicentric studies, the potential conclusions may shift the paradigm of INL tumor treatment, significantly impacting clinical practice and research.

Programmable Release of Chemotherapeutics from Ferrocene-Based Injectable Hydrogels Slows Melanoma Growth

Hydrogel-based injectable drug delivery systems provide temporally and spatially controlled drug release with reduced adverse effects on healthy tissues. Therefore, they represent a promising therapeutic option for unresectable solid tumor entities. In this study, a peptide-starPEG/hyaluronic acid-based physical hydrogel is modified with ferrocene to provide a programmable drug release orchestrated by matrix-drug interaction and local reactive oxygen species (ROS). The injectable ROS-responsive hydrogel (hiROSponse) exhibits adequate biocompatibility and biodegradability, which are important for clinical applications. HiROSponse is loaded with the two cytostatic drugs (hiROSponsedox/ptx) doxorubicin (dox) and paclitaxel (ptx). Dox is a hydrophilic compound and its release is mainly controlled by Fickian diffusion, while the hydrophobic interactions between ptx and ferrocene can control its release and thus be regulated by the oxidation of ferrocene to the more hydrophilic state of ferrocenium. In a syngeneic malignant melanoma-bearing mouse model, hiROSponsedox/ptx slows tumor growth without causing adverse side effects and doubles the relative survival probability. Programmable release is further demonstrated in a tumor model with a low physiological ROS level, where dox release, low dose local irradiation, and the resulting ROS-triggered ptx release lead to tumor growth inhibition and increased survival.

Cancer metastasis through the lymphatic versus blood vessels

Whether cancer cells metastasize from the primary site to the distant sites via the lymphatic vessels or the blood vessels directly into the circulation is still under intense study. In this review article, we follow the journey of cancer cells metastasizing to the sentinel lymph nodes and beyond to the distant sites. We emphasize cancer heterogeneity and microenvironment as major determinants of cancer metastasis. Multiple molecules have been found to be associated with the complicated process of metastasis. Based on the large sentinel lymph node data, it is reasonable to conclude that cancer cells may metastasize through the blood vessels in some cases but in most cases, they use the sentinel lymph nodes as the major gateway to enter the circulation to distant sites.

Interrogating the roles of lymph node metastasis in systemic immune surveillance

Lymph nodes (LNs) are principal orchestrators of the adaptive immune response, yet in the context of malignancy, they are typically the first sites of metastasis. When tumors spread to LNs, they alter the immune repertoire, ultimately reconditioning it in a manner that suppresses anti-tumor immunity and promotes further metastatic dissemination. Conversely, activation of anti-tumor immunity within LNs is essential for immunotherapy, suggesting clinical approaches to radiotherapy in LNs and lymphadenectomy may need to be reconsidered in the context of immune checkpoint blockade (ICB). Herein, we discuss our understanding of the immune remodeling that coincides with LN metastasis as well as recent clinical studies exploring neoadjuvant immunotherapy and the roles of LNs in treatment of solid organ malignancies.

Dynamics of Endothelial Cell Diversity and Plasticity in Health and Disease

Endothelial cells (ECs) are vital structural units of the cardiovascular system possessing two principal distinctive properties: heterogeneity and plasticity. Endothelial heterogeneity is defined by differences in tissue-specific endothelial phenotypes and their high predisposition to modification along the length of the vascular bed. This aspect of heterogeneity is closely associated with plasticity, the ability of ECs to adapt to environmental cues through the mobilization of genetic, molecular, and structural alterations. The specific endothelial cytoarchitectonics facilitate a quick structural cell reorganization and, furthermore, easy adaptation to the extrinsic and intrinsic environmental stimuli, known as the epigenetic landscape. ECs, as universally distributed and ubiquitous cells of the human body, play a role that extends far beyond their structural function in the cardiovascular system. They play a crucial role in terms of barrier function, cell-to-cell communication, and a myriad of physiological and pathologic processes. These include development, ontogenesis, disease initiation, and progression, as well as growth, regeneration, and repair. Despite substantial progress in the understanding of endothelial cell biology, the role of ECs in healthy conditions and pathologies remains a fascinating area of exploration. This review aims to summarize knowledge and concepts in endothelial biology. It focuses on the development and functional characteristics of endothelial cells in health and pathological conditions, with a particular emphasis on endothelial phenotypic and functional heterogeneity.

Nanomaterial-Based Strategies for Preventing Tumor Metastasis by Interrupting the Metastatic Biological Processes

Tumor metastasis is the primary cause of cancer-related deaths. The prevention of tumor metastasis has garnered notable interest and interrupting metastatic biological processes is considered a potential strategy for preventing tumor metastasis. The tumor microenvironment (TME), circulating tumor cells (CTCs), and premetastatic niche (PMN) play crucial roles in metastatic biological processes. These processes can be interrupted using nanomaterials due to their excellent physicochemical properties. However, most studies have focused on only one aspect of tumor metastasis. Here, the hypothesis that nanomaterials can be used to target metastatic biological processes and explore strategies to prevent tumor metastasis is highlighted. First, the metastatic biological processes and strategies involving nanomaterials acting on the TME, CTCs, and PMN to prevent tumor metastasis are briefly summarized. Further, the current challenges and prospects of nanomaterials in preventing tumor metastasis by interrupting metastatic biological processes are discussed. Nanomaterial-and multifunctional nanomaterial-based strategies for preventing tumor metastasis are advantageous for the long-term fight against tumor metastasis and their continued exploration will facilitate rapid progress in the prevention, diagnosis, and treatment of tumor metastasis. Novel perspectives are outlined for developing more effective strategies to prevent tumor metastasis, thereby improving the outcomes of patients with cancer.

Diagnostic value of one-step nucleic acid amplification for sentinel lymph node metastasis in cytokeratin 19-positive tumors: evidence from bioinformatics and meta-analysis

Background

The status of the sentinel lymph nodes (SLNs) was an important prognostic factor in varies cancers. A one-step nucleic acid amplification (OSNA) assay, a molecular-based whole-node analysis method based on CK19 mRNA copy number, was developed to diagnose lymph node metastases. We aimed to evaluate the value of OSNA for the diagnosis of sentinel lymph node metastasis in CK19 positive cancers. CK19 mRNA and protein expression for pan-caner analysis were obtained from TCGA and the Human protein atlas database.

Methods

Two researchers independently searched the PubMed, Cochrane Library and Web of Science databases for qualified articles published before December 1, 2023. A meta-analysis was performed using MetaDisc and STATA. Risk bias and quality assessments of the included studies were evaluated, and a subgroup analysis was performed. Ten cancer types were found to be CK19 positively expressed and 7 of 10 had been reported to use OSNA for SLN detection.

Results

After literature review, there were 61 articles included in the meta-analysis, which consisted of 7115 patients with 18007 sentinel lymph nodes. The pooled sensitivity and specificity of OSNA were 0.87 and 0.95 in overall patients. Moreover, we found the background CK19 expression in normal tissue affected the diagnostic accuracy of OSNA. In breast cancer, we performed subgroup analysis. OSNA exhibited to be a stable method across different population groups and various medical centers. In addition, when 250 copies/μl was chosen as the cutoff point of CK19 mRNA, there were a relatively higher sensitivity and AUC in detecting SLN micro-metastasis than 5000 copies/μl.

Discussion

OSNA can predict the occurrence of SLN metastasis accurately in CK19 positive cancers, especially in breast cancer, colorectal cancer, lung cancer, gastric cancer and endometrial cancer. Our study warrants future studies investigating the clinical application of OSNA in pancreatic, ovarian and bladder cancers.

The role of micrometastasis in high-risk skin cancers

The propensity to metastasize is the most important prognostic indicator for solid cancers. New insights into the mechanisms of early carcinogenesis have revealed micrometastases are generated far earlier than previously thought. Evidence supports a synergistic relationship between vascular and lymphatic seeding which can occur before there is clinical evidence of a primary tumour. Early vascular seeding prepares distal sites for colonisation while regional lymphatics are co-opted to promote facilitative cancer cell mutations. In response, the host mounts a global inflammatory and immunomodulatory response towards these cells supporting the concept that cancer is a systemic disease. Cancer staging systems should be refined to better reflect cancer cell loads in various tissue compartments while clinical perspectives should be broadened to encompass this view when approaching high-risk cancers. Measured adjunctive therapies implemented earlier for low-volume, in-transit cancer offers the prospect of preventing advanced disease and the need for heroic therapeutic interventions. This review seeks to re-appraise how we view the metastatic process for solid cancers. It will explore in-transit metastasis in the context of high-risk skin cancer and how it dictates disease progression. It will also discuss how these implications will influence our current staging systems and its consequences on management.

Pharmacokinetic Study of Ultrasmall Superparamagnetic Iron Oxide Nanoparticles HY-088 in Rats

BACKGROUND AND OBJECTIVE

HY-088 injection is an ultrasmall superparamagnetic iron oxide nanoparticle (USPIOs) composed of iron oxide crystals coated with polyacrylic acid (PAA) on the surface. The purpose of this study was to investigate the pharmacokinetics, tissue distribution, and mass balance of HY-088 injection.

METHODS

The pharmacokinetics of [55Fe]-HY-088 and [14C]-HY-088 were investigated in 48 SD rats by intravenous injection of 8.5 (low-dose group), 25.5 (medium-dose group), and 85 (high-dose group) mg/100 μCi/kg. Tissue distribution was studied by intravenous injection of 35 mg/100 μCi/kg in 48 SD rats, and its tissue distribution in vivo was obtained by ex vivo tissue assay. At the same time, [14C]-HY-088 was injected intravenously at a dose of 25.5 mg/100 μCi/kg into 16 SD rats, and its tissue distribution in vivo was studied by quantitative whole-body autoradiography. [14C]-HY-088 and [55Fe]-HY-088 were injected intravenously into 24 SD rats at a dose of 35 mg/100 μCi/kg, and their metabolism was observed.

RESULTS

In the pharmacokinetic study, [55Fe]-HY-088 reached the maximum observed concentration (Cmax) at 0.08 h in the low- and medium-dose groups of SD rats. [14C]-HY-088 reached Cmax at 0.08 h in the three groups of SD rats. The area under the concentration-time curve (AUC) of [55Fe]-HY-088 and [14C]-HY-088 increased with increasing dose. In the tissue distribution study, [55Fe]-HY-088 and [14C]-HY-088 were primarily distributed in the liver, spleen, and lymph nodes of both female and male rats. In the mass balance study conducted over 57 days, the radioactive content of 55Fe from [55Fe]-HY-088 was primarily found in the carcass, accounting for 86.42 ± 4.18% in females and 95.46 ± 6.42% in males. The radioactive recovery rates of [14C]-HY-088 in the urine of female and male rats were 52.99 ± 5.48% and 60.66 ± 2.23%, respectively.

CONCLUSIONS

Following single intravenous administration of [55Fe]-HY-088 and [14C]-HY-088 in SD rats, rapid absorption was observed. Both [55Fe]-HY-088 and [14C]-HY-088 were primarily distributed in the liver, spleen, and lymph nodes. During metabolism, the radioactivity of [55Fe]-HY-088 is mainly present in the carcass, whereas the 14C-labeled [14C]-HY-088 shell PAA is eliminated from the body mainly through the urine.

Evaluation of the diagnostic value of Sentinel Lymph Node in patients with gastric adenocarcinoma

Objectives

Sentinel lymph node biopsy (SLNB) has been proven as a safe and efficient procedure in some cancers like breast cancer and melanoma with a reduction of complications and side effects of unnecessary lymphadenectomy in many patients. However, the diagnostic value of SLNB in gastric cancer is a point of debate. This study evaluated the diagnostic value of SLNB using radiotracer and isosulphan blue dye injection in patients with Gastric Adenocarcinomas (GA).

Methods

This descriptive study was performed at Imam-Reza HOSPITAL on 39 patients diagnosed with GA with no lymphatic metastasis using two methods: the combination of radionuclide with isosulphan together (R&I) method compared with the isosulphan alone method. Lymphatic dissection was performed in all patients. The pathological results were compared between the sentinel lymph nodes (SLN) and other lymph nodes and their accordance rate was calculated.

Results

In the T1 group, the sentinel lymph node biopsy detection rate was 100% for the combination of the R&I method and 60% for the isosulphan method and the false negative rate was zero. These values respectively were 88.8% and 88.8% in the T2 group with a false negative rate of 75%. In the T3 group, the values were 100% for the combination of the R&I method and 93.7% for the isosulphan method with a false negative rate of 40%. In the combination of the R&I method, the sensitivity, specificity, and positive and negative predictive values were 57.9, 100, 100, and 69.2 percent respectively.

Conclusion

Based on the false negative rate (47.4%), SLNB by injection of isosulphan blue dye alone is not a diagnostic enough value for predicting lymph node metastasis in GA. Although, SLNB by combination of the R&I had better accuracy compared to the isosulphan alone, more studies with larger samples are needed to prove this result.

Sentinel lymph node assessment in melanoma: current state and future directions

Assessment of sentinel lymph node status is an important step in the evaluation of patients with melanoma for both prognosis and therapeutic management. Pathologists have an important role in this evaluation. The methodologies have varied over time, from the evaluation of dimensions of metastatic burden to determination of the location of the tumour deposits within the lymph node to precise cell counting. However, no single method of sentinel lymph node tumour burden measurement can currently be used as a sole independent predictor of prognosis. The management approach to sentinel lymph node-positive patients has also evolved over time, with a more conservative approach recently recognised for selected cases. This review gives an overview of past and current status in the field with a glimpse into future directions based on prior experiences and clinical trials.

Protein@Cyanine-Based NIR-II Lymphography Enables the Supersensitive Visualization of Lymphedema and Tumor Lymphatic Metastasis

Visualization of the lymphatic system is clinically indispensable for the diagnosis and/or treatment of lymphatic diseases. Although indocyanine green (ICG) lymphography becomes an alternate imaging modality compared to traditional lymphoscintigraphy, it is still far from ideal due to the insufficient detection depth and low spatiotemporal resolution. Herein, protein@cyanine probes are rationally developed to solve the limitations of the current near-infrared-I (NIR-I) lymphography. The protein@cyanine probes are synthesized following a chlorine-containing dye-labeling strategy based on structure-selectivity (facile covalent binding between the dye and protein with a 1:1 molar ratio). As expected, the probes display exceptional NIR-II imaging ability with much-improved imaging contrast/resolution and controllable pharmacokinetics, superior to the clinical ICG. The protein@cyanine probes locate lymph nodes and delineate lymphatic vessels with super-high sensitivity and signal-to-background ratio, enabling real-time diagnosing lymphatic diseases such as lymphedema and tumor lymphatic metastasis. In particular, the NIR-II lymphography provides an opportunity to discover the disparate morbidity rate of primary lymphedema in different types of mice. Given the fact of lacking clinically transferable NIR-II probes, this work not only provides a promising strategy for enriching of the current library of NIR-II probes, but also promotes the clinical translation of NIR-II lymphography technology.

Lymph node metastasis in cancer progression: molecular mechanisms, clinical significance and therapeutic interventions

Lymph nodes (LNs) are important hubs for metastatic cell arrest and growth, immune modulation, and secondary dissemination to distant sites through a series of mechanisms, and it has been proved that lymph node metastasis (LNM) is an essential prognostic indicator in many different types of cancer. Therefore, it is important for oncologists to understand the mechanisms of tumor cells to metastasize to LNs, as well as how LNM affects the prognosis and therapy of patients with cancer in order to provide patients with accurate disease assessment and effective treatment strategies. In recent years, with the updates in both basic and clinical studies on LNM and the application of advanced medical technologies, much progress has been made in the understanding of the mechanisms of LNM and the strategies for diagnosis and treatment of LNM. In this review, current knowledge of the anatomical and physiological characteristics of LNs, as well as the molecular mechanisms of LNM, are described. The clinical significance of LNM in different anatomical sites is summarized, including the roles of LNM playing in staging, prognostic prediction, and treatment selection for patients with various types of cancers. And the novel exploration and academic disputes of strategies for recognition, diagnosis, and therapeutic interventions of metastatic LNs are also discussed.

Effective treatment of metastatic sentinel lymph nodes by dual-targeting melittin nanoparticles

Sentinel lymph node (SLN) metastasis is an important promoter of distant metastasis in breast cancer. Therefore, the timely diagnosis and precise treatment are crucial for patient staging and prognosis. However, the simultaneous diagnosis of metastasis and the implementation of imaging-guided SLN therapy is challenging. Here, we report a melittin-loaded and hyaluronic acid (HA)-conjugated high-density lipoprotein (HDL) mimic phospholipid scaffold nanoparticle (MLT-HA-HPPS), which dually-target to both breast cancer and its SLN and efficiently inhibit SLN metastasis in the LN metastasis model. The melittin peptide was successfully loaded onto HA-HPPS via electrostatic interactions, and MLT-HA-HPPS possesses effective cytotoxicity for breast cancer 4T1 cells. Moreover, the effective delivery of MLT-HA-HPPS from the primary tumor into SLN is monitored by NIR fluorescence imaging, which greatly benefits the prognosis and treatment of metastatic SLNs. After paracancerous administration, MLT-HA-HPPS can efficiently inhibit primary tumor growth with an inhibition rate of 81.3% and 76.5% relative to the PBS-treated control group and HA-HPPS group, respectively. More importantly, MLT-HA-HPPS can effectively inhibit the growth of the metastatic SLNs with an approximately 78.0%, 79.1%, and 64.2% decrease in SLNs weight than those in PBS, HA-HPPS, and melittin-treated mice, respectively. Taken together, the MLT-HA-HPPS may provide an encouraging theranostic of SLN drug delivery strategy to inhibit primary tumor progression and prevent SLN metastasis of breast cancer.

The Lucerne Toolbox 2 to optimise axillary management for early breast cancer: a multidisciplinary expert consensus

Clinical axillary lymph node management in early breast cancer has evolved from being merely an aspect of surgical management and now includes the entire multidisciplinary team. The second edition of the "Lucerne Toolbox", a multidisciplinary consortium of European cancer societies and patient representatives, addresses the challenges of clinical axillary lymph node management, from diagnosis to local therapy of the axilla. Five working packages were developed, following the patients' journey and addressing specific clinical scenarios. Panellists voted on 72 statements, reaching consensus (agreement of 75% or more) in 52.8%, majority (51%-74% agreement) in 43.1%, and no decision in 4.2%. Based on the votes, targeted imaging and standardized pathology of lymph nodes should be a prerequisite to planning local and systemic therapy, axillary lymph node dissection can be replaced by sentinel lymph node biopsy ( ± targeted approaches) in a majority of scenarios; and positive patient outcomes should be driven by both low recurrence risks and low rates of lymphoedema.

The Sentinel Lymph Node in Treatment Planning: A Narrative Review of Lymph-Flow-Guided Radiotherapy

The sentinel lymph node technique is minimally invasive and used routinely by surgeons, reducing the need for morbid extensive lymph node dissections, which is a significant advantage for cancer staging and treatment decisions. The sentinel lymph node could also help radiation oncologists to identify tumor drainage for each of their patients, leading to a more personalized radiotherapy, instead of a probabilistic irradiation based on delineation atlases. The aim is both to avoid recurrence in unexpected areas and to limit the volume of irradiated healthy tissues. The aim of our study is to evaluate the impact of sentinel lymph node mapping for radiation oncologists. This concept, relying on sentinel lymph node mapping for treatment planning, is known as lymph-flow-guided radiotherapy. We present an up-to-date narrative literature review showing the potential applications of the sentinel lymph node technique for radiotherapy, as well as the limits that need to be addressed before its routine usage.

Albumin-based nanoparticle for dual-modality imaging of the lymphatic system

The lymphatic system is a complex network of lymphatic vessels, lymph nodes, and lymphoid organs. The current understanding of the basic mechanism and framework of the lymphatic system is relatively limited and not ideal for exploring the function of the lymphatic system, diagnosing lymphatic system diseases, and controlling tumor metastasis. Imaging modalities for evaluating lymphatic system diseases mainly include lymphatic angiography, reactive dye lymphatic angiography, radionuclide lymphatic angiography, computed tomography, and ultrasonography. However, these are insufficient for clinical diagnosis. Some novel imaging methods, such as magnetic resonance imaging, positron emission computed tomography, single-photon emission computed tomography, contrast-enhanced ultrasonography, and near-infrared imaging with agents such as cyanine dyes, can reveal lymphatic system information more accurately and in detail. We fabricated an albumin-based fluorescent probe for dual-modality imaging of the lymphatic system. A near-infrared cyanine dye, IR-780, was absorbed into bovine serum albumin (BSA), which was covalently linked to a molecule of diethylenetriaminepentaacetic acid to chelate gadolinium Gd3+. The fabricated IR-780@BSA@Gd3+ nanocomposite demonstrates strong fluorescence and high near-infrared absorption and can be used as a T1 contrast agent for magnetic resonance imaging. In vivo dual-modality fluorescence and magnetic resonance imaging showed that IR-780@BSA@Gd3+ rapidly returned to the heart through the lymphatic circulation after it was injected into the toe webs of mice, facilitating good lymphatic imaging. The successful fabrication of the new IR-780@BSA@Gd3+ nanocomposite will facilitate the study of the mechanism and morphological structure of the lymphatic system.

Lymph node lymphatic endothelial cells as multifaceted gatekeepers in the immune system

Single-cell technologies have recently allowed the identification of multiple lymphatic endothelial cell (LEC) subsets in subcapsular, paracortical, medullary, and other lymph node (LN) sinus systems in mice and humans. New analyses show that LECs serve key immunological functions in the LN stroma during immune responses. We discuss the roles of different LEC types in guiding leukocyte and cancer cell trafficking to and from the LN parenchyma, in capturing microbes, and in transporting, presenting, and storing lymph-borne antigens in distinct types of lymphatic sinuses. We underscore specific adaptations of human LECs and raise unanswered questions concerning LEC functions in human disease. Despite our limited understanding of human lymphatics - hampering clinical translation in inflammation and metastasis - we support the potential of LN LECs as putative targets for boosting/inhibiting immunoreactivity.

Nanoadjuvants Actively targeting lymph node conduits and blocking tumor invasion in lymphatic vessels

Great efforts have been made to manipulate nanoparticles (NPs) with a diameter of 10-100 nm to passively target lymph nodes (LNs) to magnitude anti-tumor activity of T cells. However, no attention has been paid to increasing the retention of NPs with active affinity in order to induce a prolonged release of antigens or molecular adjuvants in the LNs mattering the immune response. Here, we formulated two NPs encapsulated with imiquimod (IMQ), a TLR7/8 agonist, and paclitaxel (PTX) and further modified them with tannic acid (TA), respectively, to generate IMQ NP and PTX NP with a final diameter of approximately 40 nm. Attributing a strong affinity of TA molecules to the elastin of LN conduits, the TA modified IMQ NPs can bypass the gaps in the layer of lymphatic endothelial cells and enter the paracortex through the lymph node capsule-associated (LNC) conduits. Similarly, the TA modified PTX NPs increased delivery of PTX to the metastatic tumor site in LNs, where the tumor-associated antigens were released and presented by conduits-lining dendritic cells to activate T cells. Thus, the NPs with deposition to LN conduits showed excellent performance in preventing lymphovascular invasion of triple-negative breast cancer cells and lung metastasis thereafter. On the contrary, the NPs without TA flowed through the subcutaneous sinus existing LNs directly by efferent lymphatic vessels showing relatively poor therapeutic outcomes. This study reveals that TA may mediate the long retention of antigens and molecular adjuvants to be delivered to deep LNs for developing potent vaccination technology.

The Microvascular-Lymphatic Interface and Tissue Homeostasis: Critical Questions That Challenge Current Understanding

Lymphatic and blood microvascular networks play critical roles in the clearance of excess fluid from local tissue spaces. Given the importance of these dynamics in inflammation, tumor metastasis, and lymphedema, understanding the coordinated function and remodeling between lymphatic and blood vessels in adult tissues is necessary. Knowledge gaps exist because the functions of these two systems are typically considered separately. The objective of this review was to highlight the coordinated functional relationships between blood and lymphatic vessels in adult microvascular networks. Structural, functional, temporal, and spatial relationships will be framed in the context of maintaining tissue homeostasis, vessel permeability, and system remodeling. The integration across systems will emphasize the influence of the local environment on cellular and molecular dynamics involved in fluid flow from blood capillaries to initial lymphatic vessels in microvascular networks.

Metabolic Reprogramming in Tumor Endothelial Cells

The dynamic crosstalk between the different components of the tumor microenvironment is critical to determine cancer progression, metastatic dissemination, tumor immunity, and therapeutic responses. Angiogenesis is critical for tumor growth, and abnormal blood vessels contribute to hypoxia and acidosis in the tumor microenvironment. In this hostile environment, cancer and stromal cells have the ability to alter their metabolism in order to support the high energetic demands and favor rapid tumor proliferation. Recent advances have shown that tumor endothelial cell metabolism is reprogrammed, and that targeting endothelial metabolic pathways impacts developmental and pathological vessel sprouting. Therefore, the use of metabolic antiangiogenic therapies to normalize the blood vasculature, in combination with immunotherapies, offers a clinical niche to treat cancer.

Survival analysis in head and neck melanoma after negative sentinel lymph node biopsy: A seer-based population study

BACKGROUND

Cutaneous malignant melanoma (CMM) is one of the most aggressive skin tumors. Sentinel lymph node biopsy (SLNB) is an important test before thorough treatment of melanoma. The aim of this study was to investigate cancer-specific survival (CSS) in patients with head and neck CMM after negative SLNB and to analyze predictors of decreased survival.

METHODS

Based on the Surveillance, Epidemiology and End Results (SEER) database, a study was conducted using data from patients with head and neck CMM after negative SLNB. The demographic, clinical, and pathological characteristics of the case population were analyzed. Cox univariate, Kaplan-Meier analysis, and multivariate Cox regression models were used to explore predictors of decreased survival; propensity score matching (PSM) analysis was used to reduce confounding bias, and outcomes were compared between the wide margin excision and narrow margin excision groups.

RESULTS

A total of 1597 confirmed head and neck CMM patients with SLNB-negative were found. A Breslow>4.0 mm was the highest independent risk predictor for patients (HR 3.82, 95% CI 2.04-7.16, P < .001), and significant risk independent predictors also included a high mitotic rate >4 (HR 1.54, 95% CI 1.06-2.25, P = .023). Age< 60 years old was a significant survival predictor (HR 0.56, 95% CI .37-.85, P = .007), and not scalp and neck CMM were also important factors for longer survival (auricle skin: HR .51, 95% CI .29-.90, P = .02; unspecified parts of face: HR .59, 95% CI .40-.87, P = .007). After harmonizing baseline data by PSM, it was found that the extent of surgical resection did not affect patient survival.

CONCLUSION

This study analyzed the risk factors affecting CSS in patients with CMM of the head and neck region with SLNB-negative and observed a statistically significant difference in the prognosis of patients with CMM in different aesthetic subunits of the head and neck region. Close clinical follow-up for this population is necessary, and periodic medical examinations should be carried out.

A novel targeted multifunctional nanoplatform for visual chemo-hyperthermia synergy therapy on metastatic lymph nodes via lymphatic delivery

Background

Distant metastasis to vital organs is the major contributor to breast cancer mortality, and regional lymph node metastasis is an important facilitator of distant metastasis and recurrence in this cancer. The early diagnosis and precise treatment of lymph node metastasis are crucial for staging and prognosis in breast cancer. Herein, we report a visualized precision medicine nanoplatform of metastatic lymph nodes for ultrasonic/photoacoustic (US/PA) dual modal imaging-guided in situ targeted hyperthermia-combined chemotherapy.

Results

Carbon nanoparticles (CNs), approved by the China Food and Drug Administration, were loaded with docetaxel and rationally combined with anti-hypoxia-inducible factor 1α antibody-modified poly (lactic-co-glycolic acid) (PLGA) nanoparticles to achieve the combination of passive targeting at the lymph nodes and intracellular targeting at HIF 1α factor. The accumulation and retention of nanoparticles in metastatic lymph nodes via lymphatic delivery were enhanced. Docetaxel could be effectively offloaded by CNs that have active carbon nanoparticles, and the PLGA membrane prevented drug leakage. The nanoparticles exhibited excellent photothermal performance with a photothermal conversion efficiency of 28.9%, killing tumor cells in metastatic lymph nodes through hyperthermia. In vitro and in vivo systematic evaluations revealed that hyperpyrexia triggered the rupture of nanoparticles caused by the phase transition of perfluorohexane, resulting in docetaxel release for achieving in situ hyperthermia-combined chemotherapy.

Conclusions

The laser-triggered highly efficient in situ chemotherapy nanosystem achieves targeted synergistic chemo-hyperthermia treatment of metastatic lymph nodes, and lymphatic delivery represents a strategy to avoid additional injury caused by drugs entering the blood circulation.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-01186-8.