Lymphatic Drainage Patterns Research Articles

Percutaneous contrast-enhanced ultrasound for localization and qualitative diagnosis of sentinel lymph nodes in cutaneous malignant melanoma of lower extremities: a preliminary study.

To explore the feasibility of sentinel lymph node (SLN) tracing by percutaneous contrast-enhanced ultrasound (pCEUS) in patients with cutaneous malignant melanoma (CMM) and the ability to enhance patterns of SLNs in diagnosing lymph nodes (LNs) metastases. Fifty-three patients with CMM of the lower extremities treated at our hospital were included in the study. All the participants received pCEUS preoperatively. The enhanced lymphatic channels (LCs) and associated SLNs were observed and tracked in real-time. The number of enhanced LCs and enhancing patterns of SLNs were recorded. Subsequently, SLNs localized by pCEUS were pathologically examined. Of the 53 cases, SLNs were successfully localized by pCEUS in 48 cases. In total, there were 59 detected SLNs averaging 1.23±0.42 SLNs per case. The main lymphatic drainage patterns (LDPs) were the following: one enhanced LC pointed to one or more than one SLN, and multiple enhanced LCs pointed to one or multiple SLNs. There were four enhancing patterns of SLNs (uniform, annular, uneven, and no enhancement), among which the first two were considered benign nodes, while the latter two were considered metastatic nodes. With pathological results as the gold standard, the diagnostic sensitivity and specificity by pCEUS were 90.9% and 75.0%, respectively. Contrast-enhanced ultrasound (US) is a feasible approach for SLN identification in patients with CMM of the lower extremities. Enhancing patterns of SLNs may help predict metastasizing SLNs. This novel method may be a promising technique for clinical application.

Methods of Sentinel Lymph Node Identification in Auricular Melanoma.

Background:Sentinel lymph node biopsy is used to evaluate for micrometastasis in auricular melanoma. However, lymphatic drainage patterns of the ear are not well defined and predicting the location of sentinel nodes can be difficult. The goal of this study was to define the lymphatic drainage patterns of the ear and to compare multiple modalities of sentinel node identification.Methods:A retrospective review of a prospectively maintained database evaluated 80 patients with auricular melanoma who underwent sentinel lymph node biopsy by comparing preoperative imaging with intraoperative identification of sentinel nodes. Patients were placed into two cohorts, based on the modality of preoperative imaging: (1) planar lymphoscintigraphy only (n = 63) and (2) single-photon emission computerized tomography combined with computerized tomography (SPECT-CT) only (n = 17). Sites of preoperative mapping and sites of intraoperative identification were recorded as parotid/preauricular, mastoid/postauricular, and/or cervical.Results:In patients that underwent planar lymphoscintigraphy preoperatively (n = 63), significantly more sentinel nodes were identified intraoperatively than were mapped preoperatively in both the parotid/preauricular (P = 0.0017) and mastoid/postauricular (P = 0.0047) regions. Thirty-two nodes were identified intraoperatively that were not mapped preoperatively in the planar lymphoscintigraphy group (n = 63), two of which were positive for micrometastatic disease. In contrast, there were no discrepancies between preoperative mapping and intraoperative identification of sentinel nodes in the SPECT-CT group (n = 17).Conclusions:SPECT-CT is more accurate than planar lymphoscintigraphy for the preoperative identification of draining sentinel lymph nodes in auricular melanoma. If SPECT-CT is not available, planar lymphoscintigraphy can also be used safely, but careful intraoperative evaluation, even in basins not mapped by lymphoscintigraphy, must be performed to avoid missed sentinel nodes.

Narrative review of patterns of lymphatic drainage in early-stage non-small cell lung cancer

: In non-small cell lung cancer (NSCLC), the presence of metastatic nodal disease has been shown to be the most important predictor of long-term disease-specific survival after surgical resection. In patients with early stage, node-negative NSCLC who undergo complete resection, the current standard of care, a significant portion have recurrence of disease within 24 months after surgery. This has raised interest in better understanding the lymphatic drainage of these cancers to determine the exact patterns of loco-regional spread, and whether sentinel lymph node (SLN) identification can be utilized to aid in management of these diseases. Anatomic studies that have attempted to map the lymphatic drainage of tumors from different locations within the lung have revealed patterns of direct mediastinal drainage, which may help explain the prevalence of skip metastases, which is the presence of N2 disease in the absence of N1 disease. This article will provide a narrative review of primary literature concerning the anatomy of the pulmonary lymphatic system, patterns of nodal metastasis in NSCLC as studied through various techniques (including blue dye, radiocolloid tracers, and near-infrared image-guided SLN mapping), and opportunities for improvement in our understanding of how lung tumors interact with the lymphatic system on a structural level.

Clinical application of indocyanine green fluorescence imaging in laparoscopic lymph node dissection for intrahepatic cholangiocarcinoma: A pilot study (with video)

BackgroundIntrahepatic cholangiocarcinoma is a highly lethal malignancy characterized by lymph node metastasis. This study aimed to evaluate the efficacy of indocyanine green fluorescence for visualization of lymphatic drainage and to assess its clinical application during laparoscopic lymph node dissection for intrahepatic cholangiocarcinoma. MethodsAll patients with intrahepatic cholangiocarcinoma who underwent laparoscopic left hepatectomy and lymph node dissection between October 2018 and January 2021 were reviewed. The patients were assigned to the indocyanine green group or non–intrahepatic cholangiocarcinoma group based on the staining technique used. ResultsOf 38 patients with left hemiliver intrahepatic cholangiocarcinoma, 20 underwent intrahepatic cholangiocarcinoma tracer-guided laparoscopic radical left hepatectomy; 12 procedures were successful (indocyanine green group). During the same period, 18 patients were treated with traditional laparoscopic resection (control group). Their intraoperative factors were comparable and there were no differences in the incidence or severity of their postoperative complications 30 days after surgery (P > .05). In the indocyanine green group, more lymph nodes were harvested (mean [range]: 7.0 [6.0–8.0] vs 3.5 [3.0–5.0], P < .001) and the proportion of confirmed pathologic lymph nodes was higher (75.0%, 66.7%–87.5% vs 40%, 33.3%–50.0%, P < .001). ICG staining was observed in all (12/12, 100%) patients in the intrahepatic cholangiocarcinoma group at stations 8 and 12, and 9 (9/12, 75%) and 10 (11/12, 91.7%) patients at Stations 13 and 7, respectively. ConclusionThe indocyanine green fluorescence imaging system is feasible, safe, and effective for tracing lymph nodes. It can be used to identify regional lymphatic drainage patterns and help define the scope of lymph node dissection in patients with intrahepatic cholangiocarcinoma.

Analysis of the Different Lymphatic Drainage Patterns during Sentinel Lymph Node Biopsy for Skin Melanoma

In the last two decades, studies of lymphoscintigraphy imaging in lymphatic mapping reported an extreme heterogeneity of skin lymphatic drainage of some skin area, in contrast with the previous scientific literature. The aim of this study was to investigate the presence of any correlations between the topographical location of cutaneous melanoma and the topographical location of sentinel lymph nodes. Data from 165 patients undergoing sentinel lymph node biopsy between January 2013 and May 2021 were analyzed, demonstrating that melanomas in the Lumbar region presented a significant more heterogeneous drainage by site than those in the Scapular region (p < 0.01) and that melanomas in the Subscapular region were significantly more heterogeneous by laterality (unilateral vs. bilateral) than those in the Scapular region (p < 0.05). Results of this study supported the evidence of multiple lymphatic drainage as regards the sentinel node biopsy performed in skin melanoma located on the dorsal subscapular region and lumbar region. For this reason, the association of preoperative lymphoscintigraphy with another imaging evaluation is needed in these critical cutaneous areas. Recent technical developments enabling fluorescence lymphography together with indocyanine green have significantly improved the visualization of lymphatic drainage patterns at a microscopic level. In the preoperative phase, any doubt can be resolved by associating the SPET-CT scan to lymphoscintigraphy, while during the intraoperative phase, an additional evaluation with indocyanine green can be performed in doubtful cases. The aim of the duplex lymphatic mapping (pre and/or intraoperative) is an accurate search of sentinel nodes, in order to reduce the rate of false negatives.

Contrast-Enhanced Ultrasound for Precise Sentinel Lymph Node Biopsy in Women with Early Breast Cancer: A Preliminary Study.

Background: Sentinel lymph node biopsy (SLNB), as a common method for axillary staging of early breast cancer, has gradually attracted people’s attention to the false-negative rate and postoperative complications. The aim of the study is to investigate the clinical value of preoperative contrast-enhanced ultrasound (CEUS) for intraoperative SLNB in early breast cancer patients. Methods: A total of 201 patients scheduled for SLNB from September 2018 to April 2021 were collected consecutively. Preoperative CEUS was used to identify sentinel lymph nodes (SLN) and lymphatic drainage in breast cancer patients. Results: The SLN identification rate of CEUS was 93.0% (187/201) and four lymphatic drainage patterns were found: single LC to single SLN (70.0%), multiple LCs to single SLN (8.0%), single LC to multiple SLNs (10.2%), and multiple LCs to multiple SLNs (11.8%). The Sen, Spe, PPV, NPV, AUC of CEUS, US and CEUS + US in diagnosis of SLNs were 82.7%, 80.4%, 73.8%, 87.4%, 0.815; 70.7%, 77.7%, 68.0%, 79.8%, 0.742; and 86.7%, 77.7%, 72.2%, 89.7%, 0.822, respectively. There was no statistically significant difference between the diagnostic performance of CEUS and CEUS + US (p = 0.630). Conclusions: CEUS can be used to preoperatively assess the lymphatic drainage patterns and the status of the SLNs in early breast cancer to assist precision intraoperative SLNB.

599 Intramammary Melanoma Micrometastasis Within A Silicone Implanted Breast

Abstract Case Summary Melanoma of the abdominal wall is not uncommon, and sentinel lymph nodes are usually located in the lymphatic drainage basins of the axilla or inguinal region. Less frequently, interval sentinel lymph nodes can be found along the lymphatic vessels between the primary cancer and nearest basin. We present the case of a 53-year-old female with silicone breast implants who underwent scar excision and sentinel lymph node biopsy for a 1mm Breslow thickness superficial spreading melanoma of the abdomen. Two lymph nodes were excised; both lying in the subcutaneous fat at the lateral aspect of the right breast capsule. Lymph node histology revealed a subcapsular melanoma deposit along with silicone lymphadenopathy in the sentinel node, and silicone lymphadenopathy in the second node. Whole body positron emission tomography (PET/CT) and magnetic resonance imaging (MRI) of the brain showed no evidence of metastases or implant rupture. Subsequent MRI breast revealed likely intracapsular implant rupture. The patient was offered removal of implants and remains under follow-up. The unusual location of the sentinel node in our patient highlights the possibility that previous breast augmentation may have altered the pattern of lymphatic drainage to the axilla. In addition, to our knowledge, this is the first reported case of silicone and melanoma deposits in a single sentinel node.

Does the pattern of lymphatic drainage influence the risk of nodal recurrence in trunk melanoma patients with negative sentinel lymph node biopsy?

BackgroundThere are conflicting data regarding the prognostic value of the lymphatic basin drainage pattern in melanoma patients and the evidence is scant in the setting of negative sentinel lymph node biopsy. ObjectiveTo investigate whether the pattern of lymphatic basin drainage influences the risk of nodal disease in patients with melanoma of the trunk and negative sentinel lymph node biopsy. MethodsA case series of patients with trunk melanoma and negative sentinel lymph node biopsy was retrospectively evaluated. Clinicopathological features, the pattern of lymphatic drainage and nodal, metastatic, and overall recurrence-free survival were reviewed. ResultsOf the 135 patients included, multiple lymphatic basin drainage was identified in 61 (45.2%). Ten of the 74 (13.5%) patients with single drainage developed nodal recurrence, compared with 2 of the 61 (3.6%) patients with multiple drainages (p = 0.04). Nodal recurrence-free survival was significantly longer in the group with multiple drainages than in the group with single drainage (175.6 vs. 138.7 months; p = 0.04). In multivariate analysis, single drainage was associated with a higher risk of nodal recurrence (HR = 4.54; p = 0.05). No significant differences in metastatic and overall recurrence-free survival were found between groups. Study limitationsRetrospective analysis, single-center study, small sample, detailed histopathologic information not always present. ConclusionsIn patients with trunk melanoma and negative sentinel lymph node biopsy, multiple lymphatic basin drainage may be an independent risk factor for nodal disease recurrence. This factor may help to identify patients with negative sentinel lymph node biopsy with a higher risk of nodal recurrence.

Lymphatic drainage map of the head and neck skin squamous cell carcinoma detected by sentinel lymph node biopsy.

Squamous cell carcinoma of the skin often affects the scalp and neck region and has a potential for complex lymphatic metastases. The aim of this study was to examine the pattern of lymphatic drainage that would enable better insight and prediction of lymphatic metastasis of head and neck squamous cell carcinoma (HNSCC) in relation to the anatomical localization of the primary process. A prospective analysis included 64 patients who underwent sentinel lymph node (SLN) biopsy. The biopsy was performed in patients with high-risk cutaneous head and neck squamous cell carcinoma between 2006 and 2010. SLNs in tumors of the forehead, temporal region, lateral cheek, and auricle were found in the cervical region at level II and parotid lymph nodes (p<0.001). In tumors of the nose, periorbital region, and postauricular tumors, SLNs were found in parotid lymph nodes (p<0.001), in tumors of the medial cheek in level I cervical lymph nodes and parotid lymph nodes (p=0.003). In tumors of the neck, SLNs were detected in the cervical region at level IV, whereas in tumors of the posterior scalp they were found in the occipital region (p<0.001). The results of SLN biopsy in high-risk cutaneous HNSCCs show the regularity of metastasis based on which a lymphatic drainage map can be constructed and thus potential metastatic sites depending on the primary tumor localization predicted.

39607 Mapping the Draining Lymph Nodes in Central Nervous System Malignancies

ABSTRACT IMPACT: We seek to determine which lymph nodes drain the human brain. OBJECTIVES/GOALS: Lymphatic vessels train lymphatic fluid from the central nervous system (CNS), but the specific lymph nodes that these vessels drain to remains unknown in humans. We intend on using technetium tilmanocept (TcTM)to map the draining lymph nodes of the CNSin humans. METHODS/STUDY POPULATION: Patients having a tumor resected are eligible for the trial. All patients will have TcTM injected intracranially after tumor resection. Six patients will be enrolled in Cohort 1 to define the time course of drainage to the lymph nodes. Patients in Cohort 1 will be imaged with planar LS within 7 hours of injection and the following day. Either 12 or 24 patients will be enrolled into Cohort 2 to localize the draining lymph nodes with SPECT-CT. The optimal imaging timepoint from Cohort 1 will be used for Cohort 2. Patients in Cohort 2 will be stratified depending on if their tumor is in the frontal, parietal, occipital, or temporal lobe. RESULTS/ANTICIPATED RESULTS: We anticipate that we will detect TcTMin the deep cervical lymph nodes after injection into the brain. It is unclear exactly which lymph nodes the tracer will go to. We hypothesize that the results among patients will be similar, but interindividual variation is a possibility. Furthermore, patients with disease in different lobes of the brain may have different lymph drainage patterns. DISCUSSION/SIGNIFICANCE OF FINDINGS: We seek to answer a fundamental question of human anatomy: what lymph nodes drain the human brain? Additionally, knowing which nodes drain the human brain could shape future research of immunotherapy in patients with brain cancer or autoimmune disease such as multiple sclerosis.

Lymphatic drainage of lung cancer follows an intersegmental pathway within the visceral pleura

ObjectivesLung cancer tumors are known to be highly lymphophilic. There are two different pattern of lymphatic drainage of the lung: one peribronchial lymphatic pathway, and another one within the visceral pleura which appears to be more intersegmental than the peribronchial pathway. We aimed to assess the prevalence of an intersegmental pathway in the lymphatic drainage of lung tumors within the visceral pleura and determine potential influential factors. MethodsIn this prospective study, we included all patients for whom a major pulmonary resection (lobar) was indicated and performed for suspected or proven lung cancer. An immediate ex-vivo evaluation of the surgical specimen after resection was conducted by trans-pleural injection of blue dye within the tumor. The pathways followed by the lymphatic vessels under the visceral pleura were assessed to define the occurrence of an intersegmental pathway, which was defined by the presence of blue dye within the lymphatic vessel crossing to a neighboring pulmonary segment, distinct from the tumorous segment. ResultsFifty-three patients met the inclusion criteria and were assessed over a three-year period. Lymphatic drainage within the visceral pleura followed an intersegmental pathway in 35 of 53 patients (66 %). When the lymphatic drainage of the tumor was intersegmental, it drained in a single other segment in 21/35 cases and two or more in 14/35 cases. Logistic regression with multivariate analysis showed a peripheral location of the tumor to be a risk factor for the intersegmental pathway of visceral pleura lymphatic drainage (OR = 0.87 [079−0.95], p = 0.003). ConclusionThese results confirm that lymphatic drainage of lung cancer in the visceral pleura appears to largely follow an intersegmental pathway, especially when the tumor is peripheral, close to the visceral pleura.

Abstract PS14-21: Refining loco-regional therapy for inflammatory breast cancer protocol in progress

Abstract Background: Inflammatory breast cancer (IBC) is the most aggressive locally advanced breast cancer subtype. It is associated with loco-regional recurrence rates of 12-25%, and neoadjuvant chemotherapy (NAC) followed by modified radical mastectomy and comprehensive chest wall and regional nodal radiotherapy remain the standard of care. As has been demonstrated in non-IBC, achievement of pathologic complete response (pCR) has been shown to be associated with improved loco-regional control, recurrence-free and overall survival. Advances in NAC for IBC have resulted in improved pCR rates in both the breast and the axilla, with overall axillary pCR rates of approximately 30%, reaching as high as 67% in patients with HER2-positive disease receiving HER2-directed therapy. Hypothesis: Sentinel lymph node biopsy (SLNB) may be feasible in IBC patients who experience a good clinical and pathologic response in the axilla to NAC. Primary Objective: To evaluate the sentinel lymph node (SLN) identification rate in stage III IBC patients who experience cN0 status at completion of NAC. Secondary Objective: To assess the incidence of lymphedema following standard local-regional therapy for IBC. Methods and Study procedures: In this feasibility study, 50 patients with cT4dN0-2M0 IBC will be enrolled in order to evaluate 40 patients whose axillary nodal status becomes cN0 upon completion of NAC. All patients will undergo a research breast biopsy and lymphoscintigram pre and post NAC to evaluate lymphatic drainage patterns and patency of breast and axillary lymphatics. Post NAC lymphoscintigraphy will be appropriately timed for pre-operative SLN mapping and all patients will undergo SLNB using dual tracers (Tc99 Sulfur colloid and blue dye) with immediate axillary lymph node dissection (ALND), at the time of mastectomy. The patient-reported Lymphedema Symptom Intensity and Distress Survey (LSIDS-A) will be collected at 6 timepoints. Patients will be followed for 2 years post-surgery for oncologic outcomes. Correlatives: We plan to evaluate genetic and phenotypic heterogeneity in IBC and to assess markers of angiogenesis and lymph-angiogenesis associated with IBC, as well as to explore immunologic aspects of the tumor microenvironment and their association with pCR. Statistics: The identification rate will be calculated as number of patients in whom SLNs were successfully identified over the number of patients with cN0 disease after NAC in whom SLN mapping was attempted. Using a Simon two-stage design (α=.10, β=.10), a SLN identification rate of ≥90% would result in considering this procedure feasible whereas an identification rate of ≤75% (null hypothesis) would lead to the conclusion that it is not feasible. In the first stage, if greater than 18 of 25 patients have SLNs identified, then a total of 40 patients will be enrolled. If fewer than 33 of 40 patients have SLN identified, then the null hypothesis is rejected. Citation Format: Faina Nakhlis, Meredith Regan, Heather Jacene, Beth Harrison, Jennifer Bellon, Jean Landry, Eren Yeh, Elizabeth Mittendorf, Beth Overmoyer, Tari King. Refining loco-regional therapy for inflammatory breast cancer protocol in progress [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS14-21.

Comparing unilateral vs. bilateral neck management in lateralized oropharyngeal cancer between surgical and radiation oncologists: An international practice pattern survey

Management of the neck in oropharyngeal carcinoma varies due to a lack of clarity of patterns of lymphatic drainage and concern of failure in the contralateral neck. With recent advances in transoral surgical techniques, surgical management has become increasingly prevalent as the primary treatment modality. We compare international practice patterns between surgical and radiation oncologists. A survey of neck management practice patterns was developed and pilot tested by 6 experts. The survey comprised items eliciting the nature of clinical practice, as well as patterns of neck management depending on extent of nodal disease and location and extent of primary site disease. Proportions of surgical and radiation oncologists treating the neck bilaterally were compared using the chi-squared statistic. Two-hundred and twenty-two responses were received from 172 surgical oncologists, 44 radiation oncologists, 3 medical oncologists, and 3 non-oncologists from 32 different countries. For tongue base cancers within 1cm of midline (67% vs. 100%, p<0.001), and for tonsil cancers with extension to the medial 1/3 of the soft palate (65% vs. 100%, p<0.001) or tongue base (77% vs. 100%, p<0.001), surgical oncologists were less likely to treat the neck bilaterally. For isolated tonsil fossa cancers with no nodal disease, both surgical and radiation oncologists were similarly likely to treat unilaterally (99% vs. 97%, p=NS). However, with increasing nodal burden, radiation oncologists were more likely to treat bilaterally for scenarios with a single node<3cm (15% vs. 2%, p<0.001), a single node with extranodal extension (41% vs. 18%, p<0.001), multiple positive nodes (55% vs. 23% p<0.001), and node(s)>6cm (86% vs. 33%, p<0.001). For tumors with midline extension, even with a negative PET in the contralateral neck, the majority of surgical and radiation oncologists would still treat the neck bilaterally (53% and 84% respectively). The present study demonstrates significant practice pattern variability for management of the neck in patients with lateralized oropharyngeal carcinoma. Surgical oncologists are less likely to treat the neck bilaterally, regardless of tumor location or nodal burden. Even in the absence of disease in the contralateral neck on imaging, them majority of practitioners are likely to treat bilaterally when the disease approaches midline.

Is skipped nodal metastasis a phenomenon of cutaneous melanoma?

Background and MethodsSkipped nodal metastasis (SNM) is a recognized phenomenon of visceral cancers when metastases bypass the regional basin and skip to a distant nodal basin without evidence of distant metastases. Its occurrence is undocumented in cutaneous melanoma patients but of potential prognostic significance. We therefore assessed the frequency of SNM in a large series of patients with limb melanomas. Patients and MethodsWe studied melanoma patients attending a tertiary oncology hospital in northwest England using two approaches. First, we systematically searched medical records of an unselected patient sample treated 2002–2015, and second, we studied lymphoscintigrams of all patients with limb melanoma who underwent sentinel node biopsy 2008–2019. ResultsOf 672 melanoma patients whose clinical records were examined, 16 had regional nodal metastases without apparent visceral spread and one appeared to have SNM but further scans were uncovered that showed concurrent pulmonary metastases. Of 667 limb melanoma patients with lymphoscintigrams, 7 showed dual lymphatic drainage patterns to distal as well as regional nodal basins, but none had micro-metastases solely in the distant basin. ConclusionOccurrence of SNM in cutaneous melanoma is highly unlikely.

Liver lymphatic drainage patterns follow segmental anatomy in a murine model

The liver’s cellular functions are sustained by a hierarchical, segmentally-organized vascular system. Additionally, liver lymphatic vessels are thought to drain to perihepatic lymph nodes. Surprisingly, while recent findings highlight the importance of organ-specific lymphatics, the functional anatomy of liver lymphatics has not been mapped out. In literature, no segmental or preferential lymphatic drainage patterns are known to exist. We employ a novel murine model of liver lymphangiography and in vivo microscopy to delineate the lymphatic drainage patterns of individual liver lobes. Our data from blue dye liver lymphangiography show preferential lymphatic drainage patterns: Right lobe mainly to hepatoduodenal ligament lymph node 1 (LN1); left lobe to hepatoduodenal ligament LN1 + LN2 concurrently; median lobe showed a more variable LN1/LN2 drainage pattern with increased (sometimes exclusive) mediastinal thoracic lymph node involvement, indicating that part of the liver can drain directly to the mediastinum. Upon ferritin lymphangiography, we observed no functional communication between the lobar lymphatics. Altogether, these results show the existence of preferential lymphatic drainage patterns in the murine liver. Moreover, this drainage can occur directly to mediastinal lymph nodes and there is no interlobar lymphatic flow. Collectively, these data provide the first direct evidence that liver lymphatic drainage patterns follow segmental anatomy.

Assessment of diagnostic value of fluorescent lymphography-guided lymphadenectomy for gastric cancer.

Indocyanine green fluorescent lymphography helps visualize the lymphatic drainage pattern in gastric cancer; however, it is unknown whether fluorescent lymphography visualizes all metastatic lymph nodes. This study aimed to evaluate the sensitivity of fluorescent lymphography to detect metastatic lymph node stations and lymph nodes and the risk of false-negative findings. Patients with clinical T1-4a gastric cancer were included. Indocyanine green was peritumorally injected the day prior to surgery by endoscopy. Gastrectomy with systematic D1+ or D2 lymphadenectomy was performed. Stations and lymph nodes were retrieved at the back-table using near-infrared imaging and classified as "fluorescent" or "non-fluorescent" and later matched with histopathological findings. Among 592 patients who underwent minimally invasive gastrectomy from September 2013 until December 2016, lymph node metastases were present in 150. The sensitivity of fluorescent lymphography in detecting all metastatic lymph node stations was 95.3% (143/150 patients), with a false-negative rate of 4.7% (7/150 patients) and the sensitivity in detecting all metastatic lymph nodes was 81.3% (122/150 patients). The negative predictive value was 99.3% for non-fluorescent stations and 99.2% for non-fluorescent LNs. For detecting all metastatic LN stations, subgroup analysis revealed 100% sensitivity for pT1a, 96.8% for pT1b, 100% for pT2, 91.3% for pT3, and 93.6% for pT4a tumors. Fluorescent lymphography-guided lymphadenectomy can be a useful method for radical lymphadenectomy by facilitating the complete dissection of all potentially positive LN stations. Fluorescent lymphography-guided lymphadenectomy appears to be a reasonable alternative to conventional systematic lymphadenectomy for gastric cancer.

Sentinel lymph node detection in oral cancer: a within-patient comparison between [99mTc]Tc-tilmanocept and [99mTc]Tc-nanocolloid

PurposeSentinel lymph node (SLN) biopsy has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC). [99mTc]Tc-tilmanocept may be of benefit in OSCC with complex lymphatic drainage patterns and close spatial relation to SLNs.MethodsA prospective within-patient evaluation study was designed to compare [99mTc]Tc-tilmanocept with [99mTc]Tc-nanocolloid for SLN detection. A total of 20 patients with early-stage OSCC were included, who underwent lymphoscintigraphy with both tracers. Both lymphoscintigraphic images of each patient were evaluated for SLN detection and radiotracer distribution at 2–4 h post-injection.ResultsThe injection site’s remaining radioactivity was significantly lower for [99mTc]Tc-tilmanocept (29.9%), compared with [99mTc]Tc-nanocolloid (60.9%; p < 0.001). Radioactive uptake in SLNs was significantly lower for [99mTc]Tc-tilmanocept (1.95%) compared with [99mTc]Tc-nanocolloid (3.16%; p = 0.010). No significant difference was seen in SLN to injection site ratio in radioactivity between [99mTc]Tc-tilmanocept (0.066) and [99mTc]Tc-nanocolloid (0.054; p = 0.232). A median of 3.0 and 2.5 SLNs were identified with [99mTc]Tc-tilmanocept and [99mTc]Tc-nanocolloid, respectively (p = 0.297). Radioactive uptake in higher echelon nodes was not significantly different between [99mTc]Tc-tilmanocept (0.57%) and [99mTc]Tc-nanocolloid (0.86%) (p = 0.052). A median of 2.0 and 2.5 higher echelon nodes was identified with [99mTc]Tc-tilmanocept and [99mTc]Tc-nanocolloid, respectively (p = 0.083).Conclusion[99mTc]Tc-tilmanocept had a higher injection site clearance, but at the same time a lower uptake in the SLN, resulting in an SLN to injection site ratio, which was not significantly different from [99mTc]Tc-nanocolloid. The relatively low-radioactive uptake in SLNs of [99mTc]Tc-tilmanocept may limit intraoperative detection of SLNs, but can be overcome by a higher injection dose.

Near-Infrared Fluorescent Image-Guided Lymphatic Mapping in Esophageal Squamous Cell Carcinoma.

Recently, the feasibility of near-infrared (NIR) image-guided sentinel lymph node (SLN) mapping has been tested in patients with gastrointestinal cancer. The aim of this study is to investigate whether SLN mapping can be used to identify mediastinal lymph node metastases during minimally invasive esophagectomy and explore the lymphatic drainage pattern of esophageal squamous cell carcinoma (ESCC) using NIR fluorescent imaging. A total of 21 patients diagnosed with cT1-3 stage ESCC were enrolled. Patients received submucosal injection of indocyanine green diluted with sodium chloride (0.9%) at the start of the esophagectomy procedure followed by NIR mapping. Thoracoscopic-assisted McKeown esophagectomy with NIR imaging was successfully performed in all patients. The detection rate and number of NIR+ lymph nodes were 95.2% (20/21) and 4.0 (2.0-6.5), respectively. The accuracy, false-negative rates, and negative predictive value were 100% (10 of 10 cases), 0% (0 of 4), and 100% (6 of 6), respectively, for pT1/T2 diseases; and 80.0% (8 of 10), 40% (2 of 5), and 71.4% (5 of 7), respectively, for pT3 diseases. The NIR+ region was the most commonly detected in the right recurrent laryngeal nerve (80%), and the NIR+ region was identified in the upper mediastinal zone in 20 patients. Evaluation of the lymphatic drainage pattern and the application of sentinel lymph node in ESCC with real-time NIR imaging could be effective, especially in pT1/2 disease. NIR imaging-guided SLN navigation appears to be a clinically beneficial less-invasive method for treating ESCC.

Impact of indocyanine green‐guided extended pelvic lymph node dissection during robot‐assisted radical prostatectomy

To evaluate the effectiveness of indocyanine green-guided extended pelvic lymph node dissection during robot-assisted radical prostatectomy for intermediate- to high-risk prostate cancer. After institutional review board approval, between July 2017 and December 2018, we carried out 100 indocyanine green-guided extended pelvic lymph node dissections in patients with localized intermediate- and high-risk prostate cancer, using the Firefly (Novadaq Technologies, Mississauga, ON, Canada) and da Vinci Xi surgical system (Intuitive Surgical, Sunnyvale, CA, USA). Indocyanine green was injected transrectally using ultrasound sonography before each surgery. Then, lymphatic drainage patterns and pathological findings were recorded. Lymphatic drainage routes were successfully determined in 91 right-sided and 90 left-sided cases. Five main lymphatic pathways and sites were identified: (i) an internal route (57%); (ii) a lateral route (50%); (iii) a presacral route (20%); (iv) a paravesical artery site (20%); and (v) a pre-prostatic site (5%). Lymph node metastasis was positive in 15 patients, with 44 pathologically confirmed metastatic lymph nodes. Metastatic fluorescent lymph nodes were found in 15 out of 44 lymph nodes (34.1%). For sentinel lymph node identification, the 34% sensitivity and 64.8% specificity rates were detected in regard to identification of lymph node metastasis. Lymphatic drainage patterns from the prostate can be identified and classified using indocyanine green-guided extended pelvic lymph node dissections. Although the direct role of fluorescent lymph nodes in sentinel lymph node identification appears to be limited, the identification of lymphatic pathways could contribute to high-quality extended pelvic lymph node dissection during robot-assisted radical prostatectomy.

Accuracy of sentinel lymph node biopsy in invasive lobular carcinoma of the breast.

e12604 Background: The safety of the sentinel lymph node biopsy procedure (SLNB) in the surgical management of breast cancer relies upon a false negative rate (FNR) being less than 10%. The accuracy of SLNB in invasive lobular carcinoma (ILC), the second most common type of breast cancer, has not been evaluated. Because of high rates of false negative imaging and the diffuse growth pattern in ILC, less accurate pre-operative staging and a potentially unreliable lymphatic drainage pattern may impact the accuracy of SLNB in this tumor type. We therefore sought to characterize the accuracy of SLNB in a cohort of patients with ILC. Methods: We queried an institutional database of 707 patients with ILC and identified 196 patients who underwent SLN mapping with excision of both sentinel and non-sentinel nodes. A false negative was defined as having negative sentinel lymph nodes and a positive non-sentinel node. We calculated the FNR and sensitivity of SLNB and evaluated clinicopathologic variables. Results: Of 196 cases, 183 were clinically node-negative, 9 were clinically node-positive, and 4 had unknown clinical node status. Of the 183 clinically node-negative patients, 69 (37.7%) patients had node-positive disease at surgery. Overall, 7 of 196 cases had false negative SLNB, yielding an FNR of 8.97%. The sensitivity of SLNB was 91%. Patients with a false negative SLNB were significantly older than patients without (mean age 63 versus 54.7 years, p = 0.041). Significantly fewer sentinel and non-sentinel nodes were removed in women aged 50 years or older compared to those under 50 (1.9 vs. 2.5 sentinel nodes, p = 0.0158; 4.7 vs. 7.9 non-sentinel nodes, p = 0.0077). There were no differences in tumor receptor subtype, grade, stage, presence of lymphovascular invasion, or receipt of neoadjuvant therapy in those with a false negative SLNB compared to those without. Conclusions: The high rate of nodal positivity in clinically node negative patients highlights the challenges of clinical nodal assessment in ILC. Despite this, the SLNB procedure had a FNR that fell within the acceptable range, supporting its use in ILC. The relationship between number of sentinel nodes removed and FNR deserves further study, particularly in older women where extent of nodal surgery continues to decline.