Sentinel Lymph Node Localization Research Articles

Abstract PO1-22-11: Use of magnetic tracer and magnetic resonance imaging for sentinel lymph node detection after breast cancer recurrence and previous axillary surgery: The SentiRecur feasibility study

Abstract Background: Preoperative imaging increases the chance of finding the sentinel lymph node (SLN) in patients with previous axillary surgery. Current clinical routine for preoperative localization is Technetium (Tc99) and lymphoscintigraphy. An alternative method has been proposed using superparamagnetic iron oxide nanoparticles (SPIO) and non-contrast enhanced magnetic resonance imaging (MRI) of the axillae. In this feasibility study, SPIO+MRI was used in parallel with Tc99+scintigraphy for SLN localization. Methods: Twenty patients with recurrent breast cancer and previous axillary surgery at Sahlgrenska and Linkoping University Hospitals scheduled for SLN-biopsy will be included. All patients received Tc99+scintigraphy as per standard practice. In addition, a SPIO injection and bilateral axillary MRI was performed up to four weeks before surgery. Both preoperative and perioperative SLN-detection rates were studied. Rates and number of concordant SLNs were presented as percentages. Results: So far, ten patients received both SPIO+MRI and Tc99+scintigraphy. The SLN-detection rates per patient were 70% (7/10) for SPIO+MRI and 50% (5/10) for Tc99+scintigraphy, respectively. The perioperative SLN-detection rates per patient were 60% (6/10) for SPIO using the magnetic probe (SentiMagTM) and 30% (3/10) for Tc99 using a gamma-probe. In total, eleven SLNs were detected with SentiMag and four with gamma-probe. Of all SLNs, only four (36%) contained both SPIO and Tc99. Conclusion(s): Although preliminary, the results suggest that Tc99+scintigraphy may be replaced by the magnetic technique for detecting SLNs after earlier axillary surgery. The magnetic technique enables logistic advantages as tracer injection and SLN identification during a wider time frame. Table 1. Sentinel lymph node detection in patients with recurrent breast cancer Table 1. Sentinel lymph node detection in patients with recurrent breast cancer Citation Format: Eva VikhePatil, Kian Chin, Amalia SegerbardPlanoudis, Carlos Dussan, Henrik Leonhardt, Pontus Zaar, Pantelis Gialis, Fredrik Wärnberg. Use of magnetic tracer and magnetic resonance imaging for sentinel lymph node detection after breast cancer recurrence and previous axillary surgery: The SentiRecur feasibility study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-22-11.

Sentinel lymph node biopsy experience in squamous cell carcinoma of the oral mucosa сT1–2N0M0

Introduction. Head and neck cancer is the 7th most common malignancy worldwide; squamous cell carcinoma of the oral mucosa are almost a third of tumors of that localization. Metastatic lesions of the neck lymph nodes are an unfavorable prognostic factor for malignant tumors of that location since it is associated with a 50 % decrease in overall survival. In this regard, the detection of metastases to the neck lymph nodes is an important component of high-quality oncological care for patients with that pathology.Aim. To evaluate the efficiency of sentinel lymph node biopsy in squamous cell carcinoma of cavity of mouth mucosa cT1–2N0М0.Materials and methods. 72 patients were included in trial at the age from 21 to 74 (mean 57.3) with confirmed squamous cell carcinoma of cavity of mouth mucosa cT1–2N0М0. No evidence of regional metastasis, by preoperative examination, including ultrasound, computed tomography with intravenous contrast was observed. All patients received radioisotope research to determine localization of sentinel lymph nodes, and then biopsy of that nodes was performed. Before obtaining information about the status of the sentinel lymph node, radical neck dissection was not performed. Pathology report with immunohistochemical investigation was performed by pathologist of A. F. Tsyb Medical Radiological Research Center – branch of the National Medical Research Radiological Center, Ministry of Health of Russia.Results. When assessing efficiency of sentinel lymph node method, true positives results (detection of metastasis in sentinel lymph node) were achieved in 3 (4.17 %) out of 72 cases. Follow up time was from 1 to 69 months. Among those cases, where metastasis in sentinel lymph nodes were not detected, relapse in regional lymph nodes was developed in 3 (4.35 %) out of 69 cases. Radical neck dissection was performed in cases with metastasis in sentinel lymph nodes. The specificity of method was 95 %, the predictive value of a negative result was 0.04.Conclusion. Sentinel lymph neck node biopsy is an effective method of subclinical locoregional metastases detection in cancer of oral mucosa cT1–2N0M0. In our study of sentinel lymph neck node biopsy, oncological outcomes were comparable to radical neck dissection, with fewer postoperative complications.

Risk factors associated with false negative rate of sentinel lymph node biopsy in endometrial cancer: a systematic review and meta-analysis.

Currently, sentinel lymph node biopsy (SLNB) is increasingly used in endometrial cancer, but the rate of missed metastatic lymph nodes compared to systemic lymph node dissection has been a concern. We conducted a systematic review and meta-analysis to evaluate the false negative rate (FNR) of SLNB in patients with endometrial cancer and to explore the risk factors associated with this FNR. Three databases (PubMed, Embase, Web of Science) were searched from initial database build to January 2023 by two independent reviewers. Studies were included if they included 10 or more women diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I or higher endometrial cancer, the study technique used sentinel lymph node localization biopsy, and the reported outcome metrics included false negative and/or FNR. Two authors independently reviewed the abstracts and full articles. The FNR and factors associated with FNR were synthesized through random-effects meta-analyses and meta-regression. We identified 62 eligible studies. The overall FNR for the 62 articles was 4% (95% CL 3-5).There was no significant difference in the FNR in patients with high-risk endometrial cancer compared to patients with low-risk endometrial cancer. There was no difference in the FNR for whether frozen sections were used intraoperatively. The type of dye used intraoperatively (indocyanine green/blue dye) were not significantly associated with the false negative rate. Cervical injection reduced the FNR compared with alternative injection techniques. Indocyanine green reduced the FNR compared with alternative Tc-99m. Postoperative pathologic ultrastaging reduced the FNR. Alternative injection techniques (other than the cervix), Tc-99m dye tracer, and the absence of postoperative pathologic ultrastaging are risk factors for a high FNR in endometrial cancer patients who undergo SLNB; therefore, we should be vigilant for missed diagnosis of metastatic lymph nodes after SLNB in such populations. http://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023433637.

Use of Indocyanine Green Near-Infrared Imaging for Sentinel Lymph Node Biopsy in Early Oral Squamous Cell Carcinoma: A Pilot Study

PurposeThe current established technique for sentinel lymph node (SLN) biopsy is preoperative injection of 99mtechnetium-labeled nanosized colloids (99mTc) followed by single photon emission computed tomography and standard computed tomography (SPECT/CT) with subsequent intraoperative gamma probe-guided excision of the SLN. It is however time and resource consuming, causes radiation exposure and morbidity for the patient as the injection is done in the awake patient. Recently near-infrared imaging with indocyanine green (ICG) gained importance in SLN biopsy as a faster and more convenient technique. The objective of our study was to investigate the feasibility of SLN biopsy using ICG-imaging in early oral squamous cell carcinoma (OSCC).MethodsSingle-centre pilot study of five patients with early-stage OSCC. For all patients, both techniques (99mTc and ICG) were performed. We injected 99mTc preoperatively in the awake patient, followed by SPECT/CT imaging. Intraoperatively ICG was injected around the primary tumor. Then the neck incision was performed according to the SPECT/CT images and SLN were detected by using a gamma probe and near-infrared fluorescence imaging of the ICG-marked lymph nodes intraoperatively. The excised lymph nodes were sent to histopathological examination according to the SLN dissection protocol.ResultsIn all five patients sentinel lymph nodes were identified. A total of 7 SLN were identified after injection of 99mTc, imaging with SPECT/CT and intraoperative use of a gamma probe. All these SLN were fluorescent and visible with the ICG technique. In two patients, we could identify additional lymph nodes using the ICG technique. Pathological analysis demonstrated occult metastasis in two of the cases.ConclusionsOur study shows that ICG-guided SLN biopsy is a feasible technique, especially in combination with conventional radioisotope method and may help for intraoperative localization of SLN. Validation studies with bigger patient cohorts are needed to prove our results.

Sentinel Node Mapping in Ovarian Tumors: A Study Using Lymphoscintigraphy and SPECT/CT.

Ovarian cancer in the early stage requires a complete surgical staging, including radical lymphadenectomy, implying subsequent risk of morbidity and complications. Sentinel lymph node (SLN) mapping is a procedure that attempts to reduce radical lymphadenectomy-related complications and morbidities. Our study evaluates the feasibility of SLN mapping in patients with ovarian tumors by the use of intraoperative Technetium-99m-Phytate (Tc-99m-Phytate) and postoperative lymphoscintigraphy using tomographic (single-photon emission computed tomography/computed tomography (SPECT/CT)) acquisition. Thirty-two patients with ovarian mass participated in this study. Intraoperative injection of the radiopharmaceutical was performed just after laparotomy and before the removal of tumor in utero-ovarian and suspensory ligaments of the ovary just beneath the peritoneum. Subsequently, pelvic and para-aortic lymphadenectomy was performed for malignant masses, and the presence of tumor in the lymph nodes was assessed through histopathological examination. Conversely, lymphadenectomy was not performed in patients with benign lesions or borderline ovarian tumors. Lymphoscintigraphy was performed within 24 hr using tomographic acquisition (SPECT/CT) of the abdomen and pelvis. Final pathological examination showed 19 patients with benign pathology, 5 with borderline tumors, and 6 with malignant ovarian tumors. SPECT/CT identified SLNs in para-aortic-only areas in 6 (20%), pelvic/para-aortic areas in 14 (47%), and pelvic-only areas in 7 (23%) cases. Notably, additional unusual SLN locations were revealed in perirenal, intergluteal, and posterior to psoas muscle regions in three patients. We were not able to calculate the false negative rate due to the absence of patients with involved lymph nodes. SLN mapping using intraoperative injection of radiotracers is safe and feasible. Larger studies with more malignant cases are needed to better evaluate the sensitivity of this method for lymphatic staging of ovarian malignancies.

The Sentinel Node and Occult Lesion Localization (SNOLL) Technique Using a Single Radiopharmaceutical in Non-palpable Breast Lesions.

In order to perform a full surgical resection on non-palpable breast lesions, a current method necessitates correct intraoperative localization. Additionally, because it is an important prognostic factor for these patients, the examination of the lymph node status is crucial. The aim of this study was to evaluate the efficiency of the sentinel node and occult lesion localization (SNOLL) technique in localizing nonpalpable breast lesions together with sentinel lymph node (SLN) using a single radiotracer, that is, nanocolloid particles of human serum albumin (NC) labeled with technetium-99m (99mTc). 39 patients were included, each having a single non-palpable breast lesion and clinically no evidence of axillary disease. Patients received 99mTc- NC intratumorally on the same day as surgery under the guidance of ultrasound. Planar and single-photon emission computed tomography/computed tomography lymphoscintigraphy were performed to localize the breast lesion and the SLN. The occult breast lesion and SLN were both localized using a hand-held gamma-probe, which was also utilized to determine the optimal access pathway for surgery. In order to ensure a radical treatment in a single surgical session and reduce the amount of normal tissue that would need to be removed, the surgical field was checked with the gamma probe after the specimen was removed to confirm the lack of residual sources of considerable radioactivity. Breast lesions were successfully localized and removed in all patients. Pathological findings revealed breast carcinoma in 11/39 patients (28%) and benign lesions in 28 (72%). Axillary SLNs were detected in 31/39 (79.5%) patients. The metastatic involvement of SLN was only seen in two cases. While the identification rate of the SNOLL technique performed with an intratumoral injection of 99mTc-NC as the sole radiotracer in non-palpable breast lesions was great, it was not fully satisfactory in SLNs.

Intranipple injection with methylene blue for tracing axillary sentinel lymph nodes in rats: A preliminary feasibility study

Background and purpose: Investigate the feasibility of intranipple injection (INN) of methylene blue dye (MB) for tracing the axillary sentinel lymph node (SLN) in rats, to provide different injection methods for finding SLN injection tracers and offer an experimental basis for specific localization of SLN. Methods: Eleven Sprague-Dawley female rats with body masses of 150-400g. Ten rats were randomly selected to use the third pair of mammary glands as the tracer injection site, and the left side was injected with MB (0.05 mL, 1% concentration) by intracutaneous injection of areola (IAA), while the right side was injected with MB(0.05 mL, 1% concentration) by INN. After 5 minutes, the rats were dislocated and dissected, and the blue-stained SLNs were found and recorded, The effectiveness evaluation was based on the number and rate of detection of SLNs as indicators, and the differences between the indicators of the two injection methods of IAA and INN were compared and analyzed. The safety evaluation was based on whether the nipple showed blood flow disorders and necrosis after MB injection by INN in the remaining 1 rat as the criteria. The data were stored and analyzed using Microsoft Excel and SPSS 25.0 statistical software. Νon-normally distributed measurement data were expressed as M (Q1, Q3) and compared by rank sum test, and count data were expressed as cases or percentages and compared by 2 test. p < 0.05 was considered a statistically significant difference. Results: (i)100% (10/10) detection rate of SLNs by applying MB to both INN and IAA modalities;(ii) median number of SLNs detection was 2.0 (1.0,2.0) vs. 1.5 (1.0,2.0) for INN and IAA, respectively (P=0.66), and the difference was not statistically significant;(iii) No nipple necrosis was observed for 4 consecutive days after INN with MB. Conclusion: Tracer detection of SLNs by INN injection in rats is feasible, and the detection rate of SLNs by INN is the same as that of IAA; there is no significant difference in the median number of detected SLNs between the two injection methods. No nipple necrosis was observed after INN with MB.

SURGICAL TREATMENT OF ADVANCED PALMOPLANTAR MELANOMA

Aim:
 Palmoplantar melanoma is a rare and aggressive subtype of malignant melanoma. Not like other subtypes, sunlight is not the primary etiologic factor. We aim to expand the knowledge on this rare and neglected malignant melanoma subtype and add our findings to the literature. 
 Materials and Methods:
 Malignant Melanoma patients admitted to our hospital between 2008 and 2020 were retrospectively analyzed. Twenty-seven patients with plantar and one with palmar melanoma were identified and included in our study. Data about gender, age at the diagnosis, histopathological features, sentinel lymph node localization, performed surgeries, sentinel lymph node biopsy (SLNB) and regional lymph node dissection results, recurrence, survival time, primary tumor localization, and systemic metastases were collected. 
 Results:
 26 plantar and one palmar melanoma patients were operated on in this period. Six patients died during follow-up. Twenty-three patients were treated with wide excisions, and four were treated with amputations. The defect was reconstructed with a skin graft in all cases with excisions. In 6 patients with suspicious lymph nodes in the preoperative imaging, lymph node dissection was added to the treatment. Other patients had sentinel lymph node biopsies and continued with dissection if a metastatic node was encountered. 
 Conclusion:
 Our findings are congruent with the current literature. Skin grafting may enhance the success of palmoplantar melanoma follow-up and demands attention.

A prospective audit to assess the feasibility of sentinel lymph node biopsy and/or low axillary sampling in clinicoradiologically node-negative axilla for early breast carcinoma

Background: Sentinel lymph node (SLN) dissection was designed to minimize side effects of lymph node surgery but still offer outcomes of axillary lymph node dissection. Aims and Objectives: Our study is designed to determine whether SLN resection achieves the same therapeutics outcome as complete axillary dissection but with fewer side effects for node-negative axilla in clinicoradiologically operable breast cancer patients. Materials and Methods: Duration-based prospective observational study was carried out at the General Surgery and Surgical Oncology Department at Government Medical College and Hospital, Aurangabad with a duration of 2 ½ years from July 2019 to January 2022. A total of 36 patients of breast cancers with stages T1-T2, N0 with clinically and radiologically negative axilla from July 2019 to January 2022 duration were included in our study. Results: When the histopathological status of axillary lymph nodes was compared to the histopathology of SLNs it was seen that out of 36 patients, the histopathology of sentinel node was positive in 10 patients (10/36) however the rest of the axilla was positive in 6 cases and negative in 4 cases and the histopathology sentinel node was negative in 26 patients out of 36 cases (26/36) however the rest of the axilla was also negative in 24 cases and positive in 2 cases. Conclusion: SLN biopsy using methylene blue dye alone is a highly reliable and predictable technique to stage the axilla in breast cancer patients as this study shown a low false-negative rate (7.69%). This technique may help to avoid complete axillary lymph node dissection in sentinel node-negative patients thereby minimizing the morbidity of axillary lymph node dissection. This study demonstrates that sentinel node localization is possible with methylene blue dye alone.

P056 Correlation between primary subsite and respective sentinel node location in head and neck melanoma – Identifying a predictable lymphatic drainage and reconstructive approach

P056 Correlation between primary subsite and respective sentinel node location in head and neck melanoma – Identifying a predictable lymphatic drainage and reconstructive approach

Comparison of indocyanine green-near-infrared fluorescence guided and traditional mediastinal lymphadenectomy during radical esophagectomy: A randomized controlled trial

BackgroundThe extent of lymph node dissection during radical esophagectomy remains a controversial topic. Thus, this study mainly aimed to explore the location of sentinel lymph nodes in esophageal squamous cell carcinoma and the application value of the indocyanine green–near-infrared fluorescence system in lymphadenectomy. MethodsThis randomized controlled clinical trial (ClinicalTrials.gov, NCT04615806) included 42 participants without neoadjuvant therapy who were lymph node negative based on positron emission tomography/computed tomography findings. Traditional esophagectomy with indocyanine green–near-infrared fluorescence imaging was performed after injecting 0.5 mL indocyanine green (1.25 mg/mL) into the esophageal submucosa in the 4 peritumoral quadrants. The primary endpoint was to determine the location of the sentinel lymph node in esophageal squamous cell carcinoma based on postoperative pathologic reports. ResultsA total of 40 patients, with 20 in each group, were included in the final analysis. In the indocyanine green group, indocyanine green–near-infrared fluorescence imaging was successful in all subjects. Seven cases (cases 2, 3, 9, 11, 17, 18, and 20) in the indocyanine green group exhibited lymph node metastases, all of which were near-infrared positive. The detection rate, positive predictive value, negative predictive value, sensitivity, and specificity were 100% (20 of 20 cases), 8.7% (13/150), 100% (265/265), 100% (13/13), and 65.9% (265/402), respectively. All near-infrared–negative lymph nodes were nonmetastatic lymph nodes. In addition, the number of mediastinal lymph nodes resected in the indocyanine green group was significantly higher than in the non–indocyanine green group. ConclusionIndocyanine green–near-infrared might be an important and promising technique in predicting sentinel lymph nodes of esophageal squamous cell carcinoma and could significantly improve the detection rate of lymph nodes of esophageal squamous cell carcinoma.

Advantages of contrast-enhanced ultrasound in the localization and diagnostics of sentinel lymph nodes in breast cancer.

Sentinel lymph nodes (SLNs) are the first station of lymph nodes that extend from the breast tumor to the axillary lymphatic drainage. The pathological status of these LNs can predict that of the entire axillary lymph node. Therefore, the accurate identification of SLNs is necessary for sentinel lymph node biopsy (SLNB) to replace axillary lymph node dissection (ALND). The quality of life and prognosis of breast cancer patients are related to proper surgical treatment after the precise identification of SLNs. Some of the SLN tracers that have been identified include radioisotope, nano-carbon, indocyanine green (ICG), and methylene blue (MB). However, these tracers have certain limitations, such as pigmentation, radiation dangers, and the requirement for costly detection equipment. Ultrasound contrast agents (UCAs) have good specificity and sensitivity, and thus can compensate for some shortcomings of the mentioned tracers. This technique is also being applied to SLNB in patients with breast cancer, and can even provide an initial judgment on SLN status. Contrast-enhanced ultrasound (CEUS) has the advantages of high distinguishability, simple operation, no radiation harm, low cost, and accurate localization; therefore, it is expected to replace the traditional biopsy methods. In addition, it can significantly enhance the accuracy of SLN localization and shorten the operation time.

Laparoscopic Sentinel Lymph Node Mapping Using NIR Fluorescence with ICG in Early Endometrial Cancer: Experience at a Tertiary Care Oncology Centre

Objective: To determine the detection rates and location of sentinel nodes as well as to determine intraoperative and postoperative surgico-pathological outcomes in endometrial cancer patients who underwent laparoscopic staging with sentinel node biopsy using ICG dye. Materials and Methods: This retrospective study was conducted in a tertiary care oncology centre, Amrita Institute of medical sciences, Kochi from April 2021 to March 2023. All cases of biopsy proven early stage endometrial carcinoma that underwent laparoscopic staging with SLN mapping using the ICG dye were included. All histological types were included, as long as the disease was confined to the uterus, clinically and on MRI. Results: A total of 80 patients were found eligible for the study. Only the patients with apparent uterine confined disease on preoperative MRI were selected for sentinel mapping, 80 % of whom had IA disease on MRI, and 20 % had IB, 13.5 % were high grade histology.The overall SLN detection rate was 93.75%, and bilateral detection rate was 92.5 %. Most common location was external iliac in 40.8% cases. Only 1 patient was found to harbour nodal micro metastasis on ultrastaging. Final histopathology identified stage IA in 63 (78.75%) patients, IB in 14 (17.5%), Stage II in 2 (2.5%) and Stage IIIC1 in 1 (1.25%) patient. Conclusion: Laparoscopic staging with SLNB using ICG is a practicable approach for uterine limited disease on preoperative evaluation. It extends the benefits of minimally invasive surgery to these patients, while overcoming the limitations of prohibitive cost or availability of expensive robotic equipment.

Variability of Sentinel Lymph Node Location in Patients with Trunk Melanoma.

(1) Background: Melanoma is one of the most aggressive types of neoplasia, and the management of this pathology requires a correct staging, as well as a personalized modern oncological treatment. The main objective of the study is to determine the variability of the lymphatic drainage for patients with melanomas located on the trunk and, secondarily, to determine the features of individuals who underwent sentinel lymph node biopsy (SLNB) depending on the exact location on the trunk. (2) Methods: This retrospective, observational, single-center study included 62 cases of trunk melanoma operated between July 2019 and March 2023, in which SLNB was performed and a total of 84 lymph nodes were excised. (3) Results: Patients had a median age of 54.5 (33-78) years, with 58.1% being male; the melanomas had a median Breslow index of 2.3 (0.5-12.5) mm. Approximately 64.3% of the cohort had melanoma on the upper part of the trunk (54 cases) and 35.7% had it on the lower part (30 cases). The type of anesthesia chosen was general anesthesia in 53 cases and spinal anesthesia in 9 cases (85.5% vs. 14.5%, p < 0.001). The number of sentinel lymph nodes excised was 54 for melanomas located on the upper part of the trunk (8 cervical and 46 axillary) and 30 sentinel lymph nodes for melanomas of the lower part of the trunk (16 at the axillary level and 14 at the inguinal level). Out of the 54 LNs identified in patients with melanoma on the upper part of the trunk, 13 were positive, with a total of 12 positive lymph nodes (LNs) from the axillar basin, and only one from the cervical region. Additionally, the incidence of patients with a minimum of two identified sentinel lymph nodes was 32.2%, with a total of seven having LN involvement in two basins, and only one of these cases showed positivity for malignancy. (4) Conclusions: SLNBs were more frequent in the axillary region overall, and had more positive SLNs. Moreover, melanoma on the upper part of the trunk had a higher rate of positive SLNs compared to the lower part. Tumors located on the lower part of the truck had more positive SLNs in the axillary region than in the inguinal one.

A nanoparticle composed of totally hospital-available drugs and isotope for fluorescence/SPECT dual-modal imaging-guided photothermal therapy to inhibit tumor metastasis

As primary sites of tumor metastasis, sentinel lymph nodes (SLNs) require a highly biocompatible theranostic platform for precise localization and treatment to inhibit tumor metastasis. Herein, indocyanine green-human serum albumin (ICG-HSA) nanoparticles (NPs) were fabricated by ICG-induced self-assembly and radiolabeled with technetuim-99 m (99mTc). The fabricated NPs were composed of hospital-available drugs and isotopes, making them highly biocompatible for in vivo applications. In a mouse model of SLN metastasis, the prepared NPs exhibited excellent capacity for preoperative planning by single-photon emission computed tomography (SPECT) imaging-enabled SLN localization, near-infrared fluorescence (NIRF) imaging-enabled intraoperative real-time monitoring, and SLN photothermal treatment. Photothermal treatment with SLN enhanced the inhibition of lung metastasis and significantly increased the survival time of mice. The prepared NPs were highly biocompatible and exhibited efficient theranostic properties for inhibiting cancer metastasis, making them promising candidates for clinical translation.

The potential of the Crystal Cam handheld gamma-camera for preoperative and intraoperative sentinel lymph node localization in early-stage oral cancer

PurposeEvaluating the Crystal Cam handheld gamma-camera for preoperative and intraoperative sentinel lymph node (SLN) localization in early-stage oral cancer.MethodsThe handheld gamma-camera was used complementary to conventional gamma-probe guidance for intraoperative SLN localization in 53 early-stage oral cancer patients undergoing SLN biopsy. In 36 of these patients, a blinded comparison was made between preoperative handheld gamma-camera and lymphoscintigraphy outcomes. Of those, the reliability for marking the SLN’s location using both handheld gamma-camera and a 57Co-penpoint marker was evaluated in 15 patients.ResultsIn the entire cohort, the handheld gamma-camera preoperatively detected 116/122 (95%) of SLNs identified by lymphoscintigraphy. In those patients where the observer was blinded for lymphoscintigraphy (n = 36), 71/77 (92%) SLNs were correctly identified by handheld gamma-camera. Overlooked SLNs by handheld gamma-camera were mainly located near the injection site. The SLN’s marked location by handheld gamma-camera and 57Co-penpoint marker was considered accurate in 42/43 (98%) SLNs. The intraoperative use of the handheld gamma-camera led to the extirpation of 16 additional ‘hot’ lymph nodes in 14 patients, 4 of which harbored metastases, and prevented 2 patients (4%) from being erroneously staged negative for nodal metastasis. In those with follow-up ≥ 24 months or false-negative outcomes < 24 months following SLNB, a sensitivity of 82% and negative predictive value of 93% was obtained.ConclusionThe Crystal Cam handheld gamma-camera offers reliable preoperative and intraoperative SLN localization and might reduce the risk of missing a malignant SLN during surgery. Detecting SLNs near the injection site by handheld gamma-camera remains challenging.

Real-time Fluorescent ICG and 99m-Tc Nanocolloid Tracer Navigation in Bilateral Sentinel Lymph Node Mapping of Vulvar Cancer

The effectiveness of sentinel lymph node (SLN) biopsy has been validated by two prospective trials, GROINS VI and GOG 1731-2. According to ESGO guideline in patients with unifocal tumors with a diameter of <4 cm, in the absence of suspected inguinal lymph nodes, SLN biopsy is recommended. The use of a radioactive tracer is mandatory.2 Using Indocyanine green (ICG) increase the detection of the vulvar sentinel node from 89.7 to 100%3. Aim of this video is to share our experience about the feasibility, safety and usefulness of the surgical identification of SLN in vulvar cancer using real-time fluorescent indocyanine green with 99m-technetium nanocolloid. Stepwise demonstration of the technique with narrated video footage. Tertiary level hospital "IRCCS Istituto Nazionale dei Tumori", Milano, Italy. A 50-year-old woman was diagnosed with vulvar cancer on biopsy of 1.5 cm size vulvar lesion under the clitoris area and referred to our Operative Unit. F-18 fluorodeoxyglucose positron-emission tomography-computed tomography (PET) showed no extra-vulvar disease. The patient was scheduled for radical vulvectomy and bilateral inguinal sentinel lymph-node biopsy (SLN). In this video the surgical procedure involved double location of SLN, first with the 99m-technetium detector followed by ICG identification. We used an ICG dilution of 2.5 mg/mL in sterile water and injected 4 mL around the tumor 5-10 min before visualization. First a handheld gamma probe used to identify the location of the SLN(s) with 99m-technetium. The fluorescence imaging was performed by the quest imaging system (FLUOPTICS©, Middenmeer, The Netherlands) that combine autofluorescence and fluorescence perfusion imaging. Second, we carried out the SLN biopsy using a dark mood procedure to identify the IGC tracer. The fluorescence imaging enables the detection of these markers through some millimeters of tissue and ICG has the advantage that is visible through the skin4. This video shows a successful combined 99m-technetium and ICG fluorescence image-guided bilateral SLN biopsy in a vulvar cancer patient using a near-infrared (NIR) optical imaging system (FLUOPTICS©). ICG for SLN mapping appears to be safe in women with vulvar cancer with a satisfactory detection rate. This may help in retaining surgical radicality while minimizing operative complications.

Evaluation of sentinel lymph node localization in malignant melanoma by preoperative semiconductor gamma camera and planar lymphoscintigraphy.

Performing lymphoscintigraphy in a separate room, frees up the conventional gamma camera, coupled with the desire to directly localize sentinel lymph nodes (SLN) in the operating theatre has led to the development of high-resolution semiconductor-detector based handheld gamma-cameras, CrystalCam. This work consists of phantom and clinical studies. For the first part, a Jaszczak phantom with hollow spheres of various volumes were filled with the 99m Tc and the camera's sensitivity was measured at various distances to assess the possibilities and limitations of the device. The clinical study evaluates the effectiveness of CrystalCam in localizing SLN in 40 consecutive malignant melanoma patients compared to both conventional planar lymphoscintigraphy and hybrid SPECT/CT. SLNs detected by planar lymphoscintigraphy were marked on the patients' skin using a UV-marker. CrystalCam images were acquired in another room by another examiner and the SLNs were marked with a felt pen. The detected nodes by both camera systems were evaluated using UV-lamp and normal light to visualize the UV- and felt pen marks respectively. The concordance rate of the SLNs and higher-echelon nodes localized by both planar scintigraphy and CrystalCam imaging with respect to the total SLNs and higher-echelon nodes detected by SPECT/CT imaging are compared and statistically analyzed. The results of the phantom study show a good correlation between activity and count-rates for all distancesSPECT/CT, CrystalCamm, and planar lymphoscintigraphy detected 69, 58, and 61 SLNs respectively. The concordance rate of 95.65% by the CrystalCam and planar scintigraphy implies both cameras are statistically coequal in preoperative SLN detection of malignant melanoma. For the higher-echelon nodes, SPECT/CT, planar and CrystalCam imaging systems identified 82, 48, and 13 respectively; thus, CrystalCam was statistically inferior to planar imaging. The handheld CrystalCam is a reliable instrument for localizing SLNs in surgical centers without an on-site nuclear medicine department.

Non-Invasive Detection, Precise Localization, and Perioperative Navigation of In Vivo Deep Lesions Using Transmission Raman Spectroscopy.

Non-invasive detection and precise localization of deep lesions have attracted significant attention for both fundamental and clinical studies. Optical modality techniques are promising with high sensitivity and molecular specificity, but are limited by shallow tissue penetration and the failure to accurately determine lesion depth. Herethe authors report in vivo ratiometric surface-enhanced transmission Raman spectroscopy (SETRS) for non-invasive localization and perioperative surgery navigation of deep sentinel lymph nodes in live rats. The SETRS system uses ultrabright surface-enhanced Raman spectroscopy (SERS) nanoparticles with a low detection limit of 10 pM and a home-built photosafe transmission Raman spectroscopysetup. The ratiometric SETRS strategy is proposed based on the ratio of multiple Raman spectral peaks for obtaining lesion depth. Via this strategy, the depth of the phantom lesions in ex vivo rat tissues is precisely determined with a mean-absolute-percentage-error of 11.8%, and the accurate localization of a 6-mm-deep rat popliteal lymph node is achieved. The feasibility of ratiometric SETRS allows the successful perioperative navigation of in vivo lymph node biopsy surgery in live rats under clinically safe laser irradiance. This study represents a significant step toward the clinical translation of TRS techniques, providing new insights for the design and implementation of in vivo SERS applications.

The Evaluation of Sentinel Lymph Node Biopsy Using Radiocolloid in First Stage Endometrial Cancer.

Detection of a sentinel lymph node (SLN) in patients with endometrial cancer (EC) reduces the rate of unnecessary systemic lymph dissection. The aim of this study was to assess the SLN detection rate, accuracy of the method using Tc-99m-SENTI-SCINT and the rate of metastatic nodal involvement in patients with preoperative first stage EC. A prospective study of SLN biopsy of 41 patients with stage I EC was conducted after cervical application of 4mCi Tc-99m-SENTI-SCINT. Planar lymphoscintigraphy and single-photon emission computed tomography/computed tomography (SPECT/CT) of the pelvis were performed, followed by site-specific lymphadenectomy in intermediate-risk patients if no SLN was detected per hemipelvis and pelvic lymphadenectomy in all high-risk patients. Pre-operative detection rate of planar lymphoscintigraphy was 80.49 [95% confidence interval (CI): 68.36-92.62] and of SPECT/CT 95.12 (95% CI: 88.52-101.7). The total intraoperative SLN detection rate was 95.12 (95% CI: 88.52-101.7) per patient and 26.83 (95% CI: 19.91-33.75) bilaterally. The average number of SLNs removed was 1.6±0.8. The most common anatomical location of SLN was the right external iliac region. The SLN metastatic rate was 17%. Both sensitivity and negative predictive value regarding metastatic involvement were 100%. The SLN detection rate, sensitivity and negative predictive value using Tc-99m-SENTI-SCINT in patients with EC in our study were high. The application of ultra-staging in the histopathological analysis of SLN increases the detection of nodal metastases and improves the staging in these patients.