Planar Lymphoscintigraphy Research Articles

Detection of Chyle Leakage Site With Lymphoscintigraphy SPECT/CT in a Patient With Chylothorax Secondary to T-Cell Lymphoblastic Leukemia.

We present a pediatric case with T-cell lymphoblastic leukemia and persistent chylothorax who was referred to lymphoscintigraphy to identify the site of leakage. Planar lymphoscintigraphy with SPECT/CT revealed hot spots at the left jugulovenous angle and the confluens of the vena brachiocephalica to vena cava, which were compatible with the sites of leakage. Hybrid imaging with SPECT/CT technique have great impact on accurate detection of the defects in the lymphatic system in patients with chylothorax.

Comparison of 99mTc-Labeled Colloid SPECT/CT and Planar Lymphoscintigraphy in Sentinel Lymph Node Detection in Patients with Melanoma: A Meta-Analysis.

We compared the detection rate (DR) for sentinel lymph nodes (SLNS), the number of SLNs and the subjects with additional SLNs of single-photon emission computed tomography (SPECT/CT) and planar lymphoscintigraphy (PL) in patients with melanoma. Furthermore, we evaluated the impact of SPECT/CT on surgical plans. Articles containing head-to-head comparisons between SPECT/CT and PL were searched in Pubmed/MEDLINE and Scopus. The literature search was updated until December 31st, 2019. DR was calculated on a per-patient-based analysis; the studies were pooled by their odds ratios (ORs) with a random effects model to assess the significance of difference (p < 0.05). The number of additional SLNs (calculated as the relative risk) and pooled proportion of patients with additional SLNs were investigated. The pooled ratio of surgical procedures influenced by the SPECT/CT findings was calculated. Seventeen studies with 1438 patients were eligible for the calculation of DR of SPECT/CT and PL. The average DR was 98.28% (95% confidence interval (95% CI): 97.94–99.19%) for the SPECT/CT and 95.53% (95% CI: 92.55–97.77%) for the PL; OR of 2.31 (95% CI: 1.66–4.18, p < 0.001) in favor of the SPECT/CT. There was a relative risk of a higher number of SLNs (1.13) for the SPECT/CT and 17.87% of patients with additional SLNs were detected by SPECT/CT. The average impact of SPECT/CT on surgery resulted in 37.43% of cases. This meta-analysis favored SPECT/CT over PL for the identification of SLNs in patients with melanoma due to a higher DR, reproducibility, number of SLNs depicted, proportion of patients with additional SLNs and the impact on the surgical plan. However, PL remains a good option due to the high values of the DR for SLNs.

Sentinel Node Identification in Melanoma: Current Clinical Impact, New Emerging SPECT Radiotracers and Technological Advancements. An Update of the Last Decade.

Background: Melanoma is the most lethal skin cancer with a mortality rate of 262 cases per 100.000 cases. The sentinel lymph node (SLN) is the first lymph node draining the tumor. SLN biopsy is a widely accepted procedure in the clinical setting since it provides important prognostic information, which helps patient management, and avoids the side effects of complete lymph node dissection. The rationale of identifying and removing the SLN relies on the low probability of subsequent metastatic nodes in case of a negative histological exam performed in the SLN.Discussion: Recently, new analytical approaches, based on the evaluation of scintigraphic images are also exploring the possibility to predict the metastatic involvement of the SLN. 99mTc-labeled colloids are still the most commonly used radiotracers but new promising radiotracers, such as 99mTc-Tilmanocept, are now on the market. In the last decades, single photon emission computed tomography-computerized tomography (SPECT/CT) has gained wider diffusion in clinical departments and there is large evidence about its superior diagnostic accuracy over planar lymphoscintigraphy (PL) in the detection of SLN in patients with melanoma. Scientists are also investigating new hybrid techniques combining functional and anatomical images for the depiction of SLN but further evidence about their value is needed.Conclusion: This review examined the predictive and prognostic factors of lymphoscintigraphy for metastatic involvement of SLN, the currently available and emerging radiotracers and the evidence of the additional value of SPECT/CT over PL for the identification of SLN in patients with melanoma. Finally, the review discussed the most recent technical advances in the field.

Sentinel lymph node biopsy in oral–oropharyngeal squamous cell carcinoma: standards, new technical procedures, and clinical advances

To provide substantial coverage and critical appraisal of standards as well as new technical procedures and clinical advances concerning sentinel lymph node biopsy (SNB) in oral squamous cell carcinoma (OSCC). The MEDLINE database was searched via the PubMed interface up to January 2019 for the following MeSH heading: “sentinel lymph node biopsy” and “squamous cell carcinoma of head and neck”. SNB exists as an alternative to elective neck dissection (END) in OSCC. Pre-surgical planar lymphoscintigraphy with intra-operative hand-held gamma probe allows using SNB. Furthermore, the contribution of pre-surgical SPECT/CT improves the sentinel lymph node (SLN) roadmap in sites that are closer to the injection site. Portable gamma camera and freehand SPECT are not yet routine clinical practice, but can further improve intra-operative SLN detection. However, the difficulty in detecting SLNs located closer to the injection site persists. SNB with combined radioactive and near-infrared fluorescence guidance is an attractive option for improving spatial resolution of radio-guided techniques while maintaining depth penetration. Numerous studies have demonstrated that SNB can be proposed for accurate histopathological staging of the neck and the guidelines support the introduction of SNB as an alternative to END in T1/T2 N0 OSCC patients. New hybrid imaging techniques, which are offering new possibilities to assist clinicians and surgeons in localizing the site of uptake in sentinel node detection, need to be confirmed in ongoing and future clinical trials. In the future, the integration of new PET tracers could continue along the route mapped out in SNB.

Predictive risk factors for sentinel lymph node nonvisualization on planar lymphoscintigraphy using an intratumoral injection in patients with primary breast cancer.

Lymphoscintigraphy is considered a useful tool to optimize sentinel lymph node (SLN) identification. Nonvisualization of the SLN is associated with a lower SLN identification rate. The aim of this study was to identify preoperative factors associated with SLN nonvisualization on lymphoscintigraphy. A total of 2050 consecutive SLN procedures were evaluated from clinically node-negative breast cancer patients. Planar lymphoscintigraphy was performed at 3 h after an intratumoral injection of technetium-99m-nanocolloid. This technique was used for extra-axillary SLN identification. Patient, tumor, and treatment characteristics were analyzed for association with SLN nonvisualization. Factors with a P-value less than 0.1 in univariate analysis were included in a multivariate logistic regression model. The SLN visualization rate was 86.7%. In multivariate logistic regression, age of at least 70 years [odds ratio (OR): 3.24; 95% confidence interval (CI): 2.14-4.91)], BMI of at least 30 (OR: 1.93; 95% CI: 1.39-2.69), T3/T4-tumors (OR: 2.70; 95% CI: 1.37-5.32), medially/centrally located tumors (OR: 1.52; 95% CI: 1.17-1.99), previous mantle field radiation (OR: 4.04; 95% CI: 1.74-9.35), nonpalpable tumors (OR: 1.88; 95% CI: 1.36-2.60), and presence of iodine seeds (OR: 1.35; 95% CI: 1.02-1.78) were associated significantly with nonvisualization on lymphoscintigraphy. Nonvisualization was the strongest independent predictor of unsuccessful intraoperative SLN identification (P<0.001). Overall, the SLN identification rate was 97.7% because of the use of additional imaging and blue dye. This study reports new tumor and treatment-related risk factors for nonvisualization on lymphoscintigraphy by using an intratumoral injection in primary breast cancer. We recommend a periareolar subcutaneous injection to improve SLN visualization in patients with limited prognostic and therapeutic relevance of internal mammary chain SLN identification.

Clinical Value of Single-photon Emission Computed Tomography Combined With Computed Tomography for Sentinel Lymph Node Identification in Melanoma.

Melanoma is the deadliest form of skin cancer and has the ability to metastasize widely. Accurate diagnosis of sentinel lymph nodes (SLN) is crucial to its management. The gold standard for SLN identification is planar lymphoscintigraphy. Recently, single-photon emission computed tomography combined with computed tomography (SPECT/CT) has been used as a hybrid method to map lymphatic drainage networks. We aim to better characterize the utility of this tool in head and neck melanoma by evaluating its effectiveness in the preoperative setting for melanoma patients undergoing sentinel lymph node biopsy (SLNB). We performed a retrospective chart review at the West Haven Veterans Affairs Hospital. Inclusion criteria were patients with melanoma with a thickness greater than 0.75 mm and SPECT/CT use before operative sentinel lymph node excision. Exclusion criteria included clinically palpable lymph nodes, evidence of distant metastatic disease, melanoma with a Breslow depth less than 0.75 mm, and melanoma in situ. Our primary endpoints were correlation with intraoperative findings and whether the test had any influence on the operative plan. Thirty-five patients between 2011 and 2017 met our criteria. SPECT/CT correlated with the sentinel node biopsy based on intraoperative lymphoscintigraphy in 30 (86%) of 35 cases, and there were no changes to the operative plan after SPECT/CT was performed. Sentinel lymph nodes were correctly identified in all 35 cases. The role of SPECT/CT in SLNB is uncertain. According to some studies, SPECT/CT can help decision making and change surgical approach in up to 35% of patients. However, other studies have reported questionable correlation with intraoperative findings and no added intraoperative value in over 50% of patients. We have demonstrated that preoperative SPECT/CT was consistent with intraoperative findings in 86.0% of cases but did not change the surgical approach for the SLNB. Surveillance over a period of 12 months did not reveal any signs of melanoma recurrence. A possible advantage of SPECT/CT is potentially decreasing costs by lowering operative time. However, financial cost in the literature suggests SPECT/CT is costlier than lymphoscintigraphy and therefore this must be weighed against any potential benefit. Overall, we did not find that SPECT/CT gives added value when compared with lymphoscintigraphy.

Sentinel Lymph Node Biopsy in Small Papillary Thyroid Cancer: A Meta-analysis.

The aim of this study was to compare reported results on available techniques for sentinel lymph node detection rate (SDR) in papillary thyroid cancer (PTC). The MEDLINE database was searched via a PubMed interface to identify original articles regarding sentinel lymph node biopsy (SNB) in thyroid cancer. Studies were stratified according to the sentinel lymph node (SLN) detection technique: vital-dye (VD), Tc-nanocolloid planar lymphoscintigraphy with the use of intraoperative hand-held gamma probes (LS), both Tc-nanocolloid planar lymphoscintigraphy with intraoperative use of hand-held gamma probe and VD (LS + VD), Tc-nanocolloid planar lymphoscintigraphy with the additional contribution of preoperative SPECT/CT, and intraoperative use of hand-held gamma probe (LS-SPECT/CT). Pooled SDR values were presented with a 95% confidence interval (CI) for each SLN detection techniques. A Z-test was used to compare pooled SDR estimates. False-negative rates were summarized for each method. Forty-five studies were included. Overall SDRs for the VD, LS, LS + VD, and LS-SPECT/CT techniques were 83% (95% CI, 77%-88%; I = 78%), 96% (95% CI, 90%-98%; I = 68%), 87% (95% CI, 65%-96%; I = 75%), and 93% (95% CI, 86%-97%; I = 0%), respectively. False-negative rates were 0% to 38%, 0% to 40%, 0% to 17%, and 7% to 8%, respectively. In patients with PTC, Tc-nanocolloids offer a higher SDR than that of the VD technique. The addition of SPECT/CT improved identification of metastatic SLNs outside the central neck compartment.

Selective biopsy of the sentinel node in cancer of cervix: Experience in validation phase.

Sentinel lymph node biopsy (SLNB) was created to reduce the morbidity associated with pelvic lymphadenectomy in the early stages of cervical cancer (CC), preserving its prognostic information. The goal is to assess the diagnostic validity of SLNB in CC in initial stages (IA1 with lymphovascular infiltration (LVI) +, IA2, IB1 and IIA1), thus avoiding unnecessary lymphadenectomies in many of the cases. From January 2012 to April 2017, 23 patients with initial stages of CC were included in a cross-sectional study to evaluate the effectiveness of the SLNB in CC with a mixed technique of cervical injection of 99mTc-nanocolloid of albumin and methylene blue, using combined planar lymphoscintigraphy with multimodality SPECT/CT image and subsequent removal of the sentinel node (SN) by laparoscopy. The detection rate of SLNB with the mixed technique was 95.65%, with a negative predictive value (NPV) of 95.45% and sensitivity (S) of 100% in the case of bilateral drainage. The mean of excised SN was 3 (range 1-5). The bilateral detection rate in laparoscopy was 85.35%. The concordance between SPECT/CT and laparoscopy for the number and bilaterality of the SN using the Pearson coefficient was r = 0.727 and r = 0.833, respectively; p = 0.01. We only found one SN with a deferred result of micrometástasis and one false negative was detected. SLNB in CC using a mixed technique has a high detection and bilateral drainage rate, but S is still low if we include cases of unilateral drainage. A greater number of cases and the development of intraoperative ultrastaging could increase the S of the technique and to reduce the number of false negatives.

Selective biopsy of the sentinel node in cancer of cervix: Experience in validation phase

Background and objectiveSentinel lymph node biopsy (SLNB) was created to reduce the morbidity associated with pelvic lymphadenectomy in the early stages of cervical cancer (CC), preserving its prognostic information. The goal is to assess the diagnostic validity of SLNB in CC in initial stages (IA1 with lymphovascular infiltration (LVI)+, IA2, IB1 and IIA1), thus avoiding unnecessary lymphadenectomies in many of the cases. Material and methodFrom January 2012 to April 2017, 23 patients with initial stages of CC were included in a cross-sectional study to evaluate the effectiveness of the SLNB in CC with a mixed technique of cervical injection of 99mTc-nanocolloid of albumin and methylene blue, using combined planar lymphoscintigraphy with multimodality SPECT/CT image and subsequent removal of the sentinel node (SN) by laparoscopy. ResultsThe detection rate of SLNB with the mixed technique was 95.65%, with a negative predictive value (NPV) of 95.45% and sensitivity (S) of 100% in the case of bilateral drainage. The mean of excised SN was 3 (range 1–5). The bilateral detection rate in laparoscopy was 85.35%. The concordance between SPECT/CT and laparoscopy for the number and bilaterality of the SN using the Pearson coefficient was r=0.727 and r=0.833, respectively; p=0.01. We only found one SN with a deferred result of micrometastasis and one false negative was detected. ConclusionsSLNB in CC using a mixed technique has a high detection and bilateral drainage rate, but S is still low if we include cases of unilateral drainage. A greater number of cases and the development of intraoperative ultrastaging could increase the S of the technique and to reduce the number of false negatives.

Zonal mapping of sentinel lymph nodes in penile cancer patients using fused SPECT/CT imaging and lymphoscintigraphy

PurposeTo define the anatomical location of sentinel lymph nodes (SLN) in penile cancer patients based on Daseler's original zonal description using a combination of single photon emission computed tomography-computed tomography (SPECT-CT), cross sectional imaging and lymphoscintigraphy and characterise the limits of Zone V. Materials and methodsPatients with primary penile cancer ≥T1G2 were included in the study. A total of 113 groins with impalpable inguinal lymph nodes (cN0) underwent planar lymphoscintigraphy and SPECT-CT. The sentinel lymph nodes were mapped on cross sectional imaging according to Daseler's anatomical description. Using measurements from fixed anatomical landmarks, a custom-made software program mapped the SLNs. SLNs were mapped to the previously undefined Zone V using 3 approaches to avoid observational bias: (a) as perceived by the uroradiologist, (b) limiting Zone V to a 5 mm radius from the sapheno-femoral junction or (c) using a 10 mm radius from the sapheno-femoral junction. ResultsUsing SPECT-CT, drainage to the groins was seen in 109 of the 113 cN0 groins (96.5%). The majority of the SLNs were located in the central and superior quadrants with 38.2% lying within Zone I, 45% in Zone II and 13% in Zone V. More importantly, sentinel lymph nodes were still localised to the inferior zones with 3% located in Zone III and 0.8% in Zone IV. ConclusionsUsing a hybrid of SPECT-CT, cross sectional imaging and lymphoscintigraphy we have demonstrated that SLNs may be located in the inferior zones. We also define the limits of Zone V as an area of 5 mm radius from the sapheno-femoral junction.

SPECT/CT Adds Distinct Lymph Node Basins and Influences Radiologic Findings and Surgical Approach for Sentinel Lymph Node Biopsy in Head and Neck Melanoma

Planar lymphoscintigraphy (PL) has a lower detection rate of sentinel lymph nodes (SLNs) in head and neck melanoma compared with other sites. We assessed situations when single-photon emission computed tomography/computed tomography (SPECT/CT) identified nodes not seen by PL. We also evaluated the impact of SPECT/CT on surgical approach and oncologic outcomes. Patients who underwent SLN biopsy (SLNB) for head and neck melanoma with PL and SPECT/CT between November 2011 and December 2016 were included. Surgeons and radiologists completed a real-time survey inquiring about the utility of SPECT/CT. Patients were divided into two groups: patients with nodal basins identified by both PL and SPECT/CT ('PL+SPECT/CT'), and patients in whom SPECT/CT identified additional nodal basins not seen on PL ('SPECT/CT only'). Patient demographics and long-term outcomes including follow-up duration, recurrence, and survival are described. In the PL+SPECT/CT group, 73 (61.9%) patients were included and 45 (38.1%) patients were included in the SPECT/CT-only group. SPECT/CT added 51 basins to those seen on PL, primarily in the supraclavicular region (43.1%). Eighteen patients had positive node(s) in the PL+SPECT/CT group compared with two patients in the SPECT/CT-only group. Surgeons reported that 81% of the time, SPECT/CT influenced the location of incision for SLNB. SPECT/CT influences the location of incision and contributes most to identification of nodes in the supraclavicular region. It also detects additional SLN basins when compared with PL. Further studies are necessary to determine when these additional basins require sampling.

Investigating the role of SPECT/CT in dynamic sentinel lymph node biopsy for penile cancers

PurposeCurrently, most centres use 2-D planar lymphoscintigraphy when performing dynamic sentinel lymph node biopsy in penile cancer patients with clinically impalpable inguinal nodes. This study aimed to investigate the role of SPECT/CT following 2-D planar lymphoscintigraphy (dynamic and static) in the detection and localization of sentinel lymph nodes in the groin.MethodsA qualitative (visual) review was performed on planar followed by SPECT/CT lymphoscintigraphy in 115 consecutive patients (age 28–86 years) who underwent injection of 99mTc-nanocolloid followed by immediate acquisition of dynamic (20 min) and early static scans (5 min) initially and further delayed static (5 min) images at 120 min followed by SPECT/CT imaging. The lymph nodes detected in each groin on planar lymphoscintigraphy and SPECT/CT were compared.ResultsA total of 440 and 467 nodes were identified on planar scintigraphy and SPECT/CT, respectively. Overall, SPECT/CT confirmed the findings of planar imaging in 28/115 cases (24%). In the remaining 87 cases (76%), gross discrepancies were observed between planar and SPECT/CT images. SPECT/CT identified 17 instances of skin contamination (16 patients, 13%) and 36 instances of in-transit lymphatic tract activity (24 patients, 20%) that had been interpreted as tracer-avid lymph nodes on planar imaging. In addition, SPECT/CT identified 53 tracer-avid nodes in 48 patients (42%) that were not visualized on planar imaging and led to reclassification of the drainage basins (pelvic/inguinal) of 27 tracer-avid nodes.ConclusionsThe addition of SPECT/CT improved the rate of detection of true tracer-avid lymph nodes and delineated their precise (3-D) anatomic localization in drainage basins.

The added value of SPECT-CT for the identification of sentinel lymph nodes in early stage oral cancer

PurposeTo assess the role of single-photon emission computed tomography with computed tomography (SPECT-CT) for the identification of sentinel lymph nodes (SLNs) in patients with early stage (T1–T2) oral cancer and a clinically negative neck (cN0).MethodsIn addition to planar lymphoscintigraphy, SPECT-CT was performed in 66 consecutive patients with early stage oral cancer and a clinically negative neck. The addition of SPECT-CT to planar images was retrospectively analyzed for the number of additional SLNs, more precise localization of SLNs, and importance of anatomical information by a team consisting of a nuclear physician, surgeon, and investigator.ResultsIdentification rate for both imaging modalities combined was 98% (65/66). SPECT-CT identified 15 additional SLNs in 14 patients (22%). In 2/15 (13%) of these additional SLNs, the only metastasis was found, resulting in an upstaging rate of 3% (2/65). In 20% of the patients with at least one positive SLN, the only positive SLN was detected due to the addition of SPECT-CT. SPECT-CT was considered to add important anatomical information in two patients (3%). In 5/65 (8%) of the patients initially scored SLNs on planar lymphoscintigrams were scored as non-SLNs when SPECT-CT was added. There were four false-negative SLN biopsy procedures in this cohort.ConclusionsThe addition of SPECT-CT to planar lymphoscintigraphy is recommended for the identification of more (positive) SLNs and better topographical orientation for surgery in sentinel lymph node biopsy for early stage oral cancer.

Comparison of SPECT/CT and Planar Lympho-scintigraphy in Sentinel Node Biopsies of Oral Cavity Squamous Cell Carcinomas.

Introduction:Evidence supporting the use of Sentinel node biopsy (SNB) for nodal staging of early oral squamous cell carcinomas (OSCC) appears to be very promising. Pre-operative lymphatic mapping using planar lymphoscinitigraphy (PL) with or without SPECT/CT in the SNB procedure is useful in sentinel node localization and for planning appropriate surgery. Recently, a large prospective multi-centric study evaluating SNB in cutaneous melanoma, breast and pelvic malignancies, demonstrated that adding SPECT to PL leads to surgical adjustments in a considerable number of patients. Our aim of this study was to evaluate the incremental value of additional SPECT/CT over PL alone in SNB for OSCC.Materials and Methods:This was a retrospective analysis of 44 patients (40- tongue, 4- buccal mucosa) with T1-T2, clinically N0 oral cavity SCC who underwent sentinel node biopsy procedure. PL and SPECT lymphoscinitigraphy images were compared for pre-operative mapping of sentinel nodes.Results:Using a handheld gamma probe, a total of 179 sentinel nodes were harvested, with a mean of 4.06 per patient. PL revealed 75 hotspots with a mean of 1.70 per patient, and SPECT/CT revealed 92 hotspots with a mean of 2.09 per patient. Additional hotpots were identified in 14 patients on SPECT/CT, which included 4 patients, where PL did not detect any sentinel nodes.Conclusion:Pre-operative SPECT/CT in addition to planar lympho-scinitigraphy in sentinel node biopsies of oral cavity SCC detects more number of sentinel nodes compared to planar imaging alone. The higher sensitivity of SPECT combined with better anatomical localization using diagnostic CT may further improve the precision of SNB procedure.

Application of sentinel lymph node dissection in gynecological cancers: results of a survey among German hospitals.

Evaluating the application of the sentinel lymph node dissection (SLND) in gynecological cancers among German hospitals. Between March and June 2016 an online questionnaire on SLND in gynecologic cancers was sent by email to all German gynecologic cancer centers, all university hospitals and general hospitals for which an email address was available. The survey contained 61 questions regarding the SLND in vulvar, cervical, endometrial and ovarian cancer. In total, 63 clinics, including 13 (20.6%) university hospitals, 28 (44.4%) hospitals offering maximum care and 22 (34.9%) general hospitals, responded to the questionnaire. Most clinics (46/63, 73%) performed SLND in vulvar cancer with a median amount of 7.8 (range 1-43) SLND per year. 56.5% of the clinics included patients according to the German national guidelines and performed ultrastaging of negative SLN. Furthermore, 18/63 (28.5%) of the responding clinics applied SLND in cervical cancer including 7 (77.8%) centers which conducted isolated SLND without radical pelvic lymph node dissection (LND). Preoperative imaging with planar lymphoscintigraphy (LSG) was applied in 12/18 (66.7%) of the clinics. SLND in endometrial cancer was reported by 4/63 (6.4%) hospitals. Three of them (75%) regularly performed a subsequent radical pelvic LND. One clinic (1.5%) reported SLND in ovarian cancer in combination with radical LND. Especially in vulvar and cervical cancer, isolated SLND appears to be partially implemented in the routine surgical treatment. However, this survey illustrates a wide heterogeneity regarding inclusion criteria and application of the SLND approach.

Comparison of (99)Tcm -rituximab planar and SPECT / CT lymphoscintigraphy for sentinel lymph nodes of breast cancer

Objective To investigate the advantages of SPECT/CT in preoperative SLN localization of primary breast cancer by comparing with planar lymphoscintigraphy in the same patient. Methods From May 2015 to December 2015, 104 female patients (age range: 33-82 years, average age(59.71±12.33)years) with stageⅠ-Ⅱbreast cancer had preoperative peritumoral injection of 18.5 MBq (0.5 ml) of 99Tcm-rituximab under the guidance of ultrasound. Planar and SPECT/CT lymphoscintigraphy were acquired at 2-4 h post injection since SLN detection was difficult on skin of axilla by a handheld portable detector at 2 h after injection. Axillary SLNs were detected by a handheld portable detector and examined pathologically with both HE and immunohistochemical staining. χ2 test and paired t test were used for data analysis. Results The success rate of planar imaging and SPECT/CT was 88.46%(92/104) and 98.08%(102/104), respectively, with statistically significant difference (χ2=7.658, P<0.05). Negative imaging was more common in older patients, or those with history of neoadjuvant chemotherapy or metastatic SLNs. The numbers of SLNs detected by the 2 imaging methods were 122 vs 166 or (1.17±0.73)/patient vs (1.60±0.95)/patient (t=2.533, P<0.01). SLNs were found in axilla, internal mammary and interpectoral stations. The patients received an additional (3.41±0.59) mSv effective dose in SPECT/CT compared with planar imaging. A total of 174 axillary fossa and/or interpectoral SLNs were harvested by a handheld portable gamma detector in 84 cases, and 46 SLNs in 17 patients were pathologically confirmed as metastasis. Conclusion SPECT/CT could detect more SLNs and is more accurate than planar lymphoscintigraphy, suggesting that it is useful in SLN biopsy of breast cancer. Key words: Breast neoplasms; Sentinel lymph node biopsy; Tomography, emission-computed, single-photon; Tomography, X-ray computed; Antibodies, monoclonal

Technetium-99m-labeled rituximab for use as a specific tracer of sentinel lymph node biopsy: a translational research study.

PurposeWe aimed to develop and translate a CD20-antigen-targeted radiopharmaceutical, Technetium-99 m-labeled (99mTc) rituximab, for sentinel lymph node (SLN) detection.Methods99mTc-rituximab was synthesized and tested for stability in human serum. The binding affinity to CD20 was evaluated in Raji cells by flow cytometric analysis. Biodistribution and sentinel node mapping were carried out in bal b/c mice. Eighty-five patients with breast cancer participated in this study. Dynamic sentinel lymphoscintigraphy was first assessed in 12 patients before planar lymphoscintigraphy was assessed in a larger cohort. All patients underwent sentinel lymph node biopsy (SLNB), followed by axillary lymph node dissection.ResultsThe cell-binding study showed that 99mTc-rituximab possessed compatible affinity to human CD20. In the mechanism study, 99mTc-labeled anti-mouse CD20 monoclonal antibodies could bind to mouse CD20 and accumulate in the SLN with 2.62±1.25 % of the percentage of injected activity, which could be blocked by excessive unlabeled antibody. Low uptake of non-sentinel nodes and fast clearance from the injection site were observed in the mice. Sentinel nodes were identified in 82 of 85 breast cancer patients (96.5%) by lymphoscintigraphy and SLNB. The sensitivity, specificity, and accuracy were 96.8% (30/31), 100% (51/51), and 98.8% (81/82), respectively.Conclusion99mTc-rituximab, specifically binding to CD20, met most of the requirements of an ideal sentinel mapping agent for use in clinical settings.

SPECT/CT Improves Detection of Metastatic Sentinel Lymph Nodes in Patients with Head and Neck Melanoma.

A positive sentinel lymph node (SLN) is the most important prognostic factor for predicting survival in cutaneous melanoma. This study aimed to evaluate how the addition of single-photon emission computed tomography (SPECT) and computed tomography (CT) to planar lymphoscintigraphy (PL) alters SLN identification, yield, and localization of metastatic nodes in head and neck melanoma. This retrospective review examined patients undergoing SLN biopsy for cutaneous melanoma of the head and neck between July 2003 and December 2015. Patient demographics and pathologic outcomes were compared for patients undergoing SPECT-CT versus PL. A multivariable logistic regression analysis was used to identify factors associated with the identification of a positive SLN. Among 176 patients undergoing SLN biopsy, 91 underwent PL and 85 underwent SPECT-CT and PL. The patients in the SPECT-CT group were older than the PL patients (p=0.050) but the groups did not differ in gender (p=0.447), Breslow thickness (p=0.744), or total number of SLNs identified (p=0.633). As shown by the multivariate regression analysis, only Breslow thickness [odds ratio (OR) 1.47; 95% confidence interval (CI) 1.17-1.84] and SPECT-CT (OR 3.58; 95% CI 1.24-10.4) were associated with a positive SLN. The use of SPECT-CT for patients with head and neck cutaneous melanoma significantly increases the likelihood of retrieving a positive SLN. Long-term follow-up evaluation is needed for further definition of the impact that SPECT-CT has on recurrence and survival.

Groin Recurrences in Node Negative Vulvar Cancer Patients After Sole Sentinel Lymph Node Dissection.

This study aimed to evaluate the recurrence rates after sole sentinel dissection in vulvar cancer and describe characteristics of groin recurrences. All vulvar cancer cases between 2008 and 2014 were reviewed. Inclusion criteria were restricted to lymph node-negative patients, sole sentinel lymph node dissection (SLND), and tumor diameter less than 4 cm. In all patients, Tc-99m nanocolloid was used for preoperative SLN imaging. Regularly, planar lymphoscintigraphy and single-photon emission computed tomography with computed tomography were performed. Ultrastaging was routinely conducted on all negative lymph nodes. Of 140 vulvar cancer cases, 30 node-negative patients underwent sole SLND and met inclusion criteria. Keratinizing squamous cell carcinoma was determined in final histology in 20/30 (66.7%) patients and the mainly diagnosed tumor stage was pT1b (21/30, 70%). Three perioperative complications occurred. On average, 4.6 (1-9) SLNs were dissected per patient and 2.5 (1-6) per each groin, respectively. During a median follow-up of 43.5 (4-75) months, 5/30 (16.7%; 95% confidence interval, 7.3%-33.6%) local recurrences occurred. In addition, 2/30 (6.6%; 95% confidence interval, 1.9%-21.3%) groin recurrences were identified within a period of 12 months after the primary surgery. Both patients had large (>2 cm) midline tumors. Despite surgical as well as adjuvant treatment of the recurrent disease, both patients with groin recurrences died. Sentinel lymph node dissection is a safe and feasible alternative in early vulvar cancer. But false-negative sentinel carry a high risk of mostly fatal groin recurrences. Especially, midline tumors larger than 2 cm have to be treated with caution, because they are mostly found in cases with groin recurrences after sole SLND.

Role of SPECT-CT in sentinel lymph node biopsy in patients diagnosed with head and neck melanoma

ObjectiveAssess the role of SPECT-CT in sentinel lymph node (SLN) biopsy in the accurate anatomical location of the SNL in patients with cutaneous head and neck melanoma. Material and methodsA retrospective study was conducted from February 2010 to June 2013 on 22 consecutive patients with a diagnosis of cutaneous head and neck melanoma (9 female, 13 male), with a mean age of 55 years old and who met the inclusion criteria for SLN biopsy. Patients underwent preoperative scanning after peri-scar injection of 99mTc-labeled-nanocolloid. Planar images of the injection-site, whole-body, and SPECT-CT scanning were acquired. ResultsDetection rate of SLN reached up to 91% (20/22 patients) by planar lymphoscintigraphy and 95.4% (21/22 patients) by SPECT-CT. SPECT-CT provided an accurate location of SLN in 14/22 patients, enabling to improve the surgical approach (clinical impact: 63.6%). SLN was positive for metastatic cells in 9.1% patients. ConclusionSPECT-CT provides detailed anatomical SLN location and allows detecting a higher number of SLN than planar lymphoscintigraphy. Routine use of SPECT-CT is recommended in order to optimize the SLN detection and location in patients with head and neck melanoma.