Surgical radioguidance with beta-emitting radionuclides; challenges and possibilities: A position paper by the EANM.

Radioguidance that makes use of ß-emitting radionuclides is gaining in popularity and could have potential to strengthen the range of existing radioguidance techniques. While there is a strong tendency to develop new PET radiotracers, due to favorable imaging characteristics and the success of theranostics research, there are practical challenges that need to be overcome when considering use of ß-emitters for surgical radioguidance. In this position paper, the EANM identifies the possibilities and challenges that relate to the successful implementation of ß-emitters in surgical guidance, covering aspects related to instrumentation, radiation protection, and modes of implementation.

Steerable DROP-IN radioguidance during minimal-invasive non-robotic cervical and endometrial sentinel lymph node surgery.

PURPOSE: The recently introduced tethered DROP-IN gamma probe has revolutionized the way robotic radioguided surgery is performed, fully exploiting the nature of steerable robotic instruments. Given this success, the current first-in-human study investigates if the DROP-IN can also provide benefit in combination with steerable non-robotic instruments during conventional laparoscopic surgery, showing equivalence or even benefit over a traditional rigid gamma probe. METHODS: The evaluation was performed in ten patients during laparoscopic cervical (n = 4) and endometrial (n = 6) cancer sentinel lymph node (SLN) procedures. Surgical guidance was provided using the hybrid, or bi-modal, SLN tracer ICG-99mTc-nanocolloid. SLN detection was compared between the traditional rigid laparoscopic gamma probe, the combination of a DROP-IN gamma probe and a steerable laparoscopic instrument (LaproFlex), and fluorescence imaging. RESULTS: The gynecologists experienced an enlarged freedom of movement when using the DROP-IN + LaproFlex combination compared to the rigid laparoscopic probe, making it possible to better isolate the SLN signal from background signals. This did not translate into a change in the SLN find rate yet. In both cervical and endometrial cancer combined, the rigid probe and DROP-IN + LaproFlex combination provided an equivalent detection rate of 96%, while fluorescence provided 85%. CONCLUSION: We have successfully demonstrated the in-human use of steerable DROP-IN radioguidance during laparoscopic cervical and endometrial cancer SLN procedures, expanding the utility beyond robotic procedures. Indicating an improved surgical experience, these findings encourage further investigation and consideration on a path towards routine clinical practice and improved patient outcome. TRIAL REGISTRATION: HCB/2021/0777 and NCT04492995; https://clinicaltrials.gov/study/NCT04492995.

Molecular image-guided surgery in gynaecological cancer: where do we stand?

PURPOSE: The aim of this review is to give an overview of the current status of molecular image-guided surgery in gynaecological malignancies, from both clinical and technological points of view. METHODS: A narrative approach was taken to describe the relevant literature, focusing on clinical applications of molecular image-guided surgery in gynaecology, preoperative imaging as surgical roadmap, and intraoperative devices. RESULTS: The most common clinical application in gynaecology is sentinel node biopsy (SNB). Other promising approaches are receptor-target modalities and occult lesion localisation. Preoperative SPECT/CT and PET/CT permit a roadmap for adequate surgical planning. Intraoperative detection modalities span from 1D probes to 2D portable cameras and 3D freehand imaging. CONCLUSION: After successful application of radio-guided SNB and SPECT, innovation is leaning towards hybrid modalities, such as hybrid tracer and fusion of imaging approaches including SPECT/CT and PET/CT. Robotic surgery, as well as augmented reality and virtual reality techniques, is leading to application of these innovative technologies to the clinical setting, guiding surgeons towards a precise, personalised, and minimally invasive approach.

Nonsentinel Axillary Lymph Node Status in Clinically Node-Negative Early Breast Cancer After Primary Systemic Therapy and Positive Sentinel Lymph Node: A Predictive Model Proposal.

BACKGROUND: In clinically node-negative (cN0) early stage breast cancer (EBC) undergoing primary systemic treatment (PST), post-treatment positive sentinel lymph node (SLN+) directs axillary lymph node dissection (ALND), with uncertain impacts on outcomes and increased morbidities. PATIENTS AND METHODS: We conducted an observational study on imaging-confirmed cN0 EBC, who underwent PST and breast surgery that resulted in SLN+ and underwent ALND. The association among baseline/postsurgical clinic-pathological factors and positive nonsentinel additional axillary lymph nodes (non-SLN+) was analyzed with logistic regression. LASSO regression (LR) identified variables to include in a predictive score of non-SLN+ (ALND-predict). The accuracy and calibration were assessed, an optimal cut-point was then identified, and in silico validation with bootstrap was undertaken. RESULTS: Non-SLN+ were detected in 22.2% cases after ALND. Only progesterone receptor (PR) levels and macrometastatic SLN+ were independently associated to non-SLN+. LR identified PR, Ki67, and type and number of SLN+ as the most efficient covariates. The ALND-predict score was built based on their LR coefficients, showing an area under the curve (AUC) of 0.83 and an optimal cut-off of 63, with a negative predictive value (NPV) of 0.925. Continuous and dichotomic scores had a good fit (p = 0.876 and p = 1.00, respectively) and were independently associated to non-SLN+ [adjusted odds ratio (aOR): 1.06, p = 0.002 and aOR: 23.77, p < 0.001, respectively]. After 5000 bootstrap-adjusted retesting, the estimated bias-corrected and accelerated 95%CI included the aOR. CONCLUSIONS: In cN0 EBC with post-PST SLN+, non-SLN+ at ALND are infrequent (~22%) and independently associated to PR levels and macrometastatic SLN. ALND-predict multiparametric score accurately predicted absence of non-SLN involvement, identifying most patients who could be safely spared unnecessary ALND. Prospective validation is required.

Setting-up a training programme for intraoperative molecular imaging and sentinel node mapping: how to teach? How to learn?

BACKGROUND: The current expansion of image-guided surgery is closely related to the role played by radio-guided surgery in supporting the sentinel node (SN) procedure during more than three decades. The so-called triple approach (lymphoscintigraphy, gamma probe detection and blue dye) was not only essential in the seminal validation of the SN procedure but also a first collective learning effort based on skill transfer and outcome-related evaluation which laid the fundaments to delineate the field of intraoperative molecular imaging (IMI) based on a similar multimodality approach and multidisciplinary practice. METHODS: These elements are also becoming valid in the current incorporation of SPECT/CT and PET/CT to existing and new protocols of IMI procedures and SN mapping concerning other clinical applications. On the other hand, there is a growing tendency to combine novel modern technologies in an allied role with gamma guidance in the operating room following the development of hybrid tracers and multimodal detection approaches. Against this background, learning initiatives are required for professionals working in this area. RESULTS: This objective has led to a group of European practitioners with large experience in SN mapping and IMI applications to give shape to a programme made up out of specific learning modules aimed to be used as a conductive thread in peripherical or centralised training instances concerning the topic. CONCLUSION: The presented work, written as a tutorial review, is placed in an available prior-art context and is primarily aimed at medical and paramedical practitioners as well as at hardware and software developers.

99mTc-Tilmanocept performance for sentinel node mapping in breast cancer, melanoma, and head and neck cancer: a systematic review and meta-analysis from a European expert panel.

PURPOSE: Although multiple radiopharmaceuticals are currently available for sentinel node (SN) biopsy, 99mTc-tilmanocept is of particular interest due to its low molecular weight and specific binding capability for the mannose receptors of lymphatic reticuloendothelial cells. In the current systematic review and meta-analysis, we aimed to provide an update from a European expert panel on the performance of 99mTc-tilmanocept for SN biopsy. METHODS: A systematic literature search of the PubMed/Medline and Embase databases was performed to identify studies on the use of 99mTc-tilmanocept for SN identification in oncological patients. The articles' methodological quality was assessed before inclusion. The pooled estimates of the pre-/intraoperative detection rates (DR; proportion of patients with ≥ 1 SN identified) and/or pN + sensitivity (SN + /pN + patients ratio), with 95% confidence intervals (CIs), were calculated for breast cancer, melanoma, and head and neck cancer. RESULTS: Twenty-four articles were included in the systematic review, and twenty-one provided data for the meta-analysis. According to data availability, the 99mTc-tilmanocept-estimated pooled preoperative and intraoperative DRs were 0.94 (95%CI, 0.88-1.01) and 0.99 (0.98-1.00) for breast cancer, 0.98 (0.96-0.99) and 1.00 (0.99-1.00) for melanoma, and 0.97 (0.93-1.02) and 0.99 (0.96-1.01) for head and neck carcinoma. Finally, the pooled sensitivity for nodal metastasis in melanoma was 0.97 (95% CI, 0.92-1.03). CONCLUSION: 99mTc-tilmanocept is a promising radiotracer for SN mapping in patients with breast cancer, melanoma, or head and neck cancer. We strongly believe that multicenter trials are still needed to assess if 99mTc-tilmanocept is superior to other radiotracers used in clinical routine.

Delphi consensus project on prostate-specific membrane antigen (PSMA)-targeted surgery-outcomes from an international multidisciplinary panel.

PURPOSE: Prostate-specific membrane antigen (PSMA) is increasingly considered as a molecular target to achieve precision surgery for prostate cancer. A Delphi consensus was conducted to explore expert views in this emerging field and to identify knowledge and evidence gaps as well as unmet research needs that may help change practice and improve oncological outcomes for patients. METHODS: One hundred and five statements (scored by a 9-point Likert scale) were distributed through SurveyMonkey®. Following evaluation, a consecutive second round was performed to evaluate consensus (16 statements; 89% response rate). Consensus was defined using the disagreement index, assessed by the research and development project/University of California, Los Angeles appropriateness method. RESULTS: Eighty-six panel participants (72.1% clinician, 8.1% industry, 15.1% scientists, and 4.7% other) participated, most with a urological background (57.0%), followed by nuclear medicine (22.1%). Consensus was obtained on the following: (1) The diagnostic PSMA-ligand PET/CT should ideally be taken < 1 month before surgery, 1-3 months is acceptable; (2) a 16-20-h interval between injection of the tracer and surgery seems to be preferred; (3) PSMA targeting is most valuable for identification of nodal metastases; (4) gamma, fluorescence, and hybrid imaging are the preferred guidance technologies; and (5) randomized controlled clinical trials are required to define oncological value. Regarding surgical margin assessment, the view on the value of PSMA-targeted surgery was neutral or inconclusive. A high rate of "cannot answer" responses indicates further study is necessary to address knowledge gaps (e.g., Cerenkov or beta-emissions). CONCLUSIONS: This Delphi consensus provides guidance for clinicians and researchers that implement or develop PSMA-targeted surgery technologies. Ultimately, however, the consensus should be backed by randomized clinical trial data before it may be implemented within the guidelines.

Mapping sentinel lymph nodes in early-stage ovarian cancer (MELISA) trial - a further step towards lymphadenectomy replacement.

OBJECTIVE: Sistematic pelvic and para-aortic lymphadenectomy is part of the staging surgery for early-stage epithelial ovarian cancer, with no therapeutic value. The Mapping Sentinel Lymph Nodes In Early-Stage Ovarian Cancer (MELISA) trial prospectively assessed the SLN detection rate and the diagnostic accuracy of the SLN mapping technique in patients with early-stage epithelial ovarian cancer. METHODS: This prospective, single-arm study included patients diagnosed with early-stage epithelial ovarian cancer (FIGO stages I and II), via either primary surgery or re-staging surgery. SLN mapping was performed by injecting 0.2 mL of 37-mBq 99mTc-nanocoloid albumin and 2 mL of 2.5 mg/mL indocyanine green into the infundibulopelvic and utero-ovarian ligaments. After removal of SLNs, a complete systematic pelvic and para-aortic lymphadenectomy was performed. SLN Ultrastaging analysis was applied. The primary outcome was the overall SLN detection rate, either with one or both tracers. Secondary outcomes were the diagnostic accuracy of detecting lymph node metastases and factors that may influence SLN detection. RESULTS: Thirty patients were included. SLNs were identified in 27 patients (90%). Detection rates in primary and re-staging surgery were 89% and 92%, respectively. Para-aortic drainage was the predominant lymphatic spread, observed in 26 of 27 patients. Ultrastaging pathologic reports listed 1 SLN with macrometastasis, 1 with micrometastasis, and 5 with isolated tumor cells; the sensitivity of SLN mapping was 100%, with a false-negative rate of 0%. Univariate analysis showed a nonsignificant higher proportion of patients with uterine fibroids, adenomyosis, and endometriosis (100%, 67%, 67%, respectively) in patients in whom SLNs were not detected. CONCLUSION: SLN mapping has a high detection rate (90%) and is an accurate technique for detecting lymph node involvement in early-stage epithelial ovarian cancer. SLN mapping is a potential alternative to systematic lymphadenectomy to reduce associated morbidity, but further research is needed to evaluate the impact of SLN mapping on oncologic outcomes and its cost-effectiveness.

Predictive factors of preoperative sentinel lymph node detection in intermediate and high-risk endometrial cancer.

BACKGROUND: In endometrial cancer (EC), sentinel lymph node (SLN) mapping has emerged as an alternative to systematic lymphadenectomy. Little is known about factors that might influence SLN preoperative detection. The aim of our study was to evaluate the clinical and technical variables that may influence on the success of SLN detection in preoperative lymphatic mapping in patients with intermediate and high-risk EC when performing transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR). METHODS: Between March 2006 and March 2017, we prospectively enrolled patients with histologically confirmed EC with intermediate or high-risk of lymphatic involvement. All women underwent SLN detection by using TUMIR approach. After radiotracer injection, pelvic and abdominal planar and SPECT/CT images were acquired to obtain a preoperative lymphoscintigraphic mapping. Pattern of drainage was registered and analyzed to identify the factors directly involved in drainage. Sonographer learning curves to perform TUMIR approach were created following Cumulative Sum and Wright methods. Univariate and multivariate analyses were performed using logistic regression. RESULTS: During study period, 123 patients were included. SLN preoperative detection rate was 70.7%. Age under 75 years at diagnosis (P<0.01), radiotracer injection above 4 mL -high-volume- (P<0.01), and tumoral size below 2 cm (P=0.04) were associated with higher SLN preoperative detection rate. Twenty-five procedures were necessary to attain an adequate performance in TUMIR approach. CONCLUSIONS: The higher SLN preoperative detection rate in women with intermediate and high-risk endometrial cancer after TUMIR approach was related with younger age, smaller tumors and high-volume injection of radiotracer. Sonographers are required to perform 25 procedures before acquiring an expertise in radiotracer injection.

Sentinel lymph node detection in early-stage ovarian cancer: a systematic review and meta-analysis.

BACKGROUND: A systematic pelvic and para-aortic lymphadenectomy remains the surgical standard management of early-stage epithelial ovarian cancer. Sentinel lymph node mapping is being investigated as an alternative procedure; however, data reporting sentinel lymph node performance are heterogeneous and limited. OBJECTIVE: This study aimed to evaluate the detection rate and diagnostic accuracy of sentinel lymph node mapping in patients with early-stage ovarian cancer. METHODS: A systematic search was conducted in Medline (through PubMed), Embase, Scopus, and the Cochrane Library. We included patients with clinical stage I-II ovarian cancer undergoing a sentinel lymph node biopsy and a pelvic and para-aortic lymphadenectomy as a reference standard. We conducted a meta-analysis for the detection rates and measures of diagnostic accuracy and assessed the risk of bias using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO) with identifying number CRD42022351497. RESULTS: After duplicate removal, we identified 540 studies, 18 were assessed for eligibility, and nine studies including 113 patients were analyzed. The pooled detection rates were 93.3% per patient (95% CI 77.8% to 100%; I2=74.3%, p<0.0001), and the sentinel lymph node technique correctly identified 11 of 12 patients with lymph node metastases, with a negative predictive value per patient of 100% (95% CI 97.6% to 100%; I2=0%). The combination of indocyanine green and 99mTc-albumin nanocolloid had the best detection rate (100% (95% CI 94% to 100%; I2=0%)) when injected into the utero-ovarian and infundibulo-pelvic ligaments. CONCLUSION: Sentinel lymph node biopsy in early-stage ovarian cancer showed a high detection rate and negative predictive value. The utero-ovarian and infundibulo-pelvic injection using the indocyanine green and technetium-99 combination could increase sentinel lymph node detection rates. However, given the limited quality of evidence and the small number of reports, results from ongoing trials are awaited before its implementation in routine clinical practice.

Role of a portable gamma-camera with optical view for margins assessment of pulmonary nodules resected by radioguided surgery.

PURPOSE: Radioguided occult lesion localization (ROLL) of pulmonary nodules is an alternative to hook-wire. Both required of a histological margin assessment. The activity emerging from the radiotracer allows to obtain an intraoperative scintigraphic image of the surgical specimen by a portable gamma-camera (PGC) fitted with an optical view, which provides information about the localization of the nodule in relation to the margins. The aim of this study was to evaluate the intraoperative use of a PGC for margin assessment of pulmonary nodules. METHODS: ROLL technique was used in 38 nodules (36 pulmonary, 1 chest wall, and 1 pleural nodules). A PGC intraoperative image of the surgical specimen was obtained in 32. Scintigraphic results were compared to the histological assessment. Other factors, such as nodule size, distance from the pleural surface, or distance covered by the needle, were considered as possible factors for non-centered lesions. RESULTS: PGC images showed that the lesion was in contact with the margins in 8/32 cases and centered in 24. In all cases in which the lesion was considered as centered by the PGC, the margins were free of involvement (NPV 100%), although the PPV is low. CONCLUSIONS: The use of a PGC for margin assessment after pulmonary nodule resection is feasible and provides a high NPV in our series. In addition, the short intraoperative time required for its use makes the PGC a useful tool for providing supplementary information to histopathologic results. Further studies from different surgical teams are required for an external validation.

Correlation between ferromagnetic and isotopic tracers for sentinel lymph node detection in cutaneous melanoma: IMINEM study.

BACKGROUND: The usefulness of sentinel lymph node biopsy (SLNB) in staging cutaneous melanoma has been proven. Therefore, different tracers have been used to identify the sentinel lymph nodes (SLNs). The use of isotopic tracers together with radioactivity detectors allowed a much more precise and direct approach to the SLNs. However, not all centres have access to a Nuclear Medicine department hindering sentinel lymph node detection (SLND) and consequently, other markers such as ferromagnetic tracers have been evaluated looking for the same advantages and effectiveness as isotopic tracers. Ferromagnetic tracers have proven their usefulness in other cancer entities such as breast, prostate and thyroid cancer. The objective was to assess the detection and concordance rates between isotopic and ferromagnetic techniques for SLNB in cutaneous melanoma. METHOD: Isotopic SLNB technique and ferromagnetic tracer were compared for cutaneous melanoma in a non-inferiority multicentre prospective study carried out in six Spanish hospitals. RESULTS: A total of 60 patients were recruited and 133 lymph nodes removed. The detection rate was slightly higher with ferromagnetic tracer in head-neck and trunk melanomas, and with isotopic tracer in limbs. The patients' and nodes' concordance rates between both techniques for ex vivo samples were 95% and 86% for head-neck and trunk tumours and 97% and 93% for limbs tumours, respectively. The concordance rates for involved nodes were 100% and 88.2% for patients and nodes, respectively. CONCLUSION: The intraoperative detection and biopsy of SLN in cutaneous melanoma using a ferromagnetic was a reliable alternative method to the isotopic technique in cutaneous melanomas.

Contemporary update of SPECT tracers and novelties in radioguided surgery: a perspective based on urology.

Recent technical advances and implementation of novel radiotracers have further increased the potential of radioguided surgery for a broad variety of malignancies. Indeed, the possibilities for future applications of novel radiotracers in diverse oncological strategies has become more promising than ever. This literature review aims to provide a contemporary update on a selected group of radiotracers and evaluates the usability of radioguided surgery and sentinel node procedures, focusing on most promising advances. For example, the impact of targeted radiotracers on prostate specific membrane antigen (PSMA), CD206 receptor-targeted agents (99mTc-tilmanocept), and hybrid tracers adding fluorescence to radioguidance (ICG-99mTc-nanocolloid) as well as targeting hypoxia-induced carbonic anhydrase IX (CAIX) will be covered. Furthermore, future outlooks on the implementation of gold nanoparticles (AuNP's), but also technical advances in improved radiotracer detection by hybrid gamma devices will be discussed.

Completion Dissection or Observation for Sentinel-Node Metastasis in Melanoma.

BACKGROUND: Sentinel-lymph-node biopsy is associated with increased melanoma-specific survival (i.e., survival until death from melanoma) among patients with node-positive intermediate-thickness melanomas (1.2 to 3.5 mm). The value of completion lymph-node dissection for patients with sentinel-node metastases is not clear. METHODS: In an international trial, we randomly assigned patients with sentinel-node metastases detected by means of standard pathological assessment or a multimarker molecular assay to immediate completion lymph-node dissection (dissection group) or nodal observation with ultrasonography (observation group). The primary end point was melanoma-specific survival. Secondary end points included disease-free survival and the cumulative rate of nonsentinel-node metastasis. RESULTS: Immediate completion lymph-node dissection was not associated with increased melanoma-specific survival among 1934 patients with data that could be evaluated in an intention-to-treat analysis or among 1755 patients in the per-protocol analysis. In the per-protocol analysis, the mean (±SE) 3-year rate of melanoma-specific survival was similar in the dissection group and the observation group (86±1.3% and 86±1.2%, respectively; P=0.42 by the log-rank test) at a median follow-up of 43 months. The rate of disease-free survival was slightly higher in the dissection group than in the observation group (68±1.7% and 63±1.7%, respectively; P=0.05 by the log-rank test) at 3 years, based on an increased rate of disease control in the regional nodes at 3 years (92±1.0% vs. 77±1.5%; P<0.001 by the log-rank test); these results must be interpreted with caution. Nonsentinel-node metastases, identified in 11.5% of the patients in the dissection group, were a strong, independent prognostic factor for recurrence (hazard ratio, 1.78; P=0.005). Lymphedema was observed in 24.1% of the patients in the dissection group and in 6.3% of those in the observation group. CONCLUSIONS: Immediate completion lymph-node dissection increased the rate of regional disease control and provided prognostic information but did not increase melanoma-specific survival among patients with melanoma and sentinel-node metastases. (Funded by the National Cancer Institute and others; MSLT-II ClinicalTrials.gov number, NCT00297895 .).

Lymphoscintigraphy and sentinel lymph node biopsy in vulvar carcinoma: update from a European expert panel.

PURPOSE: This study aimed to update the clinical practice applications and technical procedures of sentinel lymph node (SLN) biopsy in vulvar cancer from European experts. METHODS: A systematic data search using PubMed/MEDLINE database was performed up to May 29, 2019. Only original studies focused on SLN biopsy in vulvar cancer, published in the English language and with a minimum of nine patients were selected. RESULTS: Among 280 citations, 65 studies fulfilled the inclusion criteria. On the basis of the published evidences and consensus of European experts, this study provides an updated overview on clinical applications and technical procedures of SLN biopsy in vulvar cancer. CONCLUSIONS: SLN biopsy is nowadays the standard treatment for well-selected women with clinically negative lymph nodes. Negative SLN is associated with a low groin recurrence rate and a good 5-year disease-specific survival rate. SLN biopsy is the most cost-effective approach than lymphadenectomy in early-stage vulvar cancer. However, future trials should focus on the safe extension of the indication of SLN biopsy in vulvar cancer. Although radiotracers and optical agents are widely used in the clinical routine, there is an increasing interest for hybrid tracers like indocyanine-99mTc-nanocolloid. Finally, it is essential to standardise the acquisition protocol including SPECT/CT images, and due to the low incidence of this type of malignancy to centralise this procedure in experienced centres for personalised approach.

Applicability of sentinel lymph node biopsy in papillary thyroid cancer.

BACKGROUND: The optimal surgical management of papillary thyroid cancer (PTC) for T1-T2 tumors without pre or intrasurgical evidence of lymph node metastasis (cN0) remains controversial, since approximately 40% of patients have lymph node involvement (pN1) which becomes evident when a prophylactic lymphadenectomy (PL) is performed. The aim of this study was to investigate the feasibility of sentinel lymph node (SLN) identification with SPECT/CT lymphoscintigraphy imaging along with intraoperatory image techniques in early stages of PTC undergoing PL of central neck compartment (CNC). METHODS: A single-center, prospective consecutive study was designed for SLN mapping in patients with high suspicion of PTC (Bethesda V or VI) in early stage (cT1-2, cN0). Twenty-four patients underwent SLN identification with preoperative SPECT/CT and planar images (99mTc-nanocolloid albumin intratumoral injection). During surgery, SLN located in CNC was found by means of a gamma probe and portable gamma camera, and excised. Afterwards, CNC lymphadenectomy was performed in all cases without modifying the established protocol. RESULTS: SLNs were identified and accurately located in 23 (95.8%) patients. Nodal metastases (pN1) were confirmed in 9 (37.5%) patients, with one false negative case. The sensitivity was 88.9% and negative predictive value (NPV) was 93.3%, would have allowed to avoid PL in more than half of cases, a higher proportion than those found in other similar studies. No complications associated with the procedure were observed. CONCLUSIONS: Our results support that SLN biopsy by SPECT/CT along with intraoperatory image techniques is applicable in early stages of PTC (cT1-2, cN0), allowing to avoid unnecessary PL.

Use of Radioactive Seed Localization to Guide Removal of a Nonpalpable Endometriotic Lesion: A Case Report.

Extrapelvic endometriosis is a rare and usually misdiagnosed entity. Some extrapelvic endometriotic lesions are small and nonpalpable, which makes them difficult to locate and remove. Here, we report the use of radioactive seed localization to locate and guide the excision of a small, nonpalpable endometriotic lesion. A 32-year-old woman presented with disabling pain in the right inguinal area. Magnetic resonance imaging and abdominal ultrasound results showed an 11-mm nodule in the abdominal wall, in the vicinity of the groin, consistent with an endometriotic lesion. The radioactive seed was placed within the lesion with the help of ultrasonography, and excision was guided with a portable gamma camera. Complete excision of the endometriotic nodule was achieved. We propose radioactive seed localization as an accurate and feasible technique for the treatment of nonpalpable endometriotic lesions.

Diagnostic accuracy of imaging studies for initial staging of T2b to T4b melanoma patients: A cross-sectional study.

BACKGROUND: There is no consensus on the imaging tests that should be performed at the initial staging of melanoma patients. OBJECTIVE: To evaluate the diagnostic accuracy of 4 imaging studies for the initial staging of melanoma patients. METHODS: Cross-sectional study with prospectively collected data, from January 2011 to April 2017, including patients with clinical stage T2b to T4b according to 2009 American Joint Committee on Cancer, without evidence of metastasis. RESULTS: Initial staging of 308 patients detected 16.6% of metastases and 5.8% false-positive results, overall. Regional lymph node ultrasonography showed a metastasis detection rate (MDR) of 12.8%, false-positive rate of 0.8%, and accuracy of 96.0%. Computed tomography (CT) and positron emission tomography-CT had the highest detection rates at stage T4b: MDR, 13.3%; false-positive rate, 8.9%; accuracy, 91.1%; and MDR, 6.9%; false-positive rate, 0%; and accuracy, 93.1%, respectively. Brain magnetic resonance imaging showed a MDR of 2.0% in T4b. LIMITATIONS: Single-center study. CONCLUSION: Performing ultrasound scans for assessing lymph node metastasis in patients with American Joint Committee on Cancer T2b stage and above is advisable. In patients with stage T4b, CT or positron emission tomography-CT are suitable for the detection of metastasis. Brain magnetic resonance imaging at T4b deserves further discussion, considering the ultimate clinical benefit in management and therapeutic options for asymptomatic patients.

Sentinel lymph node biopsy versus observation in thick melanoma: A multicenter propensity score matching study.

The clinical value of sentinel lymph node (SLN) biopsy in thick melanoma patients (Breslow >4 mm) has not been sufficiently studied. The aim of the study is to evaluate whether SLN biopsy increases survival in patients with thick cutaneous melanoma, and, as a secondary objective, to investigate correlations between survival and lymph node status. We included 1,211 consecutive patients with thick melanomas (>4 mm) registered in the participating hospitals' melanoma databases between 1997 and 2015. Median follow-up was 40 months. Of these patients, 752 were matched into pairs by propensity scores based on sex, age, tumor location, histologic features of melanoma, year of diagnosis, hospital and adjuvant interferon therapy. The SLN biopsy vs. observation was associated with better DFS [adjusted hazard ratio (AHR), 0.74; 95% confidence interval (CI) 0.61-0.90); p = 0.002] and OS (AHR, 0.75; 95% CI, 0.60-0.94; p = 0.013) but not MSS (AHR, 0.84; 95% CI, 0.65-1.08; p = 0.165). SLN-negative patients had better 5- and 10-year MSS compared with SLN-positive patients (65.4 vs. 51.9% and 48.3 vs. 38.8%; p = 0.01, respectively). As a conclusion, SLN biopsy was associated with better DFS but not MSS in thick melanoma patients after adjustment for classic prognostic factors. SLN biopsy is useful for stratifying these patients into different prognostic groups.