Preoperative sentinel node mapping with 99mTc-nanocolloid SPECT–CT significantly reduces the intraoperative sentinel node retrieval time in robot assisted laparoscopic cervical cancer surgery

Validation of single-photon emission computed tomography with computed tomography and lymphoscintigraphy for sentinel lymph node identification in cervical cancer

OBJECTIVE

To compare single-photon emission computed tomography with computed tomography (SPECT/CT) and lymphoscintigraphy (LSG) for the detection of sentinel lymph nodes (SLNs) in patients with early-stage cervical cancer.

METHODS

This hospital-based, single-center, retrospective study included 128 patients with cervical cancer (aged >18 years) treated between 2014 and 2022. Injection of 99 m Technetium-labeled phytate into the uterine cervix was used to detect pelvic SLNs. SNL identification rates and locations were analyzed for preoperative LSG and SPECT/CT.

RESULTS

Median age and body mass index of patients were 40 years (range, 20-78 years) and 21.7 kg/m2 (range, 16-40 kg/m2 ), respectively. There was no significant difference in overall identification rates (identification of at least one SLN) of SLNs between SPECT/CT (91%) and LSG (88%). There was no significant difference in bilateral SLN identification rates between SPECT/CT (66%) and LSG (65%). A total of 219 pelvic SLNs (110 right and 109 left hemipelvis) were identified by SPECT/CT; the most frequent locations were the obturator (122 SLNs, 56%) and external iliac (67 SLNs, 30%).

CONCLUSION

SPECT/CT and LSG showed high SLN identification rates in patients with cervical cancer, and there was no significant difference in overall or bilateral SLN identification rates between the two techniques.

Fluorescent Indocyanine Green versus Technetium-99m and Blue Dye for Bilateral SENTinel Lymph Node Detection in Stage I-IIA Cervical Cancer (FluoreSENT): protocol for a non-inferiority study

INTRODUCTION

Nowadays, two predominant methods for detecting sentinel lymph nodes (SLNs) in cervical cancer are in use. The most conventional method is a combination of a radiotracer, technetium-99m (^99mTc) and blue dye. More recently, another method for SLN mapping using indocyanine green (ICG) is becoming widely accepted. ICG is a fluorescent dye, visualised intraoperatively with near-infrared (NIR) fluorescence imaging, providing real-time visual navigation. The presumed advantages of ICG over ^99mTc, that is, being cheaper, non-radioactive and logistically more attractive, are only valuable if its detection rate proves to be at least non-inferior. Before omitting the well-functioning and evidence-based combined approach of ^99mTc and blue dye, we aim to provide prospective evidence on the non-inferiority of ICG with NIR fluorescence imaging.

METHODS AND ANALYSIS

We initiated a prospective non-inferiority study with a paired comparison of both SLN methods in a single sample of 101 patients with International Federation of Gynecology and Obstetrics (FIGO) stage IA-IB2 or IIA1 cervical cancer receiving primary surgical treatment. All patients undergo SLN mapping with ICG and NIR fluorescence imaging in adjunct to mapping with ^99mTc (including single photon emission computed tomography with X-ray computed tomography (SPECT/CT)) and blue dye. Surgeons start SLN detection with ICG while being blinded for the preoperative outcome of SPECT/CT to avoid biased detection with ICG. Primary endpoint of this study is bilateral SLN detection rate of both methods (ie, detection of at least one SLN in each hemipelvis). Since we compare strategies for SLN mapping that are already applied in current daily practice for different types of cancer, no additional risks or burdens are expected from these study procedures.

ETHICS AND DISSEMINATION

The current study is approved by the Medical Ethics Research Committee Utrecht (reference number 21-014). Findings arising from this study will be disseminated in peer-reviewed journals, academic conferences and through patient organisations.

TRIAL REGISTRATION NUMBER

NL9011 and EudraCT 2020-005134-15.

Feasibility of a drop-in γ-probe for radioguided sentinel lymph detection in early-stage cervical cancer

Background

Minimally invasive radioguided sentinel lymph node (SLN) procedures, increasingly performed with robot-assisted laparoscopy, can benefit from using a drop-in γ-probe instead of the conventional rigid laparoscopic γ-probe. We evaluated the safety and feasibility of a tethered drop-in γ-probe system for SLN detection in patients with early-stage cervical cancer.

Methods

Ten patients with FIGO stage IA – IB2 or IIA1 cervical cancer scheduled for robot-assisted laparoscopic SLN procedure were included. All patients underwent preoperative 240 MBq technetium-99m nanocolloid (^99mTc) injection and SPECT/CT imaging. Intraoperatively the tethered drop-in γ-probe SENSEI® (Lightpoint Medical Ltd, Chesham, UK) was used for probe guided SLN detection, subsequently confirmed by the standard rigid laparoscopic γ-probe. Sentinel lymph node detection rates and anatomical SLN location were assessed. Surgeon questionnaires were used to assess usability.

Results

In all patients at least one SLN was successfully resected under guidance of the drop-in γ-probe (overall detection rate: 100%). Bilateral SLN detection rate with the drop-in γ-probe was 80%. Of the two patients with unilateral SLN detection only, one presented with an atypical SLN location at the aortic bifurcation that was detected only on SPECT/CT. The other patient had failed unilateral ^99mTc uptake. Combined use of preoperative SPECT/CT and drop-in γ-probe resulted in a bilateral detection rate of 90%. Similar to the drop-in γ-probe, overall and bilateral SLN detection rate of the rigid γ-probe was 100% and 80%, respectively. No significant discrepancy existed between the count rate of the drop-in and rigid laparoscopic γ-probe (p = 0.69). In total 21 SLN’s were detected with the drop-in γ-probes including all three tumor positive nodes. Because of wristed articulation of the robotic tissue grasper and possibility of autonomous probe control by the surgeon, maneuverability and control with the drop-in γ-probe were highly rated in surgeon questionnaires. No adverse events related to the intervention occurred.

Conclusions

Sentinel lymph node detection with a drop-in γ-probe is safe and feasible in patients with early-stage cervical cancer. Use of the drop-in γ-probe enhances maneuverability and surgical autonomy during robot-assisted SLN detection.

Trial registration Netherlands Trial Registry, NL9358. Registered 23 March 2021, https://www.trialregister.nl/trial/9358.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13550-022-00907-w.

Sentinel node navigation surgery in cervical cancer: a systematic review and metaanalysis

Sentinel node navigation surgery (SNNS) is used in clinical practice for the treatment of cervical cancer. This study aimed to elucidate the appropriate sentinel lymph node (SLN) mapping method and assess the safety and benefits of SNNS. We searched the PubMed, Ichushi, and Cochrane Library databases for randomized controlled trials (RCT) and studies on SLN in cervical cancer from January 2012 to December 2020. Two authors independently assessed study quality and extracted data. We quantitatively analyzed the detection rate, sensitivity/specificity, and complications and reviewed information, including the survival data of SLN biopsy (SLNB) without pelvic lymphadenectomy (PLND). The detection rate of SLN mapping in the unilateral pelvis was median 95.7% and 100% and in the bilateral pelvis was median 80.4% and 90% for technetium-99 m (Tc) with/without blue dye (Tc w/wo BD) and indocyanine green (ICG) alone, respectively. The sensitivity and specificity of each tracer were high; the area under the curve of each tracer was 0.988 (Tc w/wo BD), 0.931 (BD w/wo Tc), 0.966 (ICG), and 0.977 (carbon nanoparticle). Morbidities including lymphedema, neurological symptoms and blood loss were associated with PLND. One RCT and five studies all showed SNNS without systematic PLND does not impair recurrence or survival in early-stage cervical cancer with a tumor size ≤ 2-4 cm. Both Tc w/wo BD and ICG are appropriate SLN tracers. SNNS can reduce the morbidities associated with PLND without affecting disease progression in early-stage cervical cancer.

Indocyanine green versus technetium-99m with blue dye for sentinel lymph node detection in early-stage cervical cancer: A systematic review and meta-analysis

Background

The fluorescent dye indocyanine green (ICG) has emerged as a promising tracer for intraoperative detection of sentinel lymph nodes (SLNs) in early‐stage cervical cancer. Although researchers suggest the SLN detection of ICG is equal to the more conventional combined approach of a radiotracer and blue dye, no consensus has been reached.

Aims

We aimed to assess the differences in overall and bilateral SLN detection rates with ICG versus the combined approach, the radiotracer technetium‐99m (^99mTc) with blue dye.

Methods and Results

We searched MEDLINE, Embase, and the Cochrane Library from inception to January 1, 2020 and included studies reporting on a comparison of SLN detection with ICG versus ^99mTc with blue dye in early‐stage cervical cancer. The overall and bilateral detection rates were pooled with random‐effects meta‐analyses.

From 118 studies retrieved seven studies (one cross‐sectional; six retrospective cohorts) were included, encompassing 589 patients. No significant differences were found in the pooled overall SLN detection rate of ICG versus ^99mTc with blue dye. Meta‐analyses of all studies showed ICG to result in a higher bilateral SLN detection rate than ^99mTc with blue dye; 90.3% (95%CI, 79.8‐100.0%) with ICG versus 73.5% (95%CI, 66.4‐80.6%) with 99mTc with blue dye. This resulted in a significant and clinically relevant risk difference of 16.6% (95%CI, 5.3‐28.0%). With sensitivity analysis, the risk difference of the bilateral detection rate maintained in favor of ICG but was no longer significant (13.2%, 95%CI −0.8‐27.3%).

Conclusion

ICG appears to provide higher bilateral SLN detection rates compared to ^99mTc with blue dye in patients with early‐stage cervical cancer. However, in adherence with the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) guidelines, the quality of evidence is too low to provide strong recommendations and directly omit the combined approach of ^99mTc with blue dye.

The influence of learning curve of robot-assisted laparoscopy on oncological outcomes in early-stage cervical cancer: an observational cohort study

OBJECTIVE

To investigate the learning curve of robot-assisted laparoscopy in early-stage cervical cancer and quantify impact on oncological outcomes.

DESIGN

Observational cohort study.

SETTING

Tertiary referral centre with one surgical team.

POPULATION

All women with early-stage cervical cancer treated consecutively with robot-assisted laparoscopy between 2007 and 2017.

METHODS

With multivariate risk-adjusted cumulative sum analysis (RA-CUSUM), we assessed the learning curve of robot-assisted laparoscopy of a single surgical team based on cervical cancer recurrence. Subsequently, a survival analysis was conducted comparing oncological outcomes of women treated during different phases of the learning curve.

MAIN OUTCOME MEASURES

Surgical proficiency based on recurrence, survival rates in the different learning phases.

RESULTS

One hundred and sixty-five women with cervical cancer underwent robot-assisted laparoscopy, with a median follow up of 57 months (range 3-132 months). The RA-CUSUM analysis demonstrated two phases of the learning curve: a learning phase of 61 procedures (group 1) and an experienced phase representing the 104 procedures thereafter (group 2). The 5-year disease-free survival was 80.2% in group 1 and 91.1% in group 2 (P = 0.040). Both the 5-year disease-specific survival and overall survival significantly increased after the learning phase.

CONCLUSION

The learning phase of robot-assisted laparoscopy in early-stage cervical cancer in this institutional cohort is at least 61 procedures, with higher survival rates in the women treated thereafter. The learning curve of robot-assisted laparoscopy affects oncological outcomes and warrants more attention in the design of future studies.

TWEETABLE ABSTRACT

The learning curve of robot-assisted laparoscopy in early-stage cervical cancer affects oncological outcomes and warrants more attention.

Interventional nuclear medicine: a focus on radioguided intervention and surgery

Within interventional nuclear medicine (iNM) a prominent role is allocated for the sub-discipline of radioguided surgery. Unique for this discipline is the fact that an increasing number of clinical indications (e.g. lymphatic mapping, local tumor demarcation and/or tumor receptor targeted applications) have been adopted into routine care. The clinical integration is further strengthened by technical innovations in chemistry and engineering that enhance the translational potential of radioguided procedures in iNM. Together, these features not only ensure ongoing expansion of iNM but also warrant a lasting clinical impact for the sub-discipline of radioguided surgery.

Sentinel lymph node in cervical cancer: a literature review on the use of conservative surgery techniques

INTRODUCTION

Sentinel lymph node detection is a surgical procedure that allow to avoid systematic lymphadenectomy in those tumors in early stage where lymph node spread is not sure. If the sentinel lymph node is not involved by tumor in 98-99% of case other lymph nodes are clean. The reason why less radical surgery is chosen is linked to the lower postoperative morbidity rate, the risk of lower limb lymphedema decreases. The aim of this review was to summarize what is the state of art of using the sentinel lymph node dissection (SLD) technique and what are the future goals to improve the safety and the reliability.

EVIDENCE ACQUISITION

We have conducted a review of the literature of the past 10 years to understand the attitudes of oncologist gynecologists in the world to the conservative treatment of cervical cancer. We only selected articles from 2010 onwards, which meet the inclusion criteria.

EVIDENCE SYNTHESIS

The detection rate varies from 83% to 100%. The bilateral detection rate, on the other hand, varies from 42% to 100%. The false negative rate ranges from 4% to 12%. Sensitivity varies from 20.7% (considering the frozen section) to 100%.

CONCLUSIONS

Indocyanine green is the most reliable and performing tracer for the search of the sentinel lymph node; that the false intraoperative negative rate is too high to be sure not to subject the patient to an incorrect therapeutic procedure; data concerning the safety and survival of conservative lymphadenectomy (SLND) compared to systematic lymphadenectomy are still lacking in the literature and therefore we are awaiting the results of the two ongoing randomized clinical trials that will allow us to have more significant scientific data.

Fertility-Sparing Surgery Using Knitted TiNi Mesh Implants and Sentinel Lymph Nodes: A 10-Year Experience

Objectives: The aim of this cohort study is to improve the procedure of fertility-sparing surgery and to assess oncological and reproductive follow-up outcomes after radical trachelectomy (RT) for cervical cancer (T_1a2-1bN_xM₀).Methods: We have suggested the method combining sentinel lymph nodes (SLNs) and cervicoisthmic cerclage using a superelastic knitted TiNi mesh (KTNM) implant to facilitate the primary biomechanical/retention function of the uterus. Sixty-eight consented patients, who underwent fertility-sparing surgery using both transabdominal and laparoscopic route from 2009 through 2019, were recruited in the study and prospectively followed for a mean of 69 months.Results: There were no intraoperative or postoperative complications. No cervical stenoses or mesh failures were noted in all cases. The 5-year overall and recurrence-free survival rates were 100% and 97%, respectively. Two patients indicated recurrence, it occurred in 3 and 36 months. There were 19 (28%) spontaneous pregnancies, 6 resulted in full-term delivery, whereas 2 and 11 ended in miscarriage and early abortion, respectively.Conclusions: This sparing-surgery technique is turned out to be feasible and efficient as allows to achieve well oncologic and fertility outcomes, mimicking the effect of the cervix. It complements existing surgical approaches and may provide further insight into how to overcome challenges even in aggravated cases or previously failed procedures.

Pathologic Protocols for Sentinel Lymph Nodes Ultrastaging in Cervical Cancer

CONTEXT.—

Ultrastaging of sentinel lymph nodes (SLNs) is a crucial aspect in the approach to SLN processing. No consensual protocol for pathologic ultrastaging has been approved by international societies to date.

OBJECTIVE.—

To provide a review of the ultrastaging protocol and all its aspects related to the processing of SLNs in patients with cervical cancer.

DATA SOURCES.—

In total, 127 publications reporting data from 9085 cases were identified in the literature. In 24% of studies, the information about SLN processing is entirely missing. No ultrastaging protocol was used in 7% of publications. When described, the differences in all aspects of SLN processing among the studies and institutions are substantial. This includes grossing of the SLN, which is not completely sliced and processed in almost 20% of studies. The reported protocols varied in all aspects of SLN processing, including the thickness of slices (range, 1-5 mm), the number of levels (range, 0-cut out until no tissue left), distance between the levels (range, 40-1000 μm), and number of sections per level (range, 1-5).

CONCLUSIONS.—

We found substantial differences in protocols used for SLN pathologic ultrastaging, which can impact sensitivity for detection of micrometastases and even small macrometastases. Since the involvement of pelvic lymph nodes is the most important negative prognostic factor, such profound discrepancies influence the referral of patients to adjuvant radiotherapy and could potentially cause treatment failure. It is urgent that international societies agree on a consensual protocol before SLN biopsy without pelvic lymphadenectomy is introduced into routine clinical practice.

Recent advances in nuclear and hybrid detection modalities for image-guided surgery

Introduction: Radioguided surgery is an ever-evolving part of nuclear medicine. In fact, this nuclear medicine sub-discipline actively bridges non-invasive molecular imaging with surgical care. Next to relying on the availability of radio- and bimodal-tracers, the success of radioguided surgery is for a large part dependent on the imaging modalities and imaging concepts available for the surgical setting. With this review, we have aimed to provide a comprehensive update of the most recent advances in the field. Areas covered: We have made an attempt to cover all aspects of radioguided surgery: 1) the use of radioisotopes that emit γ, β⁺, and/or β^- radiation, 2) hardware developments ranging from probes to 2D cameras and even the use of advanced 3D interventional imaging solutions, and 3) multiplexing solutions such as dual-isotope detection or combined radionuclear and optical detection. Expert opinion: Technical refinements in the field of radioguided surgery should continue to focus on supporting its implementation in the increasingly complex minimally invasive surgical setting, e.g. by accommodating robot-assisted laparoscopic surgery. In addition, hybrid concepts that integrate the use of radioisotopes with other image-guided surgery modalities such as fluorescence or ultrasound are likely to expand in the future.

Sentinel Lymph Nodes Mapping in Cervical Cancer a Comprehensive Review

Objective

A comprehensive literature search for more recent studies pertaining to sentinel lymph node mapping in the surveillance of cervical cancer to assess if sentinel lymph node mapping has sensitivity and specificity for evaluation of the disease; assessment of posttreatment response and disease recurrence in cervical cancer.

Materials and Methods

The literature review has been constructed on a step wise study design that includes 5 major steps. This includes search for relevant publications in various available databases, application of inclusion and exclusion criteria for the selection of relevant publications, assessment of quality of the studies included, extraction of the relevant data and coherent synthesis of the data.

Results

The search yielded numerous studies pertaining to sentinel lymph node mapping, especially on the recent trends, comparison between various modalities and evaluation of the technique. Evaluation studies have appraised high sensitivity, high negative predictive values and low false-negative rate for metastasis detection using sentinel lymph node mapping. Comparative studies have established that of all the modalities for sentinel lymph node mapping, indocyanine green sentinel lymph node mapping has higher overall and bilateral detection rates. Corroboration of the deductions of these studies further establishes that the sentinel node detection rate and sensitivity are strongly correlated to the method or technique of mapping and the history of preoperative neoadjuvant chemotherapy.

Conclusions

The review takes us to the strong conclusion that sentinel lymph node mapping is an ideal technique for detection of sentinel lymph nodes in cervical cancer patients with excellent detection rates and high sensitivity. The review also takes us to the supposition that a routine clinical evaluation of sentinel lymph nodes is feasible and a real-time florescence mapping with indocyanine green dye gives better statistically significant overall and bilateral detection than methylene blue.

The sentinel node approach in gynaecological malignancies

This review discusses the state-of-the-art of sentinel lymph node mapping in gynaecological malignancies, including cervical cancer, endometrial cancer, and vulvar cancer, with an emphasis on new technological advances. For this objective, PubMed/MEDLINE was searched for relevant studies about the sentinel lymph node procedure in gynaecology. In particular, the use of preoperative lymphatic mapping with lymphoscintigraphy and single photon emission tomography/computed tomography (SPECT/CT) was identified in 18 studies. Other recent advances as hybrid tracers (e.g. ICG-^99mTc-nanocolloid) and intraoperative tools (portable γ-camera and 3D navigation devices) appear to also represent a useful guide for the surgeon during the operation. Concerning vulvar and cervical cancers, the sentinel lymph node procedure has been incorporated to the current guidelines in Europe and North America, whereas for endometrial cancer it is considered investigative.

First Robotic SPECT for Minimally Invasive Sentinel Lymph Node Mapping

In this paper we present the usage of a drop-in gamma probe for intra-operative Single-Photon Emission Computed Tomography (SPECT) imaging in the scope of minimally invasive robot-assisted interventions. The probe is designed to be inserted and reside inside the abdominal cavity during the intervention. It is grasped during the procedure using a robotic laparoscopic gripper enabling full six degrees of freedom handling by the surgeon. We demonstrate the first deployment of the tracked probe for intra-operative in-patient robotic SPECT enabling augmented-reality image guidance. The hybrid mechanical- and image-based in-patient probe tracking is shown to have an accuracy of 0.2 mm. The overall system performance is evaluated and tested with a phantom for gynecological sentinel lymph node interventions and compared to ground-truth data yielding a mean reconstruction accuracy of 0.67 mm.

99mTc-Nanocolloid SPECT/MRI Fusion for the Selective Assessment of Nonenlarged Sentinel Lymph Nodes in Patients with Early-Stage Cervical Cancer

We aimed to explore the accuracy of (99m)Tc SPECT/MRI fusion for the selective assessment of nonenlarged sentinel lymph nodes (SLNs) for diagnosing metastases in early-stage cervical cancer patients.

METHODS

We consecutively included stage IA1-IIB1 cervical cancer patients who presented to our tertiary referral center between March 2011 and February 2015. Patients with enlarged lymph nodes (short axis ≥ 10 mm) on MRI were excluded. Patients underwent an SLN procedure with preoperative (99m)Tc-nanocolloid SPECT/CT-based SLN mapping. When fused datasets of the SPECT and MR images were created, SLNs could be identified on the MR image with accurate correlation to the histologic result of each individual SLN. An experienced radiologist, masked to histology, retrospectively reviewed all fused SPECT/MR images and scored morphologic SLN parameters on a standardized case report form. Logistic regression and receiver-operating curves were used to model the parameters against the SLN status.

RESULTS

In 75 cases, 136 SLNs were eligible for analysis, of which 13 (9.6%) contained metastases (8 cases). Three parameters-short-axis diameter, long-axis diameter, and absence of sharp demarcation-significantly predicted metastatic invasion of nonenlarged SLNs, with quality-adjusted odds ratios of 1.42 (95% confidence interval [CI], 1.01-1.99), 1.28 (95% CI, 1.03-1.57), and 7.55 (95% CI, 1.09-52.28), respectively. The area under the curve of the receiver-operating curves combining these parameters was 0.749 (95% CI, 0.569-0.930). Heterogeneous gadolinium enhancement, cortical thickness, round shape, or SLN size, compared with the nearest non-SLN, showed no association with metastases (P= 0.055-0.795).

CONCLUSION

In cervical cancer patients without enlarged lymph nodes, selective evaluation of only the SLNs-for size and absence of sharp demarcation-can be used to noninvasively assess the presence of metastases.

The Added Value of SPECT/CT in Sentinel Lymph Nodes Mapping for Endometrial Carcinoma

OBJECTIVES

This study was designed to evaluate the detection rate (DR) and sensitivity of sentinel lymph node (SLN) mapping in patients with endometrial cancer using TC99m colloid and blue dye and to evaluate the contribution of preoperative planar lymphoscintigraphy (PLSG) and SPECT/CT.

METHODS

A retrospective analysis of patients who underwent SLN mapping as part of their primary surgery for endometrial cancer. Patients underwent preoperative PLSG and later with additional SPECT/CT. Intraoperative detection was performed using TC99m colloid and blue dye by cervical injections. SLNs were sent separately for pathologic evaluation with ultrastaging.

RESULTS

Fifty-three patients were included in this study. Successful preoperative mapping was achieved in 31 of 37 patients (84 %) who underwent SPECT/CT compared with only 30 of 45 patients (67 %) who underwent PLSG. SPECT/CT localizations of SLNs were anatomically accurate in 91 % of cases. Intraoperative DR of at least one SLN was 77 %, whilst the bilateral DR was 49 %. DR was significantly better using combined blue dye and TC99m colloid injections compared with blue dye alone: 81 versus 57 % for unilateral and 54 versus 28 % for bilateral mapping (P = 0.01, 0.009, respectively). Six cases of nodal metastasis were diagnosed: four by positive SLNs, and two cases were diagnosed using side-specific full dissection according to the SLN algorithm when SLN detection failed. There were no cases of false-negative results.

CONCLUSIONS

SLN detection using cervical injections of TC99m colloid and blue dye is feasible and sensitive for patients with endometrial cancer. SPECT/CT aids to accurate locating of the SLN.

Laparoscopic Sentinel Node Biopsy Using Real-time 3-dimensional Single-photon Emission Computed Tomographic Guidance in Endometrial Cancer

In endometrial cancer, the histopathological analysis of the lymphatic nodes is essential to establish a correct prognosis and tailored adjuvant treatment. It is well-known that patients with early-stage endometrial cancer have a low incidence of nodal disease. In this group, systematic lymphadenectomy is not recommended. To improve the detection rate of sentinel nodes in clinical practice, new techniques are emerging like real-time 3-dimensional single-photon emission computed tomographic (SPECT) imaging. We report our experience using this innovative technique for intraoperative detection of sentinel nodes in endometrial cancer. The real-time 3-dimensional SPECT sentinel node biopsy seems to be feasible and accurate in endometrial cancer although further studies are needed to set the precision and predictive values compared with the current differed SPECT techniques and blue dye techniques.

99mTc SPECT/CT Versus Planar Lymphoscintigraphy for Preoperative Sentinel Lymph Node Detection in Cervical Cancer: A Systematic Review and Metaanalysis

We aimed to compare SPECT/CT and lymphoscintigraphy on overall and bilateral sentinel lymph node (SLN) detection in cervical cancer patients.

METHODS

A systematic search was performed on August 1, 2014, in PubMed, Embase, Scopus, and the Cochrane library. The syntax was based on synonyms of the terms cervical cancer, SPECT/CT, and lymphoscintigraphy. Retrieved articles were screened on their title/abstract and considered eligible when an SLN procedure was performed using both imaging modalities and if detection results were reported. Two independent reviewers assessed all included studies on methodologic quality using QUADAS-2. Studies were pooled on their odds ratios (ORs) with a random-effects model.

RESULTS

The search yielded 962 unique articles, of which 8 were ultimately included. The studies were recent retrospective or prospective cohort studies of limited size (n = 7-51) but sufficient methodologic quality. The median overall detection (≥1 SLN in a patient) was 98.6% for SPECT/CT (range, 92.2%-100.0%) and 85.3% for lymphoscintigraphy (range, 70.0%-100.0%). This corresponded to a pooled overall SLN detection OR of 2.5 (95% CI, 1.2-5.3) in favor of SPECT/CT. The reported median bilateral detection (≥1 SLN in each hemipelvis) was 69.0% for SPECT/CT (range, 62.7%-79.3%) and 66.7% for lymphoscintigraphy (range, 56.9%-75.8%), yielding a pooled OR of 1.2 (95% CI, 0.7-2.1). No significant difference in the number of visualized SLNs was observed at a pooled ratio of 1.2 (95% CI, 0.9-1.6).

CONCLUSION

In cervical cancer patients, preoperative SLN imaging with SPECT/CT results in superior overall SLN detection in comparison with planar lymphoscintigraphy.

Sentinel-lymph-node procedures in early stage cervical cancer: a systematic review and meta-analysis

We performed a meta-analysis to assess the accuracy of sentinel-lymph-node (SLN) procedures for the assessment of nodal metastases in patients with early stage cervical cancer. Studies of SLN procedures for detecting nodal metastases in patients with early stage cervical cancer were systematically searched in MEDLINE and EMBASE between January 1, 2000 and August 30, 2013. We identified 49 eligible studies, which included 2,476 SLN procedures. The mean overall weighted-detection rate was 0.93 (95 % CI 0.92–0.94), at a pooled sensitivity of 0.88 (95 % CI 0.84–0.90) with limited heterogeneity (χ² = 80.57, degrees of freedom = 47, p = 0.002). Subgroup analysis of sensitivity and the rate of detection of different tracer techniques and surgery methods used in conjunction with an SLN procedures were as follows: studies using combined techniques, 0.88 (95 % CI 0.84–0.91) and 0.97 (95 % CI 0.96–0.98); studies using metastable technetium-99, 0.87 (95 % CI 0.78–0.93) and 0.90 (95 % CI 0.87–0.93); studies using blue dye, 0.87 (95 % CI 0.79–0.93) and 0.87 (95 % CI 0.84–0.90); studies using laparotomy, 0.86 (95 % CI 0.80–0.90) and 0.87 (95 % CI 0.83–0.91); studies using laparoscopy, 0.90 (95 % CI 0.86–0.94) and 0.93 (95 % CI 0.90–0.96); and studies using robot-assisted surgery, 0.84 (95 % CI 0.72–0.92) and 0.92 (95 % CI 0.88–0.95). We concluded that the SLN procedure performs well diagnostically for the assessment of nodal metastases in patients with early stage cervical cancer.

Sentinel node biopsy for lymph nodal staging of uterine cervix cancer: a systematic review and meta-analysis of the pertinent literature

BACKGROUND

We reviewed the available literature on the accuracy of sentinel node mapping in the lymph nodal staging of uterine cervical cancers.

METHODS

MEDLINE and Scopus were searched by using "sentinel AND (cervix OR cervical)" as key words. Studies evaluating the accuracy of sentinel node mapping in the lymph nodal staging of uterine cervical cancers were included if enough data could be extracted for calculation of detection rate and/or sensitivity.

RESULTS

Sixty-seven studies were included in the systematic review. Pooled detection rate was 89.2% [95% CI: 86.3-91.6]. Pooled sensitivity was 90% [95% CI: 88-92]. Sentinel node detection rate and sensitivity were related to mapping method (blue dye, radiotracer, or both) and history of pre-operative neoadjuvant chemotherapy. Sensitivity was higher in patients with bilaterally detected pelvic sentinel nodes compared to those with unilateral sentinel nodes. Lymphatic mapping could identify sentinel nodes outside the routine lymphadenectomy limits.

CONCLUSION

Sentinel node mapping is an accurate method for the assessment of lymph nodal involvement in uterine cervical cancers. Selection of a population with small tumor size and lower stage will ensure the lowest false negative rate. Lymphatic mapping can also detect sentinel nodes outside of routine lymphadenectomy areas providing additional histological information which can improve the staging. Further studies are needed to explore the impact of sentinel node mapping in fertility sparing surgery and in patients with history of neoadjuvant chemotherapy.

Value and advantages of preoperative sentinel lymph node imaging with SPECT/CT in cervical cancer

OBJECTIVE

Precise detection of sentinel lymph nodes (SLNs) seems to be a crucial factor for optimized treatment of cervical cancer. We assess the use of single photon emission computed tomography combined with computed tomography (SPECT/CT) as an alternative to lymphoscintigraphy (LSG) for preoperative identification of SLN.

METHODS

This study was performed in a prospective, unicentric setting. Patients with cervical carcinoma were scheduled for surgery and additional SLN labeling by peritumoral injection of 10 MBq technetium-99m-nanocolloid and patent blue. Thirty minutes after injection, LSG and SPECT/CT were carried out. We evaluated the number of SLNs detected intraoperatively in LSG and SPECT/CT and the histologic findings of SLN and non-SLN. Subsequently, we determined the impact of these results on the therapeutic approach.

RESULTS

This represents the largest study about SPECT/CT for SLN detection in cervical cancer so far. Between August 2008 and March 2013, 59 cervical cancer patients underwent intraoperative SLN detection. In addition, 51 of these patients underwent preoperative LSG and SPECT/CT. Imaging with SPECT/CT detected singular SLN at significantly higher rate (47/51, 92.2%) than that with planar LSG (43/51, 84.3%, P = 0.044). Furthermore, SPECT/CT performed better than LSG regarding the total number of detected SLN (SPECT/CT median, 3 [0-18]; LSG median, 2 [0-15]) and detection rates per pelvic side (SPECT/CT 76.9%, LSG 69.2%, P < 0.01). Whenever SLN detection succeeded, histologic evaluation of SLN correctly predicted the lymph node status per patient's side. Using this type of diagnostic approach for lymph node staging, we reached sensitivity of 100% and negative predictive value of 100% at a rate of false-negative results of 0% even in tumors larger than 4 cm.

CONCLUSIONS

Single photon emission computed tomography combined with computed tomography imaging leads to improved rates of SLN detection and better anatomic correlation compared with planar LSG. Thus, intraoperative detection of SLN can be improved by preoperative SPECT/CT imaging. This enhances the clinical value of SLN technique and improves the oncologic safety of SLN concept.

[Sentinel lymph node in low stage cervical cancers. Current data. Quality assurance. Prospects]

Sentinel node biopsy appears as a promising technique for the assessment of nodal disease in early cervical cancers. Selection of a population with a low risk of nodal metastasis, a minimal training, and simple rules allow a low false negative rate. Sentinel node biopsy provides supplementary information, such as anatomical information (nodes outside of routine lymphadenectomy areas) and histological information (isolated tumors cells and micrometastases).

Sentinel lymph node evaluation in women with cervical cancer

Lymph node status is the most important prognosticator of survival in women with early stage cervical cancer. Thus many patients with cervical cancer will undergo pelvic lymphadenectomy as part of the treatment. This procedure is associated with substantial morbidity. Use of the sentinel lymph node technique in women with cervical cancer has the potential to decrease this morbidity. Multiple studies have suggested that sentinel lymph node mapping in these patients is feasible, with excellent detection rates and sensitivity. This review examines the current body of literature about sentinel lymph node biopsy in women with cervical cancer.

Pelvic kidney visualization on the lymphoscintigraphy images of a patient with uterine cervix cancer: importance of the delayed imaging

We reported an unusual visualization of a pelvic kidney on the lymphoscintigraphy images of a patient with uterine cervix cancer, which was mistaken with para-aortic sentinel nodes. Delayed imaging clearly showed the nature of this activity. Our case underscores the importance of delayed pelvic lymphoscintigraphy imaging in the sentinel node mapping of gynecological cancers.