The efficacy of sentinel lymph node mapping with indocyanine green in cervical cancer

Comparative study using indocyanine green and patent blue dye for sentinel lymph node biopsy in patients with early-stage cervical cancer

BACKGROUND

Lymphatic involvement is the most important prognostic factor in early-stage cervical cancer. Sentinel lymph node biopsy is a viable alternative to systematic lymphadenectomy and may identify metastases more precisely.

OBJECTIVE

To compare two tracers (indocyanine green and patent blue) to detect sentinel nodes.

METHODS

A single-center, retrospective study of women treated due to early-stage cervical cancer (International Federation of Gynecology and Obstetrics 2009 IA1 with lymphovascular invasion, IA2, and IB1). Location and tracer of all detected sentinel nodes had been documented for a prospective, multicenter trial (SENTIX trial). All sentinel nodes were sent to frozen section and final analysis through ultrastaging using a standard protocol.

RESULTS

Overall, 103 patients were included. Bilateral detection rate for indocyanine green (93.2%) was significantly higher than for blue dye (77.7%; p=0.004). Their combined use significantly increased the bilateral detection to 99.0% (p=0.031). While 97.4% of all sentinel nodes were located below the common iliac vessels, no para-aortic nodes were labeled. Simultaneous bilateral detection with both tracers was found in 71.8% of the cases, of which the sentinel nodes were identical in 91.9%. Nine positive nodes were detected among seven patients (6.8%), all marked with indocyanine green while patent blue labeled six. Frozen section failed to detect one of three macrometastases and three of four micrometastases (sensitivity 43%; negative prediction value 96%).

CONCLUSION

Anatomical distribution and topographic localization of the sentinel nodes obtained with these tracers were not different. Indocyanine green provided a significantly higher bilateral detection rate and had superior sensitivity to detect positive nodes compared with patent blue. Combining indocyanine green and blue dye increased the bilateral detection rate significantly.

Feasibility of Sentinel Lymph Node Mapping With Carbon Nanoparticles in Cervical Cancer: A Retrospective Study

INTRODUCTION

This retrospective study aims to investigate the feasibility of using carbon nanoparticles to detect sentinel lymph nodes (SLNs) in cervical cancer.

METHODS

This study involved 174 patients with cervical cancer. Cervix tissues adjacent to the cancer were injected with 1 mL of carbon nanoparticles (CNPs) at the 3 and 9 o'clock positions according to the instructions. The pelvic lymph nodes were then dissected, and the black-stained sentinel lymph nodes were sectioned for pathological examination.

RESULTS

Of 174 cases, 88.5% of patients (154/174) had at least 1 sentinel lymph node, and 131 patients (75.29%) had bilateral pelvic sentinel lymph nodes. The left pelvic lymph node was the most common sentinel lymph node (34.16%). At least 1 sentinel lymph node was observed in 285 out of 348 hemipelvises, with a detection rate of a side-specific sentinel lymph node of 81.89%. In total, 47 hemipelvises had metastasis of the lymph node, and 33 involved the sentinel lymph node, with a sensitivity of 70.21% and a false-negative rate of 29.79%. There were 238 hemipelvises with no metastasis of the lymph node, as well as negative sentinel lymph nodes, with a specificity of 100% and a negative predictive value of 94.44%. The univariate analysis demonstrated that risk factors included tumor size (OR .598, 95% CI: .369-.970) and deep stromal invasion (OR .381, 95% CI: .187-.779). The deep stromal invasion was the only variable for the false-negative detection of a sentinel lymph node.

CONCLUSION

Sentinel lymph node mapping with carbon nanoparticles might be applied to predict the metastasis of pelvic lymph nodes in cervical cancer. However, tumor size and deep stromal invasion might negative influence the detection rate of SLN.

[Carbon nanoparticle tracing of sentinel lymph nodes in diagnosis and treatment of cervical cancer and clinical value of lymph node ultrastaging detection]

OBJECTIVE

To evaluate the clinical value of sentinel lymph node (SLN) detection using carbon nanoparticles in the diagnosis and treatment of cervical cancer and the value of lymph node pathological ultrastaging detection.

METHODS

A total of 79 patients with cervical cancer in IA2, IB1, IB2, IIA1 and IIICp1 stages admitted to the Department of Gynecology and Obstetrics, Nanfang Hospital between June, 2018 and January, 2021 were included in this study. During the operation, the patients were injected with a total of 0.25 mL carbon nanoparticles at 3 and 9 o'clock of the normal cervix after general anesthesia. The first black-dyed lymph nodes were identified as SLNs and removed one by one. All the patients underwent pelvic lymph node dissection and radical hysterectomy with or without para-aortic lymphadenectomy. The black-dyed SLNs were removed for routine pathological examination. Thirty patients with negative SLNs were randomly selected for pathological ultrastaging.

RESULTS

In 67 of the 79 patients, a total of 417 SLNs were detected with a detection rate of 84.8%; in each patient, at least 1 SLN was detected with a mean SLN number of 5.28. After the operation, 5 patients were found to have positive SLNs; 1 patient was negative for SLN but positive for non-SLN. The sensitivity of SLN biopsy was 83.3% with a specificity of 100%, false negative rate of 16.7%, an accuracy of 98.5% and a negative predictive value of 98.4%. SLN was distributed mainly in the obturator region, the external iliac region, the internal iliac region and the total iliac region (15.11%). Univariate and multivariate analyses suggested that preoperative cervical coning (P=0.045 and 0.009) and tumor size (P=0.033 and 0.008) significantly affected the overall detection rate of SLN. Kappa test showed a high consistency between SLN and pelvic lymph node metastasis status (Kappa value=0.901, P < 0.001). In 30 patients with negative pathological results of SLN, pathological ultrastaging detection identified no micrometastases or isolated tumor cells.

CONCLUSION

Carbon nanoparticle tracing of the SLNs is safe and feasible in the diagnosis and treatment of cervical cancer, and SLN detection is safe in patients with primary lesion size below 2 cm or without cervical conization. SLN combined with pathological ultrastaging detection does not improve the detection rate of isolated tumor cells or micrometastases.

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.

Indocyanine green-guided sentinel lymph node mapping during laparoscopic surgery with vaginal cuff closure but no uterine manipulator for cervical cancer

BACKGROUND

Lymph node metastasis is a critical prognostic factor in cervical cancer. Considering the potential complications of lymphadenectomy and desirability of avoiding systemic lymphadenectomy, accurate intraoperative prediction of the existence of lymph node metastasis is important in patients undergoing surgery for cervical cancer. We evaluated the feasibility and value of indocyanine green (ICG) use for sentinel lymph node (SLN) mapping during laparoscopic surgery performed for cervical cancer.

METHODS

This single-center cohort study included 77 patients undergoing a new laparoscopic radical surgery method with pelvic lymphadenectomy for early-stage cervical cancer. The surgery, performed without using a uterine manipulator, included creation of a vaginal cuff. Bilateral ICG-guided SLN mapping and rapid histopathological examination were performed, and results were analyzed in relation to final histopathologic diagnoses.

RESULTS

The SLN pelvic side-specific detection rate was 93.5%, sensitivity (SLN-positive cases/SLN-detected pelvic lymph node-positive cases) was 100%, intraoperative negative predictive value (NPV) was 97.8%, and final pathological NPV was 100%. The detection rate was significantly lower for tumors ≥ 2 cm in diameter than for tumors < 2 cm in diameter. Micrometastases were missed by intraoperative examination in 3 cases.

CONCLUSION

The high NPV suggests the feasibility and usefulness of ICG-based SLN mapping plus rapid intraoperative examination for identification of metastatic SLNs. Use of ICG-based mapping for intraoperative identification of SLNs in patients undergoing this new laparoscopic surgery method for early-stage cervical cancer was particularly effective for tumors < 2 cm in diameter. However, incorporating a search for micrometastases into rapid intraoperative histopathologic examination may be necessary.

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.

Identification and Biopsy of Sentinel Lymph Node in Early-Stage Cervical Carcinoma: Diagnostic Accuracy and Clinical Utility

Background Due to the subsequent complications of pelvic lymphadenectomy in patients with early-stage cervical cancer, the sentinel lymph node (SLN) technique has been increasingly employed. This study aimed to investigate the detectability of SLN using methylene blue and explore the diagnostic accuracy of SLN biopsy. Methodology A study was conducted from September 2015 to August 2018 and included 90 women with cervical cancer, FIGO (International Federation of Gynecology and Obstetrics-2009) stage IA1-IIA1. Methylene blue was injected intracervically. Any detected dyed nodes were sent for frozen section biopsy, followed by bilateral pelvic lymphadenectomy. The predictive ability of SLN was evaluated in statistical terms after comparison of intraoperative biopsy and final histopathology. Results The sensitivity, specificity, false-negative rate, positive predictive value, and negative predictive value (NPV) were 55.6%, 95.1%, 4.9%, 55.6%, and 95.1%, respectively. The SLN performance in patients with tumor size ≤2.2 cm, negative lymphovascular space involvement, and depth of stromal invasion ≤5 mm was superior (sensitivity 100%, specificity 93.5%, NPV 100%). Conclusions The SLN technique with blue dye alone is a feasible and adequate alternative to systematic lymphadenectomy in early-stage cervical cancer in selected patients, given that a strict algorithm is applied.

A Review of Nuclear Medicine Approaches in the Diagnosis and the Treatment of Gynecological Malignancies

Nuclear medicine is defined as the diagnosis and the treatment of disease using radiolabeled compounds known as radiopharmaceuticals. Single-photon emission computed tomography/computed tomography (SPECT/CT) and positron emission tomography/computer tomography (PET/CT) based radiopharmaceuticals have proven reliable in diagnostic imaging in nuclear medicine and cancer treatment. One of the most critical cancers that also relies on an early diagnosis is gynecological cancer. Given that approximately 25% of all cancers in developing countries are a subset of gynecological cancer, investigating this cancer subtype is of significant clinical worth, particularly in light of its high rate of mortality. With accurate identification of high grade distant abdominal endometrial cancer as well as extra abdominal metastases, 18F-Fluorodeoxyglucose ([18F]FDG) PET/CT imaging is considered a valuable step forward in the investigation of gynecological cancer. Considering these factors, [18F]FDG PET/CT imaging can assist in making management of patient therapy more feasible. In this literature review, we will provide a short overview of the role of nuclear medicine in the diagnosis of obstetric and gynecological cancers.

Clinical Study of Sentinel Lymph Node Detection to Evaluate Pelvic Lymph Node Metastasis to Determine the Prognosis of Patients with Early Cervical Cancer

Objective

Lymph node status is one of the most important prognostic factors for uterine cervical cancer. Sentinel lymph node (SLN) biopsy has emerged as a potential alternative to systematic lymphadenectomy for the lymph node mapping in such patients. However, the SLN metastasis detection via SLN biopsy in early-stage cervical cancer remains controversial. The current study is aimed at investigating the feasibility and accuracy of combined tracer method for localization of SLN in initial stages of cervical cancer and to evaluate the clinical value of SLN biopsy in replacing pelvic lymph node resection.

Methods

We retrospectively reviewed 348 cases who were admitted to the Department of Gynecologic Oncology, Shandong Provincial Cancer Hospital, China, between February 2003 and June 2018 with FIGO stage IA2 to IIA2 cervical cancer and undergone through SLN biopsy. Methylthioninium chloride was injected in combination with ^99mtechnetium-labeled sulfur colloid prior to surgery to these patients. SLNs were identified intraoperatively, excised, and subsequently submitted to fast frozen section. The detection rates, accuracy, sensitivity, coincidence rate, false negative rate, and negative predictive values of these cases were estimated, and the follow-up outcomes were carefully observed. Chi squared test or Fisher's exact test was employed for a comparison of the categorical variables. Univariate and multivariate Cox proportional hazard models were used for estimation of relationships between overall survival (OS) and disease-free survival (DFS) and prognostic factors.

Results

The total detection rate of SLN was 97.1% (338/348), and identification of bilateral SLN was successful in 237 patients (70.1%). The patient's tumor size, FIGO stage, lymph node metastasis, and depth of invasion had statistically significant differences in SLN detection rates. The detection rate had inverse relation with tumors size (>4 cm), invasive depth > 2/3, lymph node positive, late staging, and preoperative radiotherapy. 117 positive SLNs were detected in 73 patients. The negative predictive value, sensitivity, false negative rate, and coincidence rate and were 97.7%, 92.4%, 7.6%, and 95.4%, respectively. In patients whose tumor size were ≦ 4 cm, the false negative rate was 4.55% (2/44), whereas it was 0 in patients with tumor size≦2 cm. The respective 1, 3, and 5-year OS was 100%, 94.8%, and 91.8%, respectively, whereas DFS rate for 1, 3, and 5 years was 96.7%, 92%, and 89.6%, respectively. The lymph node was positive, tumor size, the depth of invasion, and staging were statistically different from the recurrence rate and survival rate of patients (p < 0.05). When tumor metastasis exceeded SLN, the recurrence rate was significantly increased, and survival rate is significantly reduced (p < 0.05, p < 0.01, p < 0.05, respectively).

Conclusions

The identification of SLN combined with ^99mtechnetium-labeled sulfur colloid and methylthioninium chloride has a good accuracy and is safe for the assessment of the status of pelvic nodes in patients with initial stage cervical cancer. Nuclide as a tracer has low dependence on objective conditions and doctors' technology and has a good detection rate. In our study, we believe that SLN biopsy is feasible when the tumor is ≦ 4 cm. Large scale clinical trials are required in China expand the sample size and validate the results of this study.

Transvaginal lymphatic embolization of the fistula between a pelvic lymphocele and the vaginal stump following radical hysterectomy and sentinel pelvic lymph node biopsy in a patient with cervical cancer: A case report

A lymphocele is a common complication that occurs following pelvic lymph node dissection. However, the complication of lymphoceles following sentinel pelvic lymph node biopsy has not been previously reported, to the best of our knowledge. A 49-year-old female patient had undergone radical hysterectomy and pelvic lymph node biopsy for stage IB1 cervical cancer 5 months previously and presented with a profuse watery vaginal discharge of ~2 liters per day. A fistula connecting the lymphocele and the vaginal stump was identified using lymphoscintigraphy and single photon emission CT/CT. Transvaginal lymphatic embolization was successfully performed through the vaginal fistulous tract, resulting in immediate reduction of the vaginal discharge. In conclusion, the case of fistula formation between pelvic lymphocele and vaginal stump was encountered at our department and was reported with a literature review. To the best of our knowledge, there are no previous reports on lymphoceles with direct communication to the vaginal mucosa, particularly following sentinel pelvic lymph node biopsy. The present study reported the case of a patient who was successfully treated for a pelvic lymphocele with direct communication to the vaginal mucosa.

Sentinel lymph node detection by combining nonradioactive techniques with contrast agents: State of the art and prospects

The status of sentinel lymph nodes (SLNs) has a substantial prognostic value because these nodes are the first place where cancer cells accumulate along their spreading route. Routine SLN biopsy ("gold standard") involves peritumoral injections of radiopharmaceuticals, such as technetium-99m, which has obvious disadvantages. This review examines the methods used as "gold standard" analogs to diagnose SLNs. Nonradioactive preoperative and intraoperative methods of SLN detection are analyzed. Promising photonic tools for SLNs detection are reviewed, including NIR-I/NIR-II fluorescence imaging, photoswitching dyes for SLN detection, in vivo photoacoustic detection, imaging and biopsy of SLNs. Also are discussed methods of SLN detection by magnetic resonance imaging, ultrasonic imaging systems including as combined with photoacoustic imaging, and methods based on the magnetometer-aided detection of superparamagnetic nanoparticles. The advantages and disadvantages of nonradioactive SLN-detection methods are shown. The review concludes with prospects for the use of conservative diagnostic methods in combination with photonic tools.

Sentinel Lymph Node Staging with Indocyanine Green for Patients with Cervical Cancer: The Safety and Feasibility of Open Approach Using SPY-PHI Technique

Simple Summary

While several studies have been conducted on the safety and efficacy of sentinel lymph node technique during minimally invasive radical hysterectomy and indicated that using indocyanine green alone is a better tracer agent, there is now high unmet medical need and growing demand for more data about sentinel lymph node detection and the most suitable tracer in open surgery for cervical cancer, especially after the publishing of the of Laparoscopic Approach to Cervical Cancer (LACC) Trial data. The aim of this study is to assess the feasibility and safety of sentinel lymph nodes with indocyanine green in cervical cancer patients undergoing radical hysterectomy in open surgery and to compare the detection rates of this tracer in the open versus laparoscopic approaches.

Abstract

(1) Background: Sentinel lymph node staging (SLN) with indocyanine green (ICG) in cervical cancer is the standard of care in most national and international guidelines. However, the vast majority of relevant studies about the safety and feasibility of this method are conducted on minimally invasive surgery; (2) Methods: This study is a retrospective analysis of a retrospective collected database of 76 consecutive patients with cervical cancers, who were operated laparoscopically (50%), or laparotomy (50%). Sentinel nodes were defined as the ICG-positive pelvic nodes in the first and second echelons. False negative cases were defined as positive non-sentinel lymph nodes despite successful sentinel mapping or failed mapping bilaterally by per-patient assessment or unilaterally by pelvic sidewall assessment; (3) Results: Regardless of the approach (open or laparoscopic), the SLN technique achieved a total sensitivity, specificity, and negative predictive value (NPV) of 94.7%, 98.6%, and 94.7%, respectively in the entire sample. The bilateral detection rate was as high as 93.4% with identical results in both approaches. The sensitivity and NPV for SNL in open surgery was found to be similar to minimal access surgery; (4) Conclusions: ICG and SPY-PHI technique is a reliable tool to detect sentinel lymph nodes in cervical cancer during laparotomy.

Sentinel lymph node mapping in early-stage cervical cancer: Meta-analysis

BACKGROUND

The value of sentinel lymph node (SLN) mapping for early-stage cervical cancer remains controversial. Therefore, we collected data to investigate the feasibility and diagnostic accuracy of SLN in patients with early-stage (IA-IIA) cervical cancer.

METHODS

We searched Embase, PubMed, and the Cochrane Library databases issued before June 1, 2020. The sample size of the selected study was at least 10 patients with early-stage (IA-IIA) cervical cancer, the pooled detection rates and the separate detection rate (overall detection rate, bilateral detection rate) using blue dye with Tc, technetium 99 (Tc) and indocyanine green (ICG) technique of early-stage cervical cancer was reported. R-3.6.1 software was used to evaluate pooled detection rate and sensitivity.

RESULTS

Two thousand one hundred sixty-four patients included for analysis in 28 studies ranging from 12 to 405 patients. The combined overall detection rate of SLN mapping was 95% with a 72% pooled bilateral detection rate. The sensitivity of the combined overall detection rate of SLN mapping was 94.99% as well as a sensitivity of 72.43% bilateral detection rate. The overall detection rate of SLN was 96% for blue dye with Tc, 95% for Tc, 98% for ICG technique. The bilateral detection rate of SLN was 76% for blue dye with Tc, 63% for Tc, 85% for ICG technique. The sensitivity of the overall detection rate of SLN mapping was 97.76% as well as a sensitivity of 84.96% bilateral detection rate of ICG technique.

CONCLUSION

In early-stage cervical cancer, overall detection rate of SLN mapping is elevated while bilateral detection rate is lower. The overall detection rate (98%) as well as bilateral rate (85%) of ICG seems to be a better SLN mapping technique among the method of SLN mapping (using blue dye with Tc, Tc or ICG). We believe SLN mapping may be considered contemporary technique which could provide additional benefits over traditional pelvic lymphadenectomy. While promising results in SLN mapping has been found, larger patient samples, including randomized studies, are required at the same time.

Sentinel node biopsy for diagnosis of lymph node involvement in endometrial cancer

BACKGROUND

Pelvic lymphadenectomy provides prognostic information for those diagnosed with endometrial (womb) cancer and provides information that may influence decisions regarding adjuvant treatment. However, studies have not shown a therapeutic benefit, and lymphadenectomy causes significant morbidity. The technique of sentinel lymph node biopsy (SLNB), allows the first draining node from a cancer to be identified and examined histologically for involvement with cancer cells. SLNB is commonly used in other cancers, including breast and vulval cancer. Different tracers, including colloid labelled with radioactive technetium-99, blue dyes, e.g. patent or methylene blue, and near infra-red fluorescent dyes, e.g. indocyanine green (ICG), have been used singly or in combination for detection of sentinel lymph nodes (SLN).

OBJECTIVES

To assess the diagnostic accuracy of sentinel lymph node biopsy (SLNB) in the identification of pelvic lymph node involvement in women with endometrial cancer, presumed to be at an early stage prior to surgery, including consideration of the detection rate.

SEARCH METHODS

We searched MEDLINE (1946 to July 2019), Embase (1974 to July 2019) and the relevant Cochrane trial registers.

SELECTION CRITERIA

We included studies that evaluated the diagnostic accuracy of tracers for SLN assessment (involving the identification of a SLN plus histological examination) against a reference standard of histological examination of removed pelvic +/- para-aortic lymph nodes following systematic pelvic +/- para-aortic lymphadenectomy (PLND/PPALND) in women with endometrial cancer, where there were sufficient data for the construction of two-by-two tables.

DATA COLLECTION AND ANALYSIS

Two review authors (a combination of HN, JM, NW, RG, and WH) independently screened titles and abstracts for relevance, classified studies for inclusion/exclusion and extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We calculated the detection rate as the arithmetic mean of the total number of SLNs detected out of the total number of women included in the included studies with the woman as the unit of analysis, used univariate meta-analytical methods to estimate pooled sensitivity estimates, and summarised the results using GRADE.

MAIN RESULTS

The search revealed 6259 unique records after removal of duplicates. After screening 232 studies in full text, we found 73 potentially includable records (for 52 studies), although we were only able to extract 2x2 table data for 33 studies, including 2237 women (46 records) for inclusion in the review, despite writing to trial authors for additional information. We found 11 studies that analysed results for blue dye alone, four studies for technetium-99m alone, 12 studies that used a combination of blue dye and technetium-99m, nine studies that used indocyanine green (ICG) and near infra-red immunofluorescence, and one study that used a combination of ICG and technetium-99m. Overall, the methodological reporting in most of the studies was poor, which resulted in a very large proportion of 'unclear risk of bias' ratings. Overall, the mean SLN detection rate was 86.9% (95% CI 82.9% to 90.8%; 2237 women; 33 studies; moderate-certainty evidence). In studies that reported bilateral detection the mean rate was 65.4% (95% CI 57.8% to 73.0%) . When considered according to which tracer was used, the SLN detection rate ranged from 77.8% (95% CI 70.0% to 85.6%) for blue dye alone (559 women; 11 studies; low-certainty evidence) to 100% for ICG and technetium-99m (32 women; 1 study; very low-certainty evidence). The rates of positive lymph nodes ranged from 5.2% to 34.4% with a mean of 20.1% (95% CI 17.7% to 22.3%). The pooled sensitivity of SLNB was 91.8% (95% CI 86.5% to 95.1%; total 2237 women, of whom 409 had SLN involvement; moderate-certainty evidence). The sensitivity for of SLNB for the different tracers were: blue dye alone 95.2% (95% CI 77.2% to 99.2%; 559 women; 11 studies; low-certainty evidence); Technetium-99m alone 90.5% (95% CI 67.7% to 97.7%; 257 women; 4 studies; low-certainty evidence); technetium-99m and blue dye 91.9% (95% CI 74.4% to 97.8%; 548 women; 12 studies; low-certainty evidence); ICG alone 92.5% (95% CI 81.8% to 97.1%; 953 women; 9 studies; moderate-certainty evidence); ICG and blue dye 90.5% (95% CI 63.2.6% to 98.1%; 215 women; 2 studies; low-certainty evidence); and ICG and technetium-99m 100% (95% CI 63% to 100%; 32 women; 1 study; very low-certainty evidence). Meta-regression analyses found that the sensitivities did not differ between the different tracers used, between studies with a majority of women with FIGO stage 1A versus 1B or above; between studies assessing the pelvic lymph node basin alone versus the pelvic and para-aortic lymph node basin; or between studies that used subserosal alone versus subserosal and cervical injection. It should be noted that a false-positive result cannot occur, as the histological examination of the SLN is unchanged by the results from any additional nodes removed at systematic lymphadenectomy.

AUTHORS' CONCLUSIONS

The diagnostic test accuracy for SLNB using either ICG alone or a combination of a dye (blue or ICG) and technetium-99m is probably good, with high sensitivity, where a SLN could be detected. Detection rates with ICG or a combination of dye (ICG or blue) and technetium-99m may be higher. The value of a SLNB approach in a treatment pathway, over adjuvant treatment decisions based on uterine factors and molecular profiling, requires examination in a high-quality intervention study.

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.

Use of a Novel Fluorescent Catheter to Locate the Ureters during Total Laparoscopic Hysterectomy

Ureteral injury can occur during total laparoscopic hysterectomy. This report documents our experience in using the near-infrared ray catheter (NIRC), a newly developed fluorescent ureteral catheter made of material that contains a fluorescent dye to improve visualization of the ureters. We have used the device in 3 patients between 40 and 50 years of age (mean, 46.3 ± 4.5 years) undergoing total laparoscopic hysterectomy and bilateral salpingectomy for uterine myomas. The time of catheter insertion ranged from 4 minutes and 9 seconds to 10 minutes and 57 seconds. A number of intraoperative procedures were performed near the ureters, namely, identification and ligation of the uterine arteries, dissection of the cardinal ligament, incision of the vaginal canal, and suturing of the vaginal stump. The abovementioned fluorescent ureteral catheter appears green on a monitor when illuminated by near-infrared light, and this facilitated real-time confirmation of the ureter positions, increasing surgical safety. The patients were followed up for 6 months postoperatively, and no urinary tract infection or injury was found. Prophylactic use of the fluorescent ureteral catheter may improve visualization of the ureters in patients considered to be at high risk of ureteral injury, such as those expected to exhibit ureteral deviation due to severe adhesions or an enlarged uterus and when the surgeon has little experience in laparoscopic surgery.

Feasibility of T2WI-MRI-based radiomics nomogram for predicting normal-sized pelvic lymph node metastasis in cervical cancer patients

OBJECTIVE

To investigate the feasibility of T₂WI-based radiomics nomogram analysis to non-invasively predict normal-sized pelvic lymph node (LN) metastasis (LNM) in cervical cancer patients.

METHODS

Preoperative images of 219 normal-sized pathologically confirmed LNs from 132 cervical cancer patients admitted to our hospital between January 2013 and March 2020 were retrospectively reviewed. Regions of interests (ROIs) were separately delineated on whole LNs and tumors. The maximum-relevance and minimum-redundancy (mRMR) and least absolute shrinkage and selection operator (LASSO) methods were used for the construction of radiomics signature. Logistic regression modeling was employed to build models based on clinical features on LN T₂WI (model 1), model 1 combined with LN radiomics features (model 2), and model 2 combined with tumor score (model 3). Diagnostic performance was assessed and compared.

RESULTS

Both model 2 and model 3 showed higher diagnostic accuracy (training: model 2 0.75, model 3 0.78, model 1 0.72; validation: model 2 0.77, model 3 0.69, model 1 0.66) and AUC (training: model 2 0.77, model 3 0.82, model 1 0.74; validation: model 2 0.75, model 3 0.74, model 1 0.70) than clinical model 1. Diagnostic performance of model 3 was improved compared with model 2 in primary cohort, but reduced in validation cohort. However, the differences did not show obvious statistical difference (p = 0.05 and p = 0.15).

CONCLUSIONS

T₂WI-based radiomics nomogram incorporating the LN radiomics signature with the clinical morphological LN features is promising for predicting the normal-sized pelvic LNM in cervical cancer patients. The original tumor radiomics analysis did not significantly improve the differential diagnosis of LNM.

KEY POINTS

• The combination of LN radiomics signature with LN clinical morphological features on T₂WI could discriminate LNM relatively well. • The tumor radiomics analysis did not significantly improve the differential diagnosis of LNM.

Utility of Intraoperative Fluorescence Imaging in Gynecologic Surgery: Systematic Review and Consensus Statement

BACKGROUND

This study aimed to review the current knowledge on the utility of intraoperative fluorescence imaging in gynecologic surgery and to give evidence-based recommendations to improve the quality of care for women who undergo gynecologic surgery.

METHODS

A computer-based systematic review of the MEDLINE, CENTRAL, Pubmed, EMBASE, and SciSearch databases as well as institutional guidelines was performed. The time limit was set at 2000-2019. For the literature search, PRISMA guidelines were followed. A modified-Delphi method was performed in three rounds by a panel of experts to reach a consensus of conclusions and recommendations.

RESULTS

Indocyanine green (ICG) is used primarily in gynecology for sentinel node-mapping. In endometrial and cervical cancer, ICG is a feasible, safe, time-efficient, and reliable method for lymphatic mapping, with better bilateral detection rates. Experience in vulvar cancer is more limited, with ICG used together with Tc-99 m as a dual tracer and alone in video endoscopic inguinal lymphadenectomy. In early ovarian cancer, results are still preliminary but promising. Indocyanine green fluorescence imaging also is used for ureteral assessment, allowing intraoperative ureteral visualization, to reduce the risk of ureteral injury during gynecologic surgery.

CONCLUSIONS

For most gynecologic cancers, ICG fluorescence imaging is considered the tracer of choice for lymphatic mapping. The use of this new technology expands to a better ureteral assessment.

Role of carbon nanoparticle suspension in sentinel lymph node biopsy for early-stage cervical cancer: a prospective study

OBJECTIVE

To evaluate the clinical diagnostic validity of carbon nanoparticle suspension (CNS) in sentinel lymph node biopsy (SLNB) for assessing lymphatic spread of early-stage cervical cancer.

DESIGN

A prospective study.

SETTING AND POPULATION

356 cases.

METHODS

We enrolled 356 stage Ia2-IIa2 cervical cancer patients to undergo SLNB using CNS, followed by systematic pelvic lymphadenectomy. All lymph node specimens were assessed using conventional histopathologic ± pathologic ultrastaging analyses.

MAIN OUTCOME MEASURES

Sentinel lymph node detection rate (DR), clinical diagnostic validity and various related factors were analysed.

RESULTS

CNS identified 1456 SLNs in 325 patients. The overall SLN DR was 91.29%. A significantly higher DR was found for patients with tumours <20 mm (97.75% versus 71.91%; P < 0.001). Two patients had false-negative results. SLNB with CNS had sensitivity of 96.65%, false-negative rate (FNR) of 4.35% and negative predictive value (NPV) of 99.29%. Importantly, sensitivity (100%), NPV (100%) and FNR (0%) were improved when testing the subgroup of patients with tumours <20 mm (267 cases). There were no observed differences in DR based on pathological type or grade, stage, depth of stromal invasion, surgical approach, menopausal status or prior treatment with chemotherapy (P > 0.05).

CONCLUSIONS

Sentinel lymph node biopsy with CNS results in favourable DR, sensitivity and NPV for women with early-stage cervical cancer with small tumour sizes. SLNB with CNS is safe, feasible and relatively effective for guiding precise surgical treatment of early-stage cervical cancer.

TWEETABLE ABSTRACT

Sentinel lymph node biopsy with carbon nanoparticle suspension is safe and feasible for early-stage cervical cancer.

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.

Value of indocyanine green pelvic lymph node mapping in the surgical approach of cervical cancer

PURPOSE

Lymph node metastasis is a significant predictive factor for disease recurrence and survival in cervical cancer patients and relevant for therapeutic strategies. We evaluated the clinical value of indocyanine green (ICG) by measuring the sensitivity and negative predictive value of sentinel lymph node mapping compared with the gold standard of complete lymphadenectomy in detecting lymph node metastases for cervical cancer.

METHODS

We utilized the near-infrared imaging agent ICG to detect tumor-infested lymph nodes in the pelvis analogue to a classical sentinel lymph node procedure by analyzing data from 20 patients who had undergone surgery for cervical cancer at our institution. A laparoscopic lymph node mapping procedure by means of ICG, followed by a complete pelvic lymphadenectomy with or without paraaortic lymphadenectomy was done in all patients.

RESULTS

Histological examination identified seven patients with tumor-positive pelvic nodes, whereas mapping with ICG identified only five of these patients. Detection rate of positive nodes by ICG mapping and false negative rate was 71.4% and 28.6%, respectively; bilateral detection rate was 83.3%. One of the two false negative patients additionally suffered from deep infiltrating endometriosis.

CONCLUSIONS

Our results indicate that ICG can identify the relevant pelvic nodes independent of tumor size, provided bilateral detection is achieved and additional, related diseases are excluded.

TRIAL REGISTRATION

This trial is registered within the German Clinical Trial Register (DRKS-ID: DRKS00014692).

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.

Sentinel Lymph Nodes in Endometrial Cancer Update 2018

There are no established data about lymphadenectomy during treatment of endometrial cancers (ECs) and to what extent lymphadenectomy should be performed. In addition, retroperitoneal lymphadenectomy increases the intraoperative and postoperative complications. Sentinel lymph node (SLN) mapping has the lowest costs and highest quality-adjusted survival. SLN is the most cost-effective strategy in the management of low-risk ECs. Women staged with SLN mapping were more likely to receive adjuvant treatment compared with women staged with systemic lymphadenectomy. This review article designed to evaluate the diagnostic accuracy and the methods of SLN detection in ECs.

Clinical management of early-stage cervical cancer: The role of sentinel lymph node biopsy in tumors ≤2 cm

OBJECTIVE

To evaluate the experience with sentinel lymph node (SLN) biopsy in patients with early-stage cervical cancer at our hospital, and to analyze factors influencing the rate of false negatives.

STUDY DESIGN

This study was carried out at the Vall d'Hebron Hospital (Barcelona, Spain) between September 2000 and October 2016. All patients underwent SLN biopsy and systematic and bilateral pelvic lymphadenectomy, followed by radical hysterectomy. SLNs were analyzed by the pathologist by staining with hematoxylin-eosin and immunohistochemistry.

RESULTS

Patients (N = 128) had been diagnosed with early-stage cervical cancer (FIGO-2009 stages 1A2, IB1, and IIA1). The combined SLN detection rate (99-technecium and a blue dye) was 98.4%, bilateral in 76% of the patients. Positive SLNs were found in 19 patients (14.8%). Sensitivity of detection was 79.2% (CI95, 57.9-92.9), false negative rate 20.8% (CI95, 7.1-42.2), and negative predictive value 95.4% (CI95, 89.6-98.5). False negative cases were observed in 5 patients with tumors >2 cm and presenting lymphovascular space invasion. Micrometastases were detected during SLN ultrastaging in 3 patients (2.3%). The median follow-up was 8.24 years and the 5-year overall survival (OS) was 88.4% (CI95, 80.9-93.1).

CONCLUSION

SLN mapping and biopsy in early-stage cervical cancer is feasible and has high sensitivity to detect patients with initial metastases. The risk of false negatives could be lower in certain groups of patients, such as those with tumors ≤2 cm and no lymphovascular space invasion, but future studies will be required to test this hypothesis.

SLN mapping in early-stage cervical cancer as a minimal-invasive triaging tool for multimodal treatment

BACKGROUND

To evaluate sensitivity, false negative rate and negative predictive value of the combination of sentinel lymph node (SLN) mapping and frozen section (FS) in triaging cervical cancer patients to a definitive chemo-radiotherapy.

METHODS

A retrospective analysis of patients with histologically proven cervical cancer undergoing laparoscopic SLN mapping and frozen section of the SLNs followed by a completion radical hysterectomy, pelvic and/or paraarotic lymphadenectomy. Sensitivity, false negative rate and negative predictive value of the SLN mapping, of the frozen section and of the combination of the two in identifying micro- and macrometastases were calculated.

RESULTS

One-hundred and four patients with cervical cancer underwent surgery. Of these, 87 (83.7%) had bilateral detection rates at the SLN mapping and underwent FS evaluation and were selected for statistical analysis. Twenty-five patients had lymph nodal metastases at H&E staining. Of these, 24 displayed metastatic disease to the SLNs and one to a NSLN accounting for a FN rate of 4.0%. Metastases were identified in 21 patients at the FS analysis. Four patients had metastases in the SLNs that were missed at the FS analysis. The FN rate of the FS is 12.5% if we excluded isolated tumour cells in the analysis. The FN rate of the combined methodology (SLN mapping and FS of the SLN) is 16%. Twenty-one out of 25 patients (84.0%) could correctly be triaged to a definitive chemo-radiotherapy.

CONCLUSIONS

The combination of SLN mapping and FS of the SLNs is efficient in triaging patients to a definitive chemo-radiotherapy.