Sentinel lymph node mapping in endometrial cancer: comparison of fluorescence dye with traditional radiocolloid and blue

Different tracers for sentinel node detection in gynecologic oncology

PURPOSE OF REVIEW

In the past decade, sentinel lymph node (SLN) mapping has progressively substituted full lymphadenectomies in gynecologic oncology. In this article, we review the most relevant and the latest literature on this topic.

RECENT FINDINGS

In endometrial and cervical cancer, the current evidence further support the value of indocyanine green (ICG) as tracer of choice for SLN mapping. Experience in vulvar cancer is more limited, with ICG used together with technetium-99 m (Tc-99m) as a dual tracer but ICG, so far, has not been a game changer in this setting as it has been for cervical and endometrial cancer.

SUMMARY

For most gynecologic cancers, ICG fluorescence imaging is considered now a days the tracer of choice for lymphatic mapping. However, in early-stage vulvar cancer, SLN biopsy with radioactive tracer continues to be the standard-of-care in lymph node status assessment.

Validation of a semi-quantitative scoring system and workflow for analysis of fluorescence quantification in companion animals

Significance

Many commercially available near-infrared (NIR) fluorescence imaging systems lack algorithms for real-time quantifiable fluorescence data. Creation of a workflow for clinical assessment and post hoc analysis may provide clinical researchers with a method for intraoperative fluorescence quantification to improve objective outcome measures.

Aim

Scoring systems and verified image analysis are employed to determine the amount and intensity of fluorescence within surgical specimens both intra and postoperatively.

Approach

Lymph nodes from canine cancer patients were obtained during lymph node extirpation following peritumoral injection of indocyanine green (ICG). First, a semi-quantitative assessment of surface fluorescence was evaluated. Images obtained with a NIR exoscope were analysed to determine fluorescence thresholds and measure fluorescence amount and intensity.

Results

Post hoc fluorescence quantification (threshold of Hue = 165-180, Intensity = 30-255) displayed strong agreement with semi-quantitative scoring (k = 0.9734, p < 0.0001). Fluorescence intensity with either threshold of 35-255 or 45-255 were significant predictors of fluorescence and had high sensitivity and specificity (p < 0.05). Fluorescence intensity and quantification had a strong association (p < 0.001).

Conclusion

The validation of the semi-quantitative scoring system by image analysis provides a method for objective in situ observation of tissue fluorescence. The utilization of thresholding for ICG fluorescence intensity allows post hoc quantification of fluorescence when not built into the imaging system.

Research progress of indocyanine green fluorescence technology in gynecological applications

Indocyanine green is a near-infrared fluorescent dye which is widely used in various fields of surgery and gynecology. It is currently mainly used to detect various malignant tumors, sentinel lymph nodes, endometriosis lesions, ureter or intestinal occlusion, vaginal perfusion, uterine arterial blood perfusion, pelvic nerve, uterine niche, lymphatic edema, metastatic lesion shadow, and so on, providing new methods for decision-making during surgery. This article elaborates the application progress of indocyanine green fluorescence technology in gynecology.

The da Vinci robotic surgery system for the management of endometrial cancer: a single-center experience

The aim of this study was to report our single-center experience of the da Vinci robotic surgery system in the management of endometrial cancer (EC) patients during 2019-2023. We descriptively summarized the preoperative, intraoperative, and postoperative outcomes. Moreover, we conducted subgroup analyses based on obesity (BMI ≥ 30 kg/m2) and the intraoperative use of indocyanine green dye (ICG). Overall, 100 patients were analyzed. Eighty-five patients (85%) were obese. The mean operative time and estimated blood loss (EBL) were 240.84 ± 70.08 min (range: 110-720) and 104.2 ± 80.3 ml (range: 20-500), respectively. The mean number of retrieved pelvic LNs was 3.01 ± 3.06 (range: 0-15). The use of ICG was employed in 58 (58%). Only a single patient (1%) underwent conversion to laparotomy. Besides, only three (3%) patients experienced vaginal laceration intraoperatively, respectively. The mean hospital stay was 1.34 ± 0.69 days (range: 1-5). No patient experienced postoperative complications. Most tumors had endometrioid histology (82%), grade-1 tumor (49%), and stage-1A disease (67%). At 3-year follow-up, only two patients (2%) developed recurrence. Patients who received the ICG had significantly lower operative time (225.86 vs. 261.52 min, p = 0.011), estimated blood loss (90 vs. 123.81 ml, p = 0.037), and hospital stay (1.12 vs. 1.64 days, p < 0.001) compared with patients who did not receive it. However, there was no significant difference between both groups regarding the number of retrieved pelvic LNs. Obesity had no significant impact on the rates of intraoperative complications, postoperative complications, and 3-year recurrence incidence. In conclusion, robotic surgery was technically feasible and safe. The use of ICG was statistically linked to favorable outcomes, in terms of decreased operative time, EBL, and hospital stay. Obesity did not impact the perioperative surgical outcomes.

A hybrid radioactive and fluorescence approach is more than the sum of its parts; outcome of a phase II randomized sentinel node trial in prostate cancer patients

OBJECTIVE

To determine the diagnostic accuracy of the hybrid tracer indocyanine green (ICG)-Technetium-99 m(99mTc)-nanocolloid compared to sequential tracers of 99mTc-nanocolloid and free-ICG in detecting tumor-positive lymph nodes (LN) during primary surgery in prostate cancer (PCa) patients.

INTRODUCTION

Image-guided surgery strategies can help visualize individual lymphatic drainage patterns and sentinel lymph nodes (SLNs) in PCa patients. For lymphatic mapping radioactive, fluorescent and hybrid tracers are being clinically exploited. In this prospective randomized phase II trial, we made a head-to-head comparison between ICG-99mTc-nanocolloid (hybrid group) and 99mTc-nanocolloid and subsequent free-ICG injection (sequential group).

METHODS

PCa patients with a  >5% risk of lymphatic involvement according to the 2012 Briganti nomogram and planned for prostatectomy were included and randomized (1:1) between ultrasound-guided intraprostatic tracer administration of ICG-99mTc-nanocolloid (n = 69) or 99mTc-nanocolloid (n = 69) 5 h before surgery. Preoperative lymphoscintigraphy and SPECT/CT were performed to define the locations of the SLNs. Additionally, all participants in the sequential group received an injection of free-ICG at time of surgery. Subsequently, all (S)LNs were dissected using fluorescence guidance followed by an extended pelvic lymph node dissection (ePLND). The primary outcome was the total number of surgically removed (S)LNs and tumor-positive (S)LNs.

RESULTS

The total number of surgically removed (S)LN packages was 701 and 733 in the hybrid and sequential groups, respectively (p = 0.727). The total number of fluorescent LNs retrieved was 310 and 665 nodes in the hybrid and sequential groups, respectively (p < 0.001). However, no statistically significant difference was observed in the corresponding number of tumor-positive nodes among the groups (44 vs. 33; p = 0.470). Consequently, the rate of tumor-positive fluorescent LNs was higher in the hybrid group (7.4%) compared to the sequential group (2.6%; p = 0.002), indicating an enhanced positive predictive value for the hybrid approach. There was no difference in complications within 90 days after surgery (p = 0.78).

CONCLUSIONS

The hybrid tracer ICG-99mTc-nanocolloid improved the positive predictive value for tumor-bearing LNs while minimizing the number of fluorescent nodes compared to the sequential tracer approach. Consequently, the hybrid tracer ICG-99mTc-nanocolloid enables the most reliable and minimal invasive method for LN staging in PCa patients.

Non-invasive molecular imaging for precision diagnosis of metastatic lymph nodes: opportunities from preclinical to clinical applications

Lymph node metastasis is an indicator of the invasiveness and aggressiveness of cancer. It is a vital prognostic factor in clinical staging of the disease and therapeutic decision-making. Patients with positive metastatic lymph nodes are likely to develop recurrent disease, distant metastasis, and succumb to death in the coming few years. Lymph node dissection and histological analysis are needed to detect whether regional lymph nodes have been infiltrated by cancer cells and determine the likely outcome of treatment and the patient's chances of survival. However, these procedures are invasive, and tissue biopsies are prone to sampling error. In recent years, advanced molecular imaging with novel imaging probes has provided new technologies that are contributing to comprehensive management of cancer, including non-invasive investigation of lymphatic drainage from tumors, identifying metastatic lymph nodes, and guiding surgeons to operate efficiently in patients with complex lesions. In this review, first, we outline the current status of different molecular imaging modalities applied for lymph node metastasis management. Second, we summarize the multi-functional imaging probes applied with the different imaging modalities as well as applications of cancer lymph node metastasis from preclinical studies to clinical translations. Third, we describe the limitations that must be considered in the field of molecular imaging for improved detection of lymph node metastasis. Finally, we propose future directions for molecular imaging technology that will allow more personalized treatment plans for patients with lymph node metastasis.

Characteristics of systematic lymph node dissection and influencing factors of sentinel lymph node biopsy using carbon nanoparticles in endometrial carcinoma: a single-center study

BACKGROUND

Carbon nanoparticles (CNPs) are a new tracer for lymph node mapping, which can quickly reach and develop lymph nodes through a lymphatic network. This research investigated the characteristics of systematic lymph node dissection and sentinel lymph node biopsy mapped with CNPs in endometrial carcinoma.

METHODS

We first applied CNPs to systematic lymph node dissection in 18 endometrial carcinoma patients as the study group and another 18 endometrial carcinoma patients who were not injected with anything served as the control group. Then, we applied CNPs to sentinel lymph nodes biopsy in 54 endometrial carcinoma patients. All 54 patients received systematic lymph node dissection after sentinel lymph node biopsy. The detection rate, sensitivity, specificity, and accuracy of systematic lymph node dissection and sentinel lymph node biopsy by CNPs were respectively analyzed. A nomogram model for predicting the success of sentinel lymph node mapping was established.

RESULTS

The average number of lymph nodes removed in the CNP-labeled study group was higher than that in the control group (p<0.001). CNPs improved the number of lymph nodes with a diameter ≤ 0.5cm. The detection rate, sensitivity, specificity, and accuracy of sentinel lymph nodes biopsy by CNPs for endometrial carcinoma were 70.4%, 100%, 100%, and 100%, respectively. The nomogram model included factors of long menopause time, cervical cyst, and hard cervical texture, and the area of ROC curve was 0.816.

CONCLUSIONS

CNPs improve the detection rate of small lymph nodes. CNPs can trace sentinel lymph nodes in evaluating lymph node metastasis in endometrial carcinoma.

Tracers in Gastric Cancer Surgery

The treatment of gastric cancer mainly depends on radical gastrectomy. Determination of appropriate surgical margins and adequate lymph node (LN) resection are two major surgical steps that directly correlate with prognosis in gastric cancer. Due to the expanding use of minimally invasive procedures, it is no longer possible to locate tumors and LNs through touch. As an alternative, tracers have begun to enter the field due to their capacities for intraoperative visualization. Herein, we summarize the application of contemporary tracers in gastric cancer surgery, including isosulfan blue, methylene blue, patent blue, indocyanine green, carbon particles, and radioactive tracers. Their mechanisms, administration methods, detection efficiency, and challenges, as well as perspectives on them, are also outlined.

Applications and Safety of Sentinel Lymph Node Biopsy in Endometrial Cancer

Lymph node status is important in predicting the prognosis and guiding adjuvant treatment in endometrial cancer. However, previous studies showed that systematic lymphadenectomy conferred no therapeutic values in clinically early-stage endometrial cancer but might lead to substantial morbidity and impact on the quality of life of the patients. The sentinel lymph node is the first lymph node that tumor cells drain to, and sentinel lymph node biopsy has emerged as an acceptable alternative to full lymphadenectomy in both low-risk and high-risk endometrial cancer. Evidence has demonstrated a high detection rate, sensitivity and negative predictive value of sentinel lymph node biopsy. It can also reduce surgical morbidity and improve the detection of lymph node metastases compared with systematic lymphadenectomy. This review summarizes the current techniques of sentinel lymph node mapping, the applications and oncological outcomes of sentinel lymph node biopsy in low-risk and high-risk endometrial cancer, and the management of isolated tumor cells in sentinel lymph nodes. We also illustrate a revised sentinel lymph node biopsy algorithm and advocate to repeat the tracer injection and explore the presacral and paraaortic areas if sentinel lymph nodes are not found in the hemipelvis.

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.

The Role of Sentinel Lymph Node Mapping in High-grade Endometrial Cancer

OPINION STATEMENT

Total hysterectomy with lymph node assessment is the current standard-of-care for surgical staging in apparent early-stage endometrial cancer. Compared to the traditional complete pelvic lymphadenectomy with or without para-aortic lymphadenectomy, sentinel lymph node (SLN) mapping results in fewer surgical complications, decreased operative time, and lower rates of chronic lymphedema. The technique is endorsed by the National Comprehensive Cancer Network and the Society of Gynecologic Oncology guidelines, and over the past two decades the majority of gynecologic oncologists worldwide have adopted SLN mapping into their practice. However, as the results of the initial SLN studies were mostly based on low-grade tumors, adoption of the technique in high-grade tumors has been slower and more controversial. In this review, we discuss the most recent studies evaluating the SLN mapping in high-grade endometrial cancers. The results of these studies suggest that the SLN detection rate is acceptably high and the negative predictive value is sufficiently low to support the use of SLN mapping in high-grade endometrial tumors to replace complete lymphadenectomy. Validity of SLN mapping techniques does, however, require following a standard algorithm, and success depends also on surgeon expertise. Moreover, the impact of SLN mapping on overall survival in high-grade tumors requires future prospective randomized studies. Finally, a transition toward near-universal SLN mapping techniques for endometrial cancers could significantly impact on the adequacy of gynecologic oncology fellows' surgical training and competency in lymphadenectomy.

Comparison of Different Near-Infrared Technologies to Detect Sentinel Lymph Node in Uterine Cancer: A Prospective Comparative Cohort Study

OBJECTIVES

Sentinel lymph node biopsy is considered a crucial step in endometrial cancer staging. Cervical injection has become the most favored technique and indocyanine green has been demonstrated to be more accurate than other tracers. Different near-infrared camera systems are currently being used to detect indocyanine green in sentinel lymph nodes and have been compared in different patients. The present study aimed to determine the number and site of sentinel lymph nodes detected in the same patients with two different near-infrared technologies.

METHODS

This is a prospective, single-center, observational, non-sponsored study. Patients with presumed uterine-confined endometrial cancer were prospectively enrolled. After cervical injection, two different near-infrared cameras were used to detect sentinel lymph nodes at the same time: Olympus, Tokyo, Japan-considered the standard (SNIR); and Medtronic, Minneapolis, MN, USA with VISION SENSE^® which is a new laser near-infrared (LNIR) fluorescence laparoscope. The two cameras were alternatively switched on to detect sentinel lymph nodes in the same patients.

RESULTS

Seventy-four consecutive patients were included in the study. Most of the patients were diagnosed with endometrioid histology (62, 83.8%), FIGO stage IA (48, 64.9%), grade 2 (43, 58.1%), and underwent surgery with laparoscopic approach (70, 94.0%). The bilateral detection rate was 56/74 (75.7%) with SNIR and 63/74 (85.1%) with LNIR (p = 0.214). The total number of sentinel lymph nodes identified in the left hemipelvis was 65 and 70 with SNIR and LNIR, respectively; while in the right hemipelvis, there were 74 and 76, respectively. The median number of sentinel lymph nodes identified with SNIR and LNIR was 2 (range, 0-4) and 2 (range, 0-4), respectively (p = 0.370). No difference in site of sentinel lymph node detection was evident between the two technologies (p = 0.994). Twelve patients (16.2%) had sentinel lymph node metastasis: in all cases metastatic sentinel lymph nodes were detected both with Olympus and LNIR.

CONCLUSIONS

No difference in bilateral detection rate and number or site of sentinel lymph node detection was evident comparing two different technologies of near-infrared camera for ICG detection in endometrial cancer patients. No difference in sentinel lymph node metastases identification was detected between the two technologies.

Controversies in the Management of Early-stage Serous Endometrial Cancer

BACKGROUND/AIM

Early-stage uterine serous carcinoma (USC) has one of the highest recurrence rates and mortality among early-stage uterine epithelial cancers. Research into the clinical management of USC has begun to progress, guided by surgical and pathological advances. This article summarizes the available literature regarding diagnosis, management, and possible future uses of molecular analysis of women with early-stage USC.

MATERIALS AND METHODS

PubMed was searched for all pertinent English language research articles published from January 1, 2006 through March 1, 2020 which included a study population of women diagnosed with stage 1 USC. Due to the scarcity of prospective or large-scale data, studies were not limited by design or numbers of patients. Studies performed at earlier dates were incorporated to provide context.

RESULTS

A total of 86 studies were included in the review. Multiple well-designed studies have confirmed the safety of a minimally invasive surgical approach for surgical management of USC. The role of sentinel node biopsy has been validated with both prospective and retrospective multi-center data. Stage I USC is associated with a highly variable risk of recurrence, even following completion of adjuvant chemoradiation. This aggressive phenotype has been linked to high numbers of somatic copy number alterations, tumor protein 53, and phosphatidylinositol 3 kinase mutations, which have been shown to be predictive of prognosis.

CONCLUSION

Early-stage USC demonstrates a lack of predictable recurrence patterns, with reports noting distant recurrence in patients with disease confined to polyps. Unless no residual tumor is found on hysterectomy, chemotherapy and radiotherapy should be discussed and individualized by stage and treatment goals.

Comparison of SPECT-CT with intraoperative mapping in cervical and uterine malignancies

INTRODUCTION

The objective was to evaluate whether hybrid imaging combining single photon emission tomography with computed tomography (SPECT/CT) provides additional clinical value for dectection of sentinel lymph nodes (SLNs) compared with intraoperative combined mapping in uterine and cervical malignancies.

METHODS

This was a retrospective study of prospectively collected data from patients with stages IA-IB2 cervical cancer (International Federation of Gynecology and Obstetrics (FIGO) 2018) or stage I endometrial cancer, who underwent preoperative SPECT/CT for SLN detection. All included patients had dual injection of technetium-99m (^99mTc) with patent blue or indocyanine green.

RESULTS

A total of 171 patients were included with 468 SLNs detected during surgery: 146/171 patients (85.4%) had both radiotracer and blue injection whereas 25/171 patients (14.6%) had radiotracer and indocyanine green injected. The overall detection rate was 95.3%. The detection rate of SLN mapping was 74.9% for SPECT/CT, 90.6% for ^99mTc, 91.8% for blue dye, and 100% for indocyanine green. Bilateral drainage was found in 140 patients (81.9%), detected by ^99mTc in 105 patients (61.4%), by blue in 99 patients (67.3%), by indocyanine green in 23 patients (92%), and by SPECT/CT in 62 patients (36.4%). Atypical SLN locations were identified by SPECT/CT in 64 patients (37.4%), by 99mTc in 28 patients (16.4%), by blue in 17 patients (9.9%), and by indocyanine green in 8 patients (4.7%). Sensitivity and negative predictive value of SLN biopsy to detect lymph node metastasis using dual injection of different intraoperative combined techniques were 88.9% and 97.5%, respectively.

CONCLUSION

SPECT/CT enhanced topographic delineation of SLN and more accurately identified drainage to atypical locations. Fluorescent SLN mapping using indocyanine green offered the highest SLN detection rate. When indocyanine green was used, SPECT/CT did not increase SLN detection, and did not add further information to improve lymph node localization and removal.

Methylene Blue and Proflavine as Intraarterial Marker for Functional Perforazome-Comparative Study

Methylene blue (MB) is both a dye and a medicine known and used for a long time including as lymphatic tracer in melanoma and breast cancer for revealing sentinel lymph nodes. Proflavine (PRO) is an acriflavine dye, used as bacteriostatic disinfectant against many gram-positive bacteria that was also successfully applied to evaluate morphopathological changes in tissues. This study was performed on a group of twenty-eight Wistar rats and had as its main objective the in vivo evaluation of the use of MB and PRO as perforator tracers. The two dyes proved to be effective functional perforasome tracers with medium inflammatory infiltrate in the skin of the island perforator flap which heals perfectly at 14 days with complete absence of the inflammatory reaction. At the same injected amount, PRO seems to determine a greater inflammatory reaction compared with MB, but in smaller concentration, the inflammatory response is absent in the case of PRO. In conclusion, both substances tested within this in vivo study are good functional perforasome tracers, but PRO has the advantage of the absence of inflammatory reaction when using lower concentrations, while preserving unalerted its efficiency as tracer.

Lymphadenectomy in endometrial cancer - achieving more with less?

The lymph node status of patients with endometrial cancer is known to be a crucial determinant for the prognosis of the disease. It also provides the indication for further adjuvant treatment. The staging of endometrial cancer by surgery has been a controversial issue for more than 30 years. The significant complication rate after lymphadenectomy and the development of minimally invasive surgery have led to the use of sentinel lymph node (SLN) mapping. In the present review, we present the development of surgical staging procedures in patients with endometrial cancer and summarize the recently expanding body of published literature on the subject. SLN mapping is a safe and accurate technique, especially when indocyanine green is used as a tracer. SLN mapping appears to reduce complication rates as well as costs without affecting the oncologic outcome. Large prospective studies are needed to establish the effects of SLN mapping on the outcome of disease, especially in high-risk patients with endometrial cancer. Furthermore, the need for additional systematic lymphadenectomy prior to adjuvant radio-chemotherapy in patients diagnosed with isolated lymph node metastasis during SLN biopsy must be investigated further. This might pave the way for a new surgical approach in patients with endometrial cancer.

Complementary role of 18F-FDG PET/CT for sentinel lymph node algorithm in endometrial cancer with high-risk factors for lymphatic metastasis

OBJECTIVE

National Comprehensive Cancer Network (NCCN) sentinel lymph node (SLN) algorithm includes 'mandatory steps' for evaluating pelvic lymph nodes, but assessment of paraaortic area is left to surgeon's discretion. In this study, we aimed to investigate the complementary role of preoperative F-FDG PET/computed tomography (CT) scan in detecting pelvic and especially paraaortic lymphatic metastasis in endometrial cancer patients with high-risk factor(s) according to Mayo Clinic Criteria and underwent SLN algorithm.

METHODS

Patients who underwent preoperative F-FDG PET/CT scan, intraoperative SLN algorithm followed by systematic lymphadenectomy (LND) and had at least one high-risk criterion for lymphatic metastasis were included in this study. F-FDG PET/CT and SLN algorithm were compared with final histopathological results of systematic LND.

RESULTS

Thirty-eight patients were eligible for the study. Lymphatic metastasis was seen in 10 patients (26.3%). Four cases had paraaortic lymphatic metastases which were together with pelvic (n:2) or isolated (n:2) metastases. SLN algorithm was able to detect all pelvic lymph node metastases. However, isolated paraaortic metastases were diagnosed only by F-FDG PET/CT. In 76 hemipelvises, sensitivity and negative predictive value of SLN algorithm for diagnosis of pelvic nodal metastasis were 100%, while sensitivity, specificity, positive predictive value and negative predictive value of F-FDG PET/CT were 45.4, 95.3, 62.5 and 91.1%, respectively.

CONCLUSIONS

Although SLN algorithm has an excellent diagnostic value for pelvic nodal metastasis, paraaortic metastasis might be underdiagnosed. F-FDG PET/CT may be a feasible tool to exclude paraaortic lymphatic metastasis in high-risk patients for lymphatic metastasis who will undergo SLN algorithm.

Status of Sentinel Lymph Node Biopsy in Vulvar and Cervical Cancer

Assessment of lymphatic metastasis is an essential component of solid tumour staging. Sentinel lymph node (SLN) biopsy is a minimally invasive procedure that allows regional lymph node involvement by tumour to be estimated by selectively examining the sentinel lymph node while minimising the morbidity of systematic lymph node dissection. Within the group of genital cancers, the diagnostic value of SLN biopsy is rated differently. For selected patients with early-stage vulvar cancer (unifocal primary tumour < 4 cm, clinically negative inguinal lymph nodes) the SLN technique is already an established procedure in the guidelines of the German Society for Gynaecology and Obstetrics (DGGG)/German Cancer Society (DKG) and the recommendations of the European Society of Gynaecological Oncology (ESGO). For cervical cancer, SLN biopsy has not yet been sufficiently standardised but can be considered for patients without risk factors with a primary tumour size < 2 cm. The SLN is identified by combined use of radioactive ^99m technetium nanocolloid and patent blue. The use of indocyanine green offers an alternative for SLN identification with few side effects. Recent studies aim to increase the diagnostic reliability of intraoperative frozen section analysis as this continues to show limited sensitivity in both vulvar and cervical cancer. The rate of detection of micrometastases can be increased by additional ultrastaging, the prognostic significance of which for both diseases is still unclear. The prognostic value of SLN biopsy compared with systematic lymph node dissection is being investigated in current studies (GROINSS-V-II for vulvar cancer and SENTIX-, SENTICOL-3 for cervical cancer). For this review article, a guideline-based literature search was performed in the National Library of Medicine (PubMed/MEDLINE) database with a particular focus on recent cohort studies and conference contributions.

Identification and preservation of stained non-sentinel lymph nodes in breast cancer

Sentinel lymph nodes (SLNs) are the first lymph nodes that receive lymphatic drainage from the breast. However, all stained lymph nodes are dissected as SLNs during surgery. The present study aimed to identify and preserve the stained non-SLNs and evaluate the safety during sentinel lymph node biopsy (SLNB) in breast cancer. SLNB was performed with a methylene blue and indocyanine green double-tracer technique. The first lymph node, which was connected with lymphatic vessels from the breast, was designated as the true SLN. The lymph node that was directly connected with the output lymphatic duct of the SLN was defined as post-SLN (poSLN), whereas the stained poSLN was designated as non-SLN. Both the stained SLN and non-SLN were sent to the pathological department for definitive diagnosis. The present study demonstrated that intraoperative dissection of the lymphatic network could distinguish true SLNs and stained non-SLNs. The number of stained lymph nodes was time-dependent. Not all stained lymph nodes were real SLNs, whereas the poSLNs would be stained if the staining time interval was inappropriate. The data indicated that the poSLNs were negative for metastasis when the SLNs were negative for metastasis. Stained lymph nodes may contain non-SLNs in addition to SLNs. Resection of all stained lymph nodes is not recommended. To reduce the morbidity due to SLNB complications, the identification and preservation of stained non-SLNs during SLNB is feasible and warrants further study in the era of precision medicine.

Sentinel lymph node biopsy in endometrial cancer: state of the art

Endometrial cancer (EC) is the most common gynecological neoplasm in developed countries. In literature, there are discordant data regarding the therapeutic value of systematic lymphadenectomy whereas the importance of lymph node status for determining prognosis and the need for adjuvant treatment is undoubted. Given the low risk of lymph-node metastases in the apparent early-stage disease and the significant surgical and postoperative risks when performing a complete pelvic lymphadenectomy, the surgical approach in these patients is controversial, ranging from no nodal evaluation to comprehensive pelvic and aortic lymphadenectomy. The recent introduction of sentinel node mapping represents the mid-way between the execution and omission of node dissection in EC patients. Indeed, the sentinel node mapping has rapidly emerged as an alternative to complete lymphadenectomy to reduce morbidity. In the present review, we discuss the role of sentinel node mapping in the surgical management of EC evaluating all aspects of this procedure.

Sentinel lymph node detection by means of indocyanine green using the Karl Storz VITOM® fluorescence camera: a comparison between primary sentinel lymph node biopsy versus sentinel lymph node biopsy after neoadjuvant chemotherapy

PURPOSE

The usage of radioactive Technetium^99m (Tc^99m) colloid for the purpose of sentinel lymph node biopsy (SLNB) in early breast cancer is considered the gold standard in Germany. However, new tracers, such as near-infrared (NIR) imaging agents like indocyanine green (ICG) could offer an alternative in future, as they overcome drawbacks associated with radioactive Technetium^99m (Tc^99m) like limited availability, high costs and radioactivity exposure for both patients and surgeons.

METHODS

In this double-arm retrospective study, we sought to establish the usefulness of indocyanine green as an alternative or an addition to the conventional Technetium^99m (Tc^99m) in the identification of the SLN in early breast cancer.

RESULTS

Among the 161 patients who underwent primary SLNB, 34 patients had at least 1 SLN with metastasis. Among these patients with SLN metastasis, 33 had the SLN detected by ICG; while 31 had the SLN detected by Tc^99m. The conventional Technetium^99m radiotracer failed to detect 2 patients with metastasis in this Arm of the study. Among the 87 patients who underwent SLNB after NACT, 13 patients had at least 1 SLN with metastasis. Among these 13 patients with SLN metastasis, ICG and Tc^99m had detected the SLN among 12 patients, while 1 patient had been detected by ICG alone.

CONCLUSIONS

Our results show that ICG is as effective as the radioisotope for SLNB even among patients who have undergone NACT. This trial is registered with the German Clinical Trial Register, ID: DRKS00013606.

The role of sentinel lymph node mapping in endometrial carcinoma

Endometrial cancer is the most commonly diagnosed gynecological malignancy in developing countries, and the second malignancy after cervical cancer in developing countries. The primary treatment is based on surgical and pathologic staging including extrafascial type A radical hysterectomy bilateral salpingo-oophorectomy and pelvic and latero-aortic lymphadenectomy. Minimally invasive surgery is the most widely used technique. Sentinel node biopsy is part of this concept and has reached the management of endometrial cancer. The aim of this review was to describe the history, the different injection techniques and results of sentinel node biopsy, and analyze the future role of this technique in endometrial carcinoma.

Systematic review and meta-analysis concerning near-infrared imaging with fluorescent agents to identify the sentinel lymph node in oncology patients

Sentinel node procedures (SNP) are performed with the use of tracer-agents, mainly radio-colloid and/or blue dye. Fluorescent agents have emerged as a new tracer-agent to identify the SLN intra-operatively with near-infrared imaging. Our aim is to compare the detection rate of fluorescent agents to current "golden standards" (blue dye and/or radio-colloid) for the SNP by means of a systematic review and meta-analysis without any restrictions based on tumor type. A systematic search in PubMed, Embase and The Cochrane Library was performed. Articles that compared the detection rates of fluorescent agents with radio-colloid and/or blue dye were included. Meta-analyses were performed for breast, gynecological and dermatological cancer using a random effects model. In total 6195 articles were screened which resulted in a final inclusion of 55 articles. All studies used indocyanine green (ICG) as fluorescent agent. Meta-analyses comparing ICG with blue dye showed a significant and clinically relevant difference in detection rate in favor of ICG, for both breast, dermatological and gynecological cancer. Meta-analyses comparing ICG with radio-colloid did not show any significant differences, with the exception of ICG versus radio-colloid + blue dye for the bilateral SLN detection in gynecological cancer. Near-infrared fluorescence imaging using ICG provides a higher detection rate compared to blue dye for the SNP in a range of different tumor types. SLN detection rates of ICG are comparable to radio-colloid. Due to their complementary characteristics in terms of spatial resolution and transdermal sensitivity, we suggest to use a combination of both ICG and a radio-colloid.

Evaluation of quality of life, body image and surgical outcomes of robotic total laparoscopic hysterectomy and sentinel lymph node mapping in low-risk endometrial cancer patients - A Robotic Gyne Club study

INTRODUCTION

The aims of the study were to evaluate quality of life, cosmetic results and surgical outcomes of robotic single-site and robotic multiport total laparoscopic hysterectomy with sentinel lymph node mapping in women treated for low-risk endometrial cancer.

MATERIAL AND METHODS

The study is a prospective, multicenter, case-control study conducted at Ospedale Santa Chiara in Trento and Novara and Pavia University Hospitals. Seventy-six consecutive patients with a biopsy-confirmed diagnosis of low-risk endometrial cancer or atypical endometrial hyperplasia who between January 2017 and January 2019 had undergone robotic total laparoscopic hysterectomy and sentinel lymph node mapping were included. Data on surgical outcomes, quality of life and cosmetic results were prospectively collected and analyzed based on the surgical approach with robotic single-site vs robotic multiport assistance. Patients' clinical characteristics, intra-operative parameters, sentinel lymph node mapping results and postoperative findings were prospectively recorded. Clinical follow up was performed 4 weeks and 6 and 12 months after surgery. Fifty-one patients underwent a robotic multiport procedure and 25 patients a robotic single-site surgery.

RESULTS

There was one significant difference between the two groups in terms of patient characteristics: mean body mass index (BMI) in the multiport group was 29 kg/m² vs 24.8 kg/m² in the single-site group (P value <.001). After univariate and multivariate analysis on intraoperative and postoperative findings, a shorter surgical time was observed in the single-site cohort than in the multiport group (148.7 vs 158.2 minutes, P value .0182). BMI also had a significant effect on surgical time (P = .022). No differences were seen in terms of sentinel lymph node detection: the bilateral detection rate was 96.1% for multiport (66.7% bilateral, 29.4% monolateral) and 96% for single-site (76% bilateral, 20% monolateral) procedures. No differences between the two approaches were identified with regard to postoperative complications, pain, cosmetic results or quality of life comparisons.

CONCLUSIONS

For the treatment of low-risk endometrial cancer and atypical endometrial hyperplasia with total hysterectomy and sentinel lymph node mapping, the robotic single-port approach is comparable to the multiport procedure in terms of intraoperative and postoperative findings, and has an advantage in terms of shorter surgical times. Further studies are required to identify possible differences in quality of life and cosmetic results.

Technetium-99m-indocyanine green versus technetium-99m-methylene blue for sentinel lymph node biopsy in early-stage endometrial cancer

INTRODUCTION

The low accuracy of pre-operative imaging techniques for prediction of nodal status strengthens the relevance of sentinel lymph node (SLN) biopsy in endometrial cancer, although the optimal method for its detection is still under investigation. The increasing use of indocyanine green (ICG) has aroused concern about its enhanced visualization of lymphatic channels, which could lead to a specimen that is thought to be nodal tissue not subsequently yielding a lymph node on pathologic analysis ('empty node packet'). Our main objective was to compare the overall and bilateral detection rates for SLN biopsy using two combined techniques: technetium-99m-ICG (Tc-99m-ICG) versus technetium-99m-methylene blue (Tc-99m-MB). Our secondary aim was to compare the 'empty node packet' rates between the two cohorts.

METHODS

A prospective, non-randomized, single-center trial including patients diagnosed with endometrial cancer (any grade or histology) in pre-operative early stage, and operated on between February 2017 and July 2019. All tracers were injected intracervically. Pelvic and aortic lymphadenectomy were performed on patients at intermediate or high risk of recurrence pre-operatively. All SLNs were sent for intra-operative frozen section and afterwards processed following an ultrastaging protocol.

RESULTS

Eighty-four patients were included, 58% (n=49) in the Tc-99m-MB group and 42% (n=35) in the Tc-99m-ICG group. Overall detection rate was 93% and was not statistically different between the two groups. A better bilateral detection rate was observed among Tc-99m-ICG patients (69% vs 41%, p=0.012). The 'empty node packet' rate was 4% in the Tc-99m-ICG cohort and 0% in the Tc-99m-MB cohort (p=0.032).

DISCUSSION

Tc-99m-ICG is a feasible, safe technique for SLN biopsy in early-stage endometrial cancer, and appears to be superior in terms of bilateral detection to Tc-99m-MB. The addition of Tc-99m to ICG could decrease the rate of 'empty node packets' and better define the anatomic location of SLNs in patients with endometrial cancer.

Sentinel lymph node biopsy in early stage endometrial cancer: a Turkish gynecologic oncology group study (TRSGO-SLN-001)

OBJECTIVE

The aim of this multicenter study was to evaluate the feasibility of sentinel lymph node (SLN) mapping in clinically uterine confined endometrial cancer.

METHODS

Patients who underwent primary surgery for endometrial cancer with an SLN algorithm were reviewed. Indocyanine green or blue dye was used as a tracer. SLNs and/or suspicious lymph nodes were resected. Side specific lymphadenectomy was performed when mapping was unsuccessful. SLNs were ultrastaged on final pathology.

RESULTS

357 eligible patients were analyzed. Median age was 59 years. Median number of resected SLNs was 2 (range 1-12) per patient. Minimal invasive and open surgeries were performed in 264 (73.9%) and 93 (26.1%) patients, respectively. Indocyanine green was used in 231 (64.7%) and blue dye in 126 (35.3%) patients. The dyes were injected into the cervix in 355 (99.4%) patients. The overall and bilateral SLN detection rates were 91.9% and 71.4%, respectively. The mapping rates using indocyanine green or blue dye were comparable (P=0.526). There were 43 (12%) patients with lymphatic metastasis. The SLN algorithm was not able to detect 3 of 43 patients who had isolated paraaortic metastasis. After SLN biopsy, complete pelvic lymphadenectomy was performed in 286 (80.1%) patients. Sensitivity and negative predictive value were both 100% for the detection of pelvic lymph node metastases. In addition, 117 (32.8%) patients underwent completion paraaortic lymphadenectomy after SLN biopsy. In these patients, sensitivity for detecting metastases to pelvic and/or paraaortic lymph nodes was 90.3% with a negative predictive value of 96.6%. The risk of non-SLN involvement in patients with macrometastatic SLNs, micrometastatic SLNs, and isolated tumor cells in SLNs were 61.2%, 14.3% and 0%, respectively.

CONCLUSIONS

SLN biopsy had good accuracy in detecting lymphatic metastasis. However, one-third of cases with metastatic SLNs also had non-SLN involvement and this risk increased to two-thirds of cases with macrometastatic SLNs. The effect of leaving these nodes in situ on survival should be evaluated in further studies.

Peritoneal contamination with ICG-stained cervical secretion as surrogate for potential cervical cancer tumor cell dissemination: A proof-of-principle study for laparoscopic hysterectomy

INTRODUCTION

Intracorporal colpotomy during radical hysterectomy for cervical cancer is discussed to be a risk factor for peritoneal dissemination of tumor cells. It might lead to increased recurrence rates after laparoscopic radical hysterectomy compared with abdominal hysterectomy, as shown by the recent LACC study. Data on the frequency or mechanisms of peritoneal contamination are missing. We aimed to analyze peritoneal contamination of cervical secretion during intracorporal colpotomy with a novel indocyaningreen (ICG)-based technique.

MATERIAL AND METHODS

In this prospective proof-of-principle study, patients undergoing routine laparoscopic or robot-assisted hysterectomy were selected. ICG was specifically applied to the cervical surface and routine surgery was performed. During colpotomy, pictures under white and fluorescence light were taken to evaluate frequency of contamination.

RESULTS

By using cervically applied ICG we were able to visualize directly peritoneal contamination with cervical secretion during intracorporal colpotomy. We detected peritoneal contamination in 9/12 (75%) patients undergoing routine laparoscopic hysterectomy. Contamination of laparoscopic instruments occurred in 60% of the patients. When contamination occurred, it was routinely detectable during all steps of colpotomy. There were no adverse effects during surgery.

CONCLUSIONS

Peritoneal contamination with cervical secretion frequently occurs during intracorporal colpotomy. This novel technique represents a promising tool for feasible and direct visualization of peritoneal contamination during colpotomy. The technique may be easily implemented in further studies on laparoscopic and abdominal hysterectomy and serve as a quality assessment tool for surgeons and surgical techniques.

Triple tracer (blue dye, indocyanine green, and Tc99) compared to double tracer (indocyanine green and Tc99) for sentinel lymph node detection in endometrial cancer: a prospective study with random assignment

OBJECTIVE

Sentinel lymph node (SLN) mapping is increasingly being used in the treatment of apparent early-stage endometrial cancer. The aim of this study was to evaluate whether three tracers (blue dye, indocyanine green (ICG), and technetium-99 (Tc99)) performed better than two (ICG and Tc99).

STUDY DESIGN

Prospective study of all consecutive patients (n=163) diagnosed with clinical early-stage endometrial cancer from 2015 to 2017. All patients were randomly assigned to receive a mixture of ICG and Tc99 with or without blue dye. Subgroup analysis for detection rates was performed for each group (double versus triple tracer).

RESULTS

One hundred and fifty-seven patients met the inclusion criteria. Eighty patients received ICG and Tc99 with unilateral and bilateral SLN detection rates of 97.5% and 81.3%, respectively. Seventy-seven patients received all three tracers with unilateral and bilateral detection rates of 93.5% and 80.5%, respectively. Only one patient in the triple tracer group was detected by blue dye alone. No significant differences were noticed in unilateral or bilateral detection rates between the two groups, nor in the detection of lymph node metastasis.

CONCLUSION

The addition of blue dye to ICG and Tc99 did not demonstrate any improvement in SLN detection.

Current landscape and future perspective of sentinel node mapping in endometrial cancer

Endometrial cancer (EC) represents the most common gynecological neoplasm in developed countries. Surgery is the mainstay of treatment for EC. Although EC is characterized by a high prevalence several features regarding its management are still unclear. In particular the execution of lymphadenectomy is controversial. The recent introduction of sentinel node mapping represents the mid-way between the execution and omission of node dissection in EC patients. In the present review we discuss the emerging role of sentinel node mapping in EC. In addition, we discussed how type of tracers utilized and site of injection impacted on sentinel node detection rates. Future perspective regarding EC management are also discussed.

The role of sentinel node in early ovarian cancer: a systematic review

INTRODUCTION

Early ovarian cancer (EOC) is defined as ovarian cancer macroscopically limited to the ovaries at the time of initial diagnosis. Approximately only 25% of patients with ovarian cancer are affected by EOC. This condition requires complete surgical staging, including systematic lymphadenectomy up to the level of the renal vessels, with the consequent risk of complications and morbidity. With the aim to reduce the procedure-related morbidity, sentinel lymph node mapping (SLNm) has been introduced as an experimental procedure in EOC staging. The aim of the present study is to systematically review the available series on this interesting issue.

EVIDENCE ACQUISITION

Studies were identified by searching electronic databases. The search was systematically applied to PubMed, ClinicalTrials.gov, Scopus and Web of Science looking for records describing the use of sentinel lymph node technique in EOC from January 1st, 1989 to January 1st, 2019. A total of 10 studies were identified for inclusion. Of the 121 patients involved in these studies, only 43 had a histologically-confirmed diagnosis of EOC and were included in the present analysis.

EVIDENCE SYNTHESIS

SLN (paraaortic and/or pelvic) overall detection rate (DR) was of 97.6%. The overall sensitivity (SS) and negative predictive value (NPV) of the included cases were 66.7% and 96.6%, respectively. We calculated also NPV, SS and DR based on the anatomical lymph node district, with a value of 100% both in the lumbo-aortic and in the pelvic district and a DR of 83.3% and 43% respectively.

CONCLUSIONS

This review shows that evidence on SLNm in EOC is still scant. Based on the limited data available, SLNm may provide potentially useful information on nodal status in patients affected by this disease.

Evaluation of Patent Blue as the Vital Dye in an Animal Model of Descemet Membrane Endothelial Keratoplasty

PURPOSE

To evaluate the safety and feasibility of patent blue (PB) as the vital dye in Descemet membrane endothelial keratoplasty (DMEK).

METHODS

Bovine corneal endothelial cells were incubated with different concentrations (0.02%-2.5%) of PB. The cell viability, which was assessed by Cell Counting Kit-8 assay, was compared with that of untreated control and 0.06% to 0.4% trypan blue. The dyes were also used for graft preparation and implantation in the porcine eye model to evaluate stain quality, dye retention, and the feasibility of using PB in DMEK surgery.

RESULTS

No obvious increase in cytotoxicity was detected for 0.06% to 0.4% trypan blue and PB at concentrations up to 1.0%, but the cell viability after incubating with 1.5% to 2.5% PB was significantly reduced. PB at 0.5% to 1.0% generated good staining quality that can be used to facilitate graft implantation. Although the staining quality of 0.5% to 1.0% PB faded to an intermediate level after a 30-minute wash in phosphate-buffered saline, dye retention persisted for up to 24 hours.

CONCLUSIONS

PB at 0.5% to 1.0% is biocompatible and can stain the graft sufficiently, making it an alternative for DMEK surgery.

Surgical staging in endometrial cancer

In several malignancies, it has been demonstrated that the lymph nodal status is the most important pathologic factor affecting prognosis and giving the indication to further adjuvant treatment. The surgical assessment of the lymph nodal status in endometrial cancer is debated since 30 years. Recently, the sentinel lymph node mapping is rapidly gaining clinical acceptance in endometrial cancer. The adoption of Indocyanine Green as a safe and user friendly tracer for sentinel lymph node mapping increased the speed to which this procedure is getting applied in clinical practice. As a consequence of this rapid growth, several fundamental questions have been raised and are still debatable. In this manuscript, we discuss the importance of a known pathological lymph nodal status, the technique of the sentinel lymph node mapping with the reported false negative rates and detection rates according to the different tracers adopted, and the clinical scenarios in which a sentinel lymph node mapping could be employed.

Comparison Study of Laparoscopic Sentinel Lymph Node Mapping in Endometrial Carcinoma Using Carbon Nanoparticles and Lymphatic Pathway Verification

STUDY OBJECTIVE

To evaluate the detection rate and accuracy of sentinel lymph node (SLN) mapping using cervical and fundal injections of carbon nanoparticles (CNPs) in laparoscopic surgery of endometrioid endometrial cancer (EC) and to identify uterine lymphatic drainage pathways validated by mapping.

DESIGN

A prospective consecutive study (Canadian Task Force classification II-2).

SETTING

An academic research center.

PATIENTS

Consecutive patients with a pathologic diagnosis of early-stage EC scheduled for primary laparoscopic-assisted staging surgery (laparoscopic hysterectomy, bilateral salpingo-oophorectomy, or comprehensive lymphadenectomy).

INTERVENTIONS

Enrolled patients underwent laparoscopic SLN mapping with a 50-mg CNP tracer injection. Fifty patients received fundal subserosal injections at 4 sites (the fundal group), whereas 65 patients received cervical submucosal injections at 2 sites (the cervical group). After SLN mapping, all patients underwent laparoscopic staging surgery.

MEASUREMENTS AND MAIN RESULTS

No allergic reactions to CNPs were observed in either group. The overall SLN detection rates were 100% and 92% in the cervical and fundal groups, and the bilateral SLN detection rates were 97% and 68% (p < .001), respectively. A total of 12 metastatic SLNs were accurately detected in 5 patients. The sensitivity of metastatic lymph node detection was 100% in the cervical group, which is higher than that in the fundal group (80%). The false-negative rates were 0% and 20%, respectively, in the cervical and fundal groups. Furthermore, we verified 3 uterine lymphatic pathways using the 2 injection methods. The upper paracervical pathway was the most common drainage pathway in both groups (91.4% in the cervical group vs 80.24% in the fundal group), whereas the infundibulopelvic pathway was observed only in the fundal group (15.11%).

CONCLUSION

SLN mapping by CNPs in laparoscopic surgery for EC is a safe and effective alternative, with a higher detection rate and better accuracy with cervical injections than fundal injections. The upper paracervical pathway was the most common lymphatic pathway, whereas the infundibulopelvic pathway was only displayed in fundal injections.

Sentinel node biopsy for treatment of endometrial cancer: current perspectives

The risk of lymph nodal metastases in endometrial cancer varies greatly according to the characteristics of the primary tumor. Surgical staging with a systematic lymphadenectomy in endometrial cancer is debated since three decades. On one hand, it provides important pathological information on the spread of the tumor allowing for an appropriate decision making on adjuvant treatment but on the other side it is characterized by a non-negligible short and long-term morbidity. In the past decade, various efforts have been made in the attempt to apply the concept of the sentinel lymph node mapping in endometrial cancer. The sentinel lymph node mapping has the potential to provide the necessary pathological lymph nodal information at a reasonable cost in terms of morbidity. In this review, the most relevant aspects of the sentinel lymph node mapping in endometrial cancer are summarized. Furthermore, the performance in terms of false negative rates and detection rates, the clinical value of the pathological ultrastaging, its clinical applicability in different scenarios including patients preoperatively considered to be at low or at high risk are discussed. Oncological outcome of the patients who have been submitted to a sentinel lymph node mapping as compared to a full lymhadenectomy are presented as well as technical aspects to improve the performance of the surgical technique.

Near-infrared fluorescence for detection of sentinel lymph nodes in women with cervical and uterine cancers (FILM): a randomised, phase 3, multicentre, non-inferiority trial

BACKGROUND

Accurate identification of sentinel lymph nodes in patients with cancer improves detection of metastatic disease and decreases surgical morbidity. We sought to establish whether indocyanine green fluorescent dye is non-inferior to isosulfan blue dye in detecting sentinel lymph nodes in women with cervical and uterine cancers.

METHODS

In this non-inferiority, within-patient comparison study, patients aged 18 years or older with clinical stage I endometrial or cervical cancer undergoing curative surgery were randomly assigned 1:1 to lymphatic mapping with isosulfan blue dye (visualised by white light) followed by indocyanine green (visualised by near-infrared imaging), or indocyanine green followed by isosulfan blue dye. Permuted block randomisation with stratification by study site was done with a computerised random number generator. All participants were masked to their randomisation assignment until after the procedure; however, investigators were not masked to the procedure used. Laparoscopic surgery with the PINPOINT near-infrared fluorescence imaging system (Stryker, Kalamazoo, MI, USA) was used in all cases. The primary outcome was efficacy of intraoperative indocyanine green with near-infrared fluorescence imaging versus that of isosulfan blue dye in the identification of lymph nodes, defined as the number of lymph nodes identified by indocyanine green and isosulfan blue dye, respectively (and confirmed as lymphoid tissue by histology), divided by the number of lymph nodes identified intraoperatively and excised. The study had a 5% non-inferiority margin needed to show non-inferiority of the frequency of lymph node detection with indocyanine green to that with isosulfan blue dye with 80% power at a 5% two-sided significance level. Analyses were done in both per-protocol and modified intention-to-treat populations. The trial was registered with ClinicalTrials.gov, number NCT02209532, and is completed and closed.

FINDINGS

Between Dec 21, 2015, and June 19, 2017, 180 patients were enrolled and randomly assigned to the two groups (90 to each group); 176 patients received the intervention and were evaluable (modified intention-to-treat population). 13 patients with major protocol violations were subsequently excluded from the per-protocol population. 517 sentinel nodes were identified in the per-protocol population (n=163), of which 478 (92%) were confirmed to be lymph nodes on pathological processing: 219 (92%) of 238 nodes that were both blue and green, all seven nodes that were blue only, and 252 (95%) of 265 nodes that were green only (p=0·33). Seven sentinel lymph nodes were neither blue nor green but were removed for appearing suspicious or enlarged on visual examination. In total, 471 (97%) of 485 lymph nodes were identified with the green dye and 226 (47%) with the blue dye (difference 50%, 95% CI 39-62; p<0·0001). In the modified intention-to-treat population (n=176), 545 nodes were identified, of which 513 (94%) were confirmed to be lymph nodes on pathological processing: 229 (92%) of 248 nodes that were both blue and green, all nine nodes that were blue only, and 266 (95%) of 279 nodes that were green only (p=0·30). Nine sentinal lymph nodes were neither blue nor green but were removed for appearing suspicious or enlarged on visual examination. 495 (96%) of 513 nodes were identified with the green dye and 238 (46%) with the blue dye (50%, 39-61; p<0·0001).

INTERPRETATION

Indocyanine green dye with near-infrared fluorescence imaging identified more sentinel nodes than isosulfan blue dye in women with cervical and uterine cancers, with no difference in the pathological confirmation of nodal tissue between the two mapping substances.

FUNDING

Novadaq.

Molecular Imaging of endometrial sentinel lymph nodes utilizing fluorescent-labeled Tilmanocept during robotic-assisted surgery in a porcine model

Molecular imaging with a fluorescent version of Tilmanocept may permit an accurate and facile detection of sentinel nodes of endometrial cancer. Tilmanocept accumulates in sentinel lymph nodes (SLN) by binding to a cell surface receptor unique to macrophages and dendritic cells. Four female Yorkshire pigs underwent cervical stromal injection of IRDye800-Tilmanocept, a molecular imaging agent tagged with near-infrared fluorescent dye and radiolabeled with gallium-68 and technetium-99m. PET/CT scans 1.5 hours post-injection provided pre-operative SLN mapping. Robotic-assisted lymphadenectomy was performed two days after injection, using the FireFly imaging system to identify nodes demonstrating fluorescent signal. After removal of fluorescent nodes, pelvic and periaortic node dissections were performed. Nodes were assayed for technetium-99m activity, and SLNs were established using the “10%-rule”, requiring that the radioactivity of additional SLNs be greater than 10% of the “hottest” SLN. Thirty-four nodal samples were assayed ex vivo for radioactivity. All the SLNs satisfying the “10%-rule” were detected using the FireFly system. Five fluorescent nodes were detected, corresponding with preoperative PET/CT scan. Three pigs had one SLN and one pig had two SLNs, with 100% concordance between fluorescence and radioactivity. Fluorescent-labeled Tilmanocept permits real-time intraoperative detection of SLNs during robotic-assisted lymphadenectomy for endometrial cancer in a porcine model. When radiolabeled with gallium-68, Tilmanocept allows for preoperative localization of SLNs using PET/CT, and shows specificity to SLNs with persistent fluorescent signal, detectable using the FireFly system, for two days post-injection. In conclusion, these findings suggest that a phase I trial in human subjects is warranted, and that a long-term goal of an intra-operative administration of non-radioactive fluorescent-labeled Tilmanocept is possible.

Retrospective validation of the laparoscopic ICG SLN mapping in patients with grade 3 endometrial cancer

PURPOSE

To evaluate the sensitivity, negative predictive value (NPV) and false-negative (FN) rate of the near infrared (NIR) indocyanine green (ICG) sentinel lymph node (SLN) mapping in patients with poorly differentiated endometrial cancer who have undergone a full pelvic and para-aortic lymphadenectomy after SLN mapping.

METHODS

We performed a retrospective analysis of patients with endometrial cancer undergoing a laparoscopic NIR-ICG SLN mapping followed by a systematic pelvic and para-aortic lymphadenectomy. Inclusion criteria were a grade 3 endometrial cancer or a high-risk histology (papillary serous, clear cell carcinoma, carcinosarcoma, and neuroendocrine carcinoma) and a completion pelvic and para-aortic lymphadenectomy to the renal vessels after SLN mapping. Overall and bilateral detection rates, sensitivity, NPV, and FN rates were calculated.

RESULTS

From December 2012 until January 2017, 42 patients fulfilled inclusion criteria. Overall and bilateral detection rates were 100 and 90.5%, respectively. Overall, 23.8% of the patients had lymph node metastases. In one patient, despite negative bilateral pelvic SLNs, a metastatic non-SLN-isolated para-aortic metastasis was detected. This NSLN was clinically suspicious and sent to frozen section analysis during the surgery. FN rate, sensitivity, and NPV were 10, 90, and 97.1%, respectively. For the SLN mapping algorithm, FN rate, sensitivity, and NPV were 0, 100, and 100%, respectively.

CONCLUSIONS

Laparoscopic NIR-ICG SLN mapping in high-risk endometrial cancer patients has acceptable sensitivity, FN rate, and NPV.