Laparoscopic sentinel node procedure using a combination of patent blue and radiocolloid in women with endometrial cancer

Risk factors associated with false negative rate of sentinel lymph node biopsy in endometrial cancer: a systematic review and meta-analysis

Objective

Currently, sentinel lymph node biopsy (SLNB) is increasingly used in endometrial cancer, but the rate of missed metastatic lymph nodes compared to systemic lymph node dissection has been a concern. We conducted a systematic review and meta-analysis to evaluate the false negative rate (FNR) of SLNB in patients with endometrial cancer and to explore the risk factors associated with this FNR.

Data sources

Three databases (PubMed, Embase, Web of Science) were searched from initial database build to January 2023 by two independent reviewers.

Research eligibility criteria

Studies were included if they included 10 or more women diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I or higher endometrial cancer, the study technique used sentinel lymph node localization biopsy, and the reported outcome metrics included false negative and/or FNR.

Study appraisal and synthesis methods

Two authors independently reviewed the abstracts and full articles. The FNR and factors associated with FNR were synthesized through random-effects meta-analyses and meta-regression.

The results

We identified 62 eligible studies. The overall FNR for the 62 articles was 4% (95% CL 3-5).There was no significant difference in the FNR in patients with high-risk endometrial cancer compared to patients with low-risk endometrial cancer. There was no difference in the FNR for whether frozen sections were used intraoperatively. The type of dye used intraoperatively (indocyanine green/blue dye) were not significantly associated with the false negative rate. Cervical injection reduced the FNR compared with alternative injection techniques. Indocyanine green reduced the FNR compared with alternative Tc-99m. Postoperative pathologic ultrastaging reduced the FNR.

Conclusions

Alternative injection techniques (other than the cervix), Tc-99m dye tracer, and the absence of postoperative pathologic ultrastaging are risk factors for a high FNR in endometrial cancer patients who undergo SLNB; therefore, we should be vigilant for missed diagnosis of metastatic lymph nodes after SLNB in such populations.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023433637.

Sentinel Lymph Nodes and Precision Surgery in Gynecologic Cancer

Besides histologic features, the presence of nodal metastasis is the most crucial prognostic factor for recurrence and survival for patients with gynecologic cancer. Conventionally, lymphadenectomy has been performed routinely to assess lymphatic metastasis. However, lymphadenectomy may be unnecessary in early-stage gynecologic cancer, because the percentage of patients with lymph node involvement is very low. The recent use of sentinel lymph node mapping has provided high feasibility, safety, and accuracy in the assessment of nodal metastasis. The National Comprehensive Cancer Network Clinical Practice Guidelines have incorporated the sentinel lymph node for nodal evaluation in vulvar, endometrial, and cervical cancers.

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.

Relevance of sentinel lymph node biopsy in early endometrial cancer: A series of 249 cases

OBJECTIVE

We aimed to evaluate the impact of the sentinel lymph node (SLN) biopsy on adjuvant therapy, recurrence and survival in early endometrial cancer (EC).

STUDY DESIGN

We retrospectively included all patients who underwent SLN biopsy for EC between February 2007 and March 2018.

RESULTS

Of the 249 EC patients included, the overall SLN detection rate was 91 %. SLNs were positive in 36 (14.4 %) cases. Nine of the 13 preoperative low-risk patients with positive SLNs were re-operated and 22 % presented positive non-SLNs. No second surgery was required for the 10 patients upstaged to intermediate risk after negative SLN biopsy. Nine of the 11 preoperative intermediate-risk patients with positive SLNs were re-operated and 33 % presented positive non-SLNs. Eleven of the 24 preoperative high-risk patients with negative SLNs were re-operated and 27 % presented positive non-SLNs. For the whole population, 3-year overall survival was 99 % (CI 95 % (97-1)) and 3-year recurrence-free survival (RFS) was 92 % (CI 95 % (0.87-0.95)).

CONCLUSION

Our study supports the feasibility of the SLN procedure for assessing risk recurrence in patients with early-stage EC. SLN biopsy should lead to major reductions in secondary staging and better adaptation of adjuvant therapy.

The Reliability of Intraoperative Assessment on Predicting Tumor Size, Myometrial Invasion, and Cervical Involvement in Patients With a Preoperative Diagnosis of Complex Atypical Hyperplasia or (Clinical Stage I) Endometrial Cancer: A Prospective Cohort Study

OBJECTIVES

The objective of this study is to assess the reliability of intraoperative uterine assessment compared with the final pathologic evaluation in patients with endometrial cancer (EC) and whether assessment improves with experience.

METHODS

After Institutional Review Board approval, a prospective cohort study of women surgically managed with biopsy-proven complex atypical hyperplasia (CAH) or EC between March 2015 and December 2016 was performed. Demographics, preoperative biopsy results, procedure, intraoperative and final pathologic evaluation of lesion size, myometrial invasion, and lower uterine segment/cervical involvement were abstracted. The agreement between the intraoperative and final pathologic evaluation of tumor involvement of the uterus was determined using the kappa statistic and the intraclass correlation coefficient.

RESULTS

A total of 264 patients with a preoperative diagnosis of CAH or EC were included-71 (26.9%) with CAH and 193 (73.1%) with EC. The mean age was 62.6±11.5, and mean body mass index was 37.2±10.1. The majority of women were white (67%). A total of 227 (85.9%) patients underwent a laparoscopic or robotic hysterectomy, whereas 36 (13.6%) underwent an abdominal hysterectomy. 233 (88.3%) patients had EC and 21 (7.9%) patients had CAH on final pathology. There was a fair agreement between the intraoperative estimation of myometrial invasion (κ=0.37). A moderate agreement exists between the intraoperative estimation of lower uterine segment/cervical involvement (κ=0.57). There was a strong agreement between intraoperative tumor size assessment and the final path (intraclass correlation coefficient=0.74). The intraoperative correlation of tumor size was similar for the first half of the cohort (κ=0.50) and the second half (κ=0.46) chronologically.

CONCLUSIONS

Despite only a fair correlation in the myometrial invasion, intraoperative assessment of cervical involvement and especially tumor size is more readily identified and overall accurate. Therefore, intraoperative evaluation is an additional tool to use when making the decision to proceed with surgical staging.

[Lymph node management in endometrial cancer]

In 2018, around 382,100 new cases of endometrial cancer (EC) were reported worldwide, accounting for about 4.4% of all new cases of cancer in women. In France, in 2018, the EC is the first gynecological cancer in incidence and the fourth cancer in women. The rationale for the therapeutic management of EC is based on the estimation of a theoretical risk of recurrence and lymph node metastasis using MRI and preoperative biopsy criteria. However, lymph node status remains the determining factor of adjuvant treatment. In order to reduce the morbidity of lymphadenectomy, the concept of sentinel lymph node biopsy (SLN) has been developed. The SLN technique has evolved in recent years, thanks to the advent of robotics and the creation of fluorescence detection cameras. It has been shown that detection of SLN with Indocyanine Green (ICG) allows for more frequent bilateral migration of 88 to 100% and better detection of pelvic GS in 97% of cases with a decrease in morbidity. Recently, in view of the absence of a therapeutic role of lymph node staging, the operational risks and the delay of adjuvant treatments, in case of pelvic lymph node metastasis on definitive histological examination, the question of secondarily performing paraaortic lymphadenectomy arises. The SLN procedure, extended to all early-stage endometrial cancers, should lead to a major reduction in the use of secondary staging and better adaptation of adjuvant therapy.

Feasibility and optimal dosage of indocyanine green fluorescence for sentinel lymph node detection using robotic single-site instrumentation: preclinical study

The present study was performed to determine the optimal dosage of indocyanine green (ICG) to accurately differentiate the sentinel node from surrounding tissue and then to test this dosage using novel single-port robotic instrumentation. The study was performed in healthy female pigs. After induction of anesthesia, all pigs underwent exploratory laparotomy, dissection of the bladder, and colpotomy to reveal the cervical os. With use of a 21-gauge needle, 0.5 mL normal saline solution was injected at the 3- and 9-o'clock positions as control. Four concentrations of ICG were constituted for doses of 1000, 500, 250, and 175 μg per 0.5 mL. ICG was then injected at the 3- and 9-o'clock positions on the cervix. The SPY camera was used to track ICG into the sentinel nodes and to quantify the intensity of light emitted. SPY technology uses an intensity scale of 1 to 256; this scale was used to determine the difference in intensity between the sentinel node and surrounding tissues. The optimal dosage was tested using single-port robotic instrumentation with the same injection techniques. A sentinel node was identified at all doses except 175 μg, at which ICG stayed in the cervix and vasculature only. For both the 500- and 250-μg doses, the sentinel node was identified before reaching maximum intensity. At maximum intensity, the difference between the surrounding tissue and the node was 207 (251 vs 44) for the 500-μg dose and 159 (251 vs 92) for the 250-μg dose. Sentinel lymph node (SLN) biopsy was successfully performed using single-port robotic technology with both the 250- and 500-μg doses. For SLN detection, the dose of ICG is related to the ability to differentiate the sentinel node from the surrounding tissue. An ICG dose of 250 to 500 μg enables identification of a SLN with more distinction from the surrounding tissues, and this procedure is feasible using single-port robotics instrumentation.

An overview of uterine cancer and its management

Endometrial cancer is increasingly common in affluent Western countries, largely owing to the growing obesity of those populations. There are two recognized types of endometrial cancer: Type I is more common and is associated with obese postmenopausal women and comprises approximately 80% of all endometrial cancers; Type II describes a woman who is often younger and thinner with a more aggressive histologic type that is nonestrogen dependent, of either serous or clear cell histology, and consists of a more aggressive clinical course and results in poorer prognosis. As the majority of patients with endometrial cancer present with symptoms and have early disease, screening is unlikely to be cost effective or reduce the mortality rate. However, surveillance of high-risk populations is a different proposition. Patients who may benefit from routine surveillance include those with a family history of endometrial cancer, a history of hormone replacement therapy with less than 12-14 days of progestogens, long-term use of tamoxifen, hereditary nonpolyposis colorectal cancer family syndrome, Cowden's syndrome, Peutz-Jeghers syndrome, a history of breast cancer and obesity. Most patients with endometrial cancer are offered surgery as first-line therapy. The standard surgical procedure should be an extrafascial total hysterectomy with bilateral salpingo-oophorectomy. Adnexal removal is also recommended, even if the adnexa appear normal, as they may contain micrometastases. The safety of a laparoscopic approach in the surgical management of uterine cancer has not yet been demonstrated in prospective randomized trials, therefore, the field awaits the Gynaecologic Oncology Group's prospective Lap-2 study. While post-treatment follow-up guidelines vary between institutions and countries, in general, patients at high risk of recurrence are followed closely every 3-4 months for the first year or two, then every 6 months to complete 5 years of follow-up.

Controversies in the management of endometrial carcinoma: an update

Endometrial carcinoma is the commonest type of female genital tract malignancy in the developed countries. Endometrial carcinoma is usually confined to the uterus at the time of diagnosis and as such usually carries an excellent prognosis with high curability. Our understanding and management of endometrial cancer have continuously developed. Current controversies focus on screening and early detection, the extent of nodal surgery, and the changing roles of radiation therapy and chemotherapy and will be discussed in this paper.

[Current position of the sentinel lymph node procedure in endometrial cancer]

Lymph node status is a major prognostic element in endometrial cancer and affects the choice of adjuvant therapy. The sentinel lymph node (SLN) procedure is proposed as an alternative to lymphadenectomy. This review aims to assess its feasibility. To this end, 19 studies have been analysed. It appears that double detection (colorimetric and isotopic) is better than single detection, independent of injection site. Hysteroscopic injection is technically more difficult, yet can be done near the tumoral lesion. The cervical site does not accurately reflect the lymphatic drainage of the uterine body but is easier to access. SLN detection rate is notably identical between these two injections sites. Lomboaortic detection rate is lower for cervical injections than for endometrial ones. The myometrial site is also difficult to access (intraoperatively), due to same limitations as the hysteroscopic route, and can be deceiving (insufficient detection rate and high false-negative rate). The SLN allows for ultrastadification (micrometastases and isolated tumoral cells) with the development of new pathological techniques (serial sections and immunohistochemistry). Data on SLN in endometrial cancer is very heterogeneous in terms of methodology and populations studied. Despite being well-known, the SLN procedure in endometrial cancer remains in its feasibility stage. Its place in therapeutic strategies needs to be further explored and its potential benefit remains to be confirmed.

[Sentinel lymph node procedure and uterine cancers]

Lymph node metastases in cervical and endometrial cancer are major prognostic factors. Lymph-nodal involvement determines adjuvant therapy. As imagery is not reliable to diagnose lymph node status, pelvic +/- para-aortic lymphadenectomy remains the gold standard. These surgical procedures are, however, responsible for specific morbidity: lymphocele and lymphedema. Sentinel lymph node procedure could avoid lymphadenectomy and their complications in cervical and endometrial cancer with good negative predictive values. We present actual indications, procedure and results of sentinel lymph node procedures in cervical and endometrial cancer.

[Role of laparoscopy in the treatment of early endometrial cancer]

Endometrial cancer is the most frequent malignant tumor of the female genital tract. Traditionally, surgical treatment is performed via laparotomy, but laparoscopy has recently gained wider acceptance. Data regarding survival and recurrence are comparable in case of laparotomy or laparoscopy. Surgical morbidity and postoperative recovery time are significantly lower by laparoscopy. In case of early endometrial cancer laparoscopy is an invaluable alternative method of choice but it has to be performed by skilled laparoscopic surgeons. Authors review the current literature regarding the role of laparoscopy in the treatment of early stage endometrial cancer.

Controversies in surgical staging of endometrial cancer

Endometrial cancer is the most common gynaecological malignancy and its incidence is increasing. In 1998, international federation of gynaecologists and obstetricians (FIGO) required a change from clinical to surgical staging in endometrial cancer, introducing pelvic and paraaortic lymphadenectomy. This staging requirement raised controversies around the importance of determining nodal status and impact of lymphadenectomy on outcomes. There is agreement about the prognostic value of lymphadenectomy, but its extent, therapeutic value, and benefits in terms of survival are still matter of debate, especially in early stages. Accurate preoperative risk stratification can guide to the appropriate type of surgery by selecting patients who benefit of lymphadenectomy. However, available preoperative and intraoperative investigations are not highly accurate methods to detect lymph nodes and a complete surgical staging remains the most precise method to evaluate extrauterine spread of the disease. Laparotomy has always been considered the standard approach for endometrial cancer surgical staging. Traditional and robotic-assisted laparoscopic techniques seem to provide equivalent results in terms of disease-free survival and overall survival compared to laparotomy. These minimally invasive approaches demonstrated additional benefits as shorter hospital stay, less use of pain killers, lower rate of complications and improved quality of life.

Intraoperative sentinel lymph node detection by vital dye through laparoscopy or laparotomy in early endometrial cancer

BACKGROUND AND OBJECTIVES

Recent studies reported the feasibility of intraoperative lymphatic mapping in women with endometrial cancer but none of these studies compared the sentinel lymph nodes (SLNs) detection rates obtainable through laparoscopy or laparotomy. The purpose of this study was to address this issue.

METHODS

Thirty-four patients with clinical stage I-II endometrial cancer were enrolled in this prospective comparative trial. Four milliliters of Patent Blue Violet were injected into the cervix after the induction of general anesthesia. The assessment of SLNs was done in 17 patients through laparoscopy and in 17 patients through laparotomy as first step of systematic pelvic lymphadenectomy. Both SLNs and non-SLNs were evaluated for micrometastases.

RESULTS

The SLNs detection rate was significantly higher (82%) for laparoscopy than for laparotomy (41%; P = 0.008). Pelvic lymph node metastases were present in 6 out of 34 patients (18%) but only 3 (50%) of these patients were correctly identified.

CONCLUSIONS

SLNs detection rate is significantly higher through laparoscopy than through laparotomy after vital dye pericervical injection but intraoperative vital dye pericervical injection is not reliable as part of standard care for predicting lymphatic spread in women with early stage endometrial cancer.

Analysis of dendritic cells in sentinel lymph nodes of patients with endometrial and patients with cervical cancers

OBJECTIVE

The aim of this study was to identify the immune response in sentinel lymph nodes (SLNs) of patients with endometrial and patients with cervical cancers by analyzing the number of S-100-, CD1a-, CD83-positive (+) dendritic cells that are the major antigen-presenting cells.

METHODS

A total of 56 patients with early-stage cancer (n = 32, with cervical; n = 24, with endometrial cancer) underwent SLN biopsy. Sentinel lymph nodes and non-SLNs were stained with antibodies against S-100, CD1a, and CD83 as markers for dendritic cells to find out whether SLNs were immunomodulated compared with non-SLNs.

RESULTS

The mean values of S-100(+) and CD1a(+) dendritic cells in both the tumor-free and the metastatic SLNs were significantly higher than those of both the tumor-free and the metastatic non-SLNs. When metastatic SLNs were compared with nonmetastatic SLNs, CD83(+) dendritic cells were found significantly more abundant in nonmetastatic SLNs.

CONCLUSIONS

Significantly higher numbers of S-100(+) and CD1a(+) dendritic cells in the SLNs compared with those in the non-SLNs may indicate that SLNs are the first sites of immunostimulation. Immunosupression may be the underlying factor for the metastatic involvement of SLNs, which might be secondary to the significantly decreased number of mature dendritic cells in metastatic SLNs compared with tumor-free SLNs.

Sentinel lymph node mapping for grade 1 endometrial cancer: is it the answer to the surgical staging dilemma?

OBJECTIVE

To describe the accuracy of SLN mapping in patients with a preoperative diagnosis of grade 1 endometrial cancer.

METHODS

A prospective, non-randomized study of women with a preoperative diagnosis of endometrial cancer and clinical stage I disease was conducted. A subset analysis of patients with a preoperative diagnosis of grade 1 endometrial endometrioid cancer was performed. All patients had preoperative lymphoscintigraphy with Tc99m on the day of or day before surgery followed by an intraoperative injection of 2 cm(3) of isosulfan or methylene blue dye deep into the cervix or both cervix and fundus. All patients underwent hysterectomy, bilateral salpingo-oophorectomy, and regional nodal dissection. Hot and/or blue nodes were labeled as SLNs and sent for histopathological analysis.

RESULTS

Forty-two patients with a preoperative diagnosis of grade 1 endometrial carcinoma treated from 3/06 to 8/08 were identified. Twenty-five (60%) had laparoscopic surgery; 17 (40%) were treated by laparotomy. Preoperative lymphoscintigraphy visualized SLNs in 30 patients (71%); intraoperative localization of the SLN was possible in 36 patients (86%). A median of 3 SLNs (range, 1-14) and 14.5 non-SLNs (range, 4-55) were examined. In all, 4/36 (11%) had positive SLNs-3 seen on H&E and 1 as cytokeratin-positive cells on IHC. All node-positive cases were picked up by the SLN; there were no false-negative cases. The sensitivity of the SLN procedure in the 36 patients who had an SLN identified was 100%.

CONCLUSION

Sentinel lymph node mapping using a cervical injection with combined Tc and blue dye is feasible and accurate in patients with grade 1 endometrial cancer and may be a reasonable option for this select group of patients. Regional lymphadenectomy remains the gold standard in many practices, particularly for the approximately 15% of cases with failed SLN mapping.

Lymphatic Mapping in Endometrial Cancer: Comparison of Hysteroscopic and Subserosal Injection and the Distribution of Sentinel Lymph Nodes

Introduction:

Endometrial cancer incidence increases over the age of 65 and lymphadenectomy in these women is a morbid procedure. Sentinel lymph node (SLN) should avoid extensive lymphadenectomy in node negative patients. The aim of this prospective study is to determine the feasibility and usefulness of lymphatic mapping and SLN identification in the management of endometrial cancer.

Methods:

From January 2004 to December 2007 101 women with endometrial cancer participated in the study. We injected 99Tc hysteroscopically, peritumorally 2 hours before laparotomy in 24 women. We applied 99Tc and blue dye subserously after laparotomy and before adhesiolysis in 67 women. Ten patients with metastatic disease in ovary, omentum, peritoneum, and bulky nodes were excluded from analysis.

Results:

We detected SLN in 12 women (50%) in hysteroscopic group and in 49 women (73.1%) in subserous group. We identified 133 SLNs in 61 women. We found 20 SLNs (15.0%) in supraobturator region, 78 (58.6%) in external iliac area, 11 (8.3%) in paraaortal area, 13 (9.8%) on common iliac artery, 8 (6.0%) in medial part of lateral parametrium, and 3 (2.3%) in presacral area.

Conclusions:

Sentinel lymph node identification is a new strategy that can be used to examine nodal status with a high successful rate in breast, cervical, and vulvar cancer. Results in endometrial cancer are not as successful, however. In the future, it will be necessary to find optimal timing, the best route of application, and the "right" size of the 99mTc particles. Subserous application seems to be superior to hysteroscopic application.

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology.

Limits of lymphoscintigraphy for sentinel node biopsy in women with endometrial cancer

OBJECTIVE

Lymph node status in endometrial cancer is a major prognostic factor. Sentinel lymph node (SLN) biopsy using radiocolloid and blue dye labeling has emerged as an alternative to systematic lymphadenectomy. This technique requires a preoperative lymphoscintigraphy. The aim of this study was to evaluate the limits of day-before preoperative lymphoscintigraphy to SLN biopsy.

METHODS

Between July 2002 and March 2007, 38 patients with endometrial cancer underwent laparoscopic SLN procedure using radiocolloid and blue dye. Those with early-stage I endometrial cancer (35 patients) underwent a SLN procedure followed by systematic pelvic lymphadenectomy and a hysterectomy with bilateral salpingo-oophorectomy while those with presumed stage IIB on MR imaging (3 patients) underwent a radical hysterectomy. Omentectomy and paraaortic lymphadenectomy were also performed for women with clear cell or serous papillary carcinoma (5 patients). The SLN identification rates and false-negative rates were studied.

RESULTS

The detection rate of lymphoscintigraphy was 84.5% (32/38), with 1.9 nodes per patient. Eight of 17 patients (47%) with unilateral sentinel lymph node on lymphoscintigraphy had bilateral SLNs at surgery and three of 15 patients (20%) with bilateral SLN on lymphoscintigraphy had unilateral SLN at surgery. The correlation was poor (kappa=0.266). When categorized in <2 and > or =2 sentinel nodes, the correlation between lymphoscintigraphic and surgical SLN mapping was moderate (kappa=0.33).

CONCLUSION

Our results demonstrated the low correlation between day-before lymphoscintigraphy and surgical SLN mapping raising issues of its usefulness and cost-effectiveness in routine practice.

Lymphatic mapping in endometrial cancer: a literature review of current techniques and results

The objective of this study was to review available literature pertaining to lymphatic mapping in endometrial cancer. We reviewed all published series of lymphatic mapping in endometrial cancer available through a PubMed search. Techniques used for identification of sentinel lymph nodes fell into three main categories in relation to the site of injection: 1) uterine subserosal, 2) cervical, and 3) endometrial via hysteroscopy. High detection rates may be achieved in all three categories. The use of both radiolabeled technetium and blue dye has been reported. A combination of cervical and uterine corpus injections appears feasible and less technically demanding than hysteroscopic injections. Immunohistochemistry staining of sentinel nodes coupled with step-serial section may improve the detection of micrometastasis in sentinel nodes. Meaningful sensitivity and false-negative rates cannot be calculated from current series due to their small numbers. The role of lymphatic mapping in endometrial carcinoma and the optimal injection site remains to be determined. A combination of cervical and uterine fundal injections may result in acceptable detection rates. Large-scale validation trials requiring complete pelvic and para-aortic lymphadenectomy are needed to evaluate its role in future clinical practice.

The lateral infraureteral parametrium: myth or reality?

OBJECTIVE

The objective of the study was to describe the surgical anatomy of infraureteral parametrium.

STUDY DESIGN

Findings of laparoscopic dissections during 12 type III radical hysterectomies were compared with findings obtained by bilateral pelvic dissections of 5 fresh and 5 embalmed female cadavers and to magnetic resonance imaging of 10 healthy controls.

RESULTS

Two anatomical entities of the parametrium were distinguished: (1) the lateral mesometrium corresponding to the blade containing vessels and lymph nodes of the uterus; and (2) the infraureteral parametrium extending dorsally from cervix and vagina. The lateral paracervix classically described under the ureter was never identified. Infraureteral parametrium appeared as a fibrous tissue extending in a lateral, dorsal, and caudal direction on both sides of the rectum and very close to the pelvic plexus.

CONCLUSION

Our results attest to the absence of infraureteral parametrium, raising the issue of the surgical relevance of radical hysterectomy classification and the redefinition of the concept of radical hysterectomy.

Techniques of sentinel lymph node identification for early-stage cervical and uterine cancer

Techniques for sentinel lymph node injections have varied over the years in both cervical and uterine malignancy lymph node mapping. There remains considerable variation in techniques, particularly for uterine malignancies. This review summarizes some of the techniques that have been published and are currently utilized in sentinel lymph node mapping for cervical and uterine malignancies.

Current and future surgical approaches in the management of endometrial carcinoma

The surgical approach to endometrial carcinoma has been and continues to be inconsistent. It ranges from hysterectomy alone for all patients, hysterectomy with lymphadenectomy based on the surgeon’s criteria for risk of nodal metastasis based on preoperative grading and/or intraoperative assessments, and hysterectomy with limited lymphadenectomy, to hysterectomy with full pelvic and para-aortic lymphadenectomy for all patients. Recent evidence has clearly described the very poor correlation of pre- and/or intraoperative assessments with final hysterectomy pathologic findings. Lymphadenectomy has also been found to be therapeutic in high-risk groups. Despite this, many surgeons have not adopted a policy of comprehensive staging for all patients with endometrial carcinoma. All patients with endometrial carcinoma diagnosed on preoperative endometrial sampling should undergo comprehensive surgical staging if technically and medically possible. Surgical cytoreduction of metastatic disease is also associated with improved outcomes.

The sentinel node concept in endometrial cancer: histopathologic validation by serial section and immunohistochemistry

BACKGROUND

The sentinel node (SN) is defined as the first node in the lymphatic system that drains a tumor site. If the SN is not metastatic, then all other nodes should also be disease-free. We used serial sections and immunohistochemical (IHC) staining to examine both SN and non-sentinel nodes (non-SNs).

PATIENTS AND METHODS

Twenty-three patients (median age 69 years) with early endometrial cancer underwent a laparoscopic SN procedure based on a combined detection method, followed by complete laparoscopic pelvic lymphadenectomy. If the SN was free of metastasis by both hematoxylin and eosin (H&E) and IHC staining, all non-SNs were also examined by the combined staining method.

RESULTS

SNs were identified in 19 patients (82.6%). A total of 47 SNs were removed (mean 2.5). Ten SNs (21.3%) from five patients (26.3%) were found to be metastatic at the final histologic assessment. In 14 patients, no metastatic SN involvement was detected by H&E and IHC staining. In these 14 patients, 120 non-SNs were examined by serial sectioning and IHC, and none were found to be metastatic.

CONCLUSION

The SN procedure appears to reliably predict the metastatic status of the regional lymphatic basin in patients with early endometrial cancer.

La recherche du ganglion sentinelle dans le cancer de l'endomètre a-t-elle un intérêt?

In cancer research, regional lymph node status is a major prognostic factor and a decision criterion for adjuvant therapy. The sentinel node procedure, which has emerged to reduce morbidity of extensive lymphadenectomy, remains a major step in the surgical management of various cancers. Sentinel node procedure has become a standard technique for the determination of the nodal stage of the disease in patients with melanoma, vulvar cancer and in breast cancer. In endometrial cancer, the sentinel node biopsy is still at the stage of feasibility. In this article, we review the technical aspects, results, clinical implications and limitations of sentinel node procedure in endometrial cancers.

A new approach to label sentinel nodes in endometrial cancer

PURPOSE

The objective of the study was to determine the feasibility of a new method of labeling sentinel lymph nodes in patients with endometrial cancer using blue dye.

PATIENTS AND METHODS

4 ml of blue dye was subserously administered in 25 patients with endometrial cancer at eight sites. After 8 min, sentinel lymph nodes were harvested.

RESULTS

Detection rate was 92.0%, sensitivity was 62.5%, and negative predictive value was 92.5%. In two patients there was no detection of sentinel nodes and in addition in two patients only sentinel nodes were harvested due to minimal disease. No side effects occurred.

CONCLUSIONS

This new and simple approach yielded a high pelvic detection rate. This new approach reveals a way to label sentinel nodes in endometrial cancer. Combining a different labeling agent with the proposed new method might overcome the lack of para-aortic sentinel detection.

Detection of micrometastases in the sentinel lymph nodes of patients with endometrial cancer

OBJECTIVE

We investigated the utility of sentinel lymph node (SLN) mapping for the detection of endometrial carcinoma micrometastases. We reevaluated the accuracy of our SLN detection procedure, this time combining step-serial section with cytokeratin immunostaining.

PATIENTS AND METHODS

Between March 2002 and March 2005, consecutive patients undergoing laparotomy (total abdominal hysterectomy, bilateral salpingo-oophorectomy, total pelvic lymphadenectomy and para-aortic lymphadenectomy to the level of renal veins) with SLN biopsy for endometrial cancer at Tohoku University Hospital were enrolled in this study. Excluded were patients in whom lymph node metastases were detected by routine histological examination or those without detectable SLNs. All surgically removed lymph nodes, including SLNs, were examined histopathologically by immunohistochemistry staining with an anti-cytokeratin antibody (AE1/AE3) combined with step-serial sectioning at 200-500 microm intervals.

RESULTS

Four of seventy-four SLNs (5%) obtained from 20 patients had micrometastases or isolated tumor cells (ITC). In contrast, only 4 of the 1350 non-SLNs obtained from 20 patients (0.3%) had detectable micrometastases. The micrometastases were detected in the external iliac basin (two cases) and in the para-aortic area (two cases). The isolated tumor cell was detected in the external iliac basin (one case).

CONCLUSION

SLNs detected by our method had micrometastases more frequently than did non-SLNs. Easy detection of micrometastases by immunostaining is only possible with step-serial sectioning of the SLNs.

Laparoscopic surgery in gynaecological oncology

AIMS

The use of laparoscopic staging and/or surgery in the field of gynaecological oncology was pioneered in the late 1980s and the first reports were published in the early 1990s. The issue has been initially most controversial, and is still debated, with some justification considering the possible adverse consequences of surgical mismanagement of gynaecologic malignancy.

METHODS

The current literature has been reviewed and updated, concentrating on long-term, and/or comparative studies. Large observational studies have also been included. Recent papers concerning new developments have been selected.

FINDINGS

A number of papers have confirmed the absence of significant adverse effects on survival after laparoscopic diagnosis or surgery in gynaecological cancers. New developments cover virtually all the basic techniques in cancer surgery, including major exenterative surgery. The use of extraperitoneal technique for aortic dissections is emerging as a new tool. New indications, such as radical vaginal trachelectomy, radical parametrectomy, pelvic sentinel node identification, interval debulking surgery of adnexal malignancies, or the use of pretherapeutic surgical staging of uterine cancers, have been developed in direct relation with the use of laparoscopic techniques.

CONCLUSIONS

Current available data and worldwide interest clearly demonstrate that laparoscopic techniques must now be part of the armamentarium of the gynaecologic oncologist. Postoperative morbidity and recurrence risk do not seem to be affected. Cost-efficiency of laparoscopic procedures is based on the reduction of hospital stay and recovery time, although operating room time is increased in some procedures. Combined training in gynaecologic oncology and in laparoscopic and/or vaginal surgery is more than ever mandatory to avoid the risk of inadequate staging or management of pelvic malignancies.

[Is sentinel node biopsy feasible in endometrial cancer? Results in 26 patients]

OBJECTIVES

To evaluate detection rate, topography and false negatives of sentinel lymph node in endometrial cancer.

MATERIAL AND METHODS

Twenty-six patients were included. Lymphoscintigraphy was performed the day before surgery. Preoperative detection of the sentinel lymph node was performed with cervical blue dye injection and a gamma probe. Separate pathology examinations were performed for sentinel and non-sentinel lymph nodes. Sentinel lymph nodes were examined with hematoxylin-eosin-safran stain, and immunohistochemistry if negative.

RESULTS

Twenty-six patients had a positive lymphoscintigraphy. Preoperative detection was successful in 21 patients (80.8%): the detection rate with isotopic method, 19 cases (73.1%), was superior to the dye detection, 15 cases (57.7%). No isolated lombo-aortic sentinel lymph nodes were observed, and all sentinel lymph nodes were in the ilio-obturator region. Seven patients presented lymphatic spread, and 4 of them had at least one sentinel node. There was one micrometastasis in sentinel node, associated with isolated tumoral cells in pelvic lymphadenectomy. There was no false negative of sentinel node.

CONCLUSION

The biopsy of sentinel lymph node is a feasible procedure in endometrial cancer. There was one micrometastatic sentinel node. However there was no isolated lomboaortic sentinel lymph node in this study.

The sentinel node in gynaecological malignancies

As lymph node metastasis is one of the earliest features of tumour cell spread in most human cancers, assessment of the regional lymph nodes is required for tumour staging, determining prognosis and planning adjuvant therapeutic strategies. However, complete lymph node dissections are frequently associated with significant complications. Conjugating the diagnostic advantages with decreased morbidity, the sentinel node concept represents one of the most recent advances in surgical oncology. In this review we briefly highlight the historical background of the development of the sentinel node concept, the anatomical evidence for applying the sentinel node concept in pelvic gynaecological cancers and the technical aspects of sentinel node detection. We discuss recent studies in vulval, cervical and endometrial cancer.

Sentinel Node Mapping With Isosulfan Blue Dye in Endometrial Cancer

OBJECTIVE

To determine the feasibility of sentinel node mapping in endometrial cancer using hysteroscopic injection of isosulfan blue dye.

METHODS

Sixteen patients with endometrial cancer were enrolled in this pilot study. Hysteroscopy was performed at laparotomy to locate the tumour. Isosulfan blue dye was injected into the endomyometrium around the tumour by hysteroscopy, into the serosa overlying the tumour, or both. Blue lymph nodes were removed as sentinel nodes. Pelvic lymphadenectomy, total abdominal hysterectomy, and bilateral salpingo-oophorectomy were then performed.

RESULTS

Dye uptake into lymphatics occurred in 13 of the 16 cases (81%). Blue lymph nodes were identified in five cases with serosal injection alone (56%) and in two cases with combined serosal and hysteroscopic injection (50%). No blue lymph nodes were identified with hysteroscopic injection alone. The overall sentinel node identification rate was 44%, and the negative predictive value was 86%.

CONCLUSION

Although the concept of sentinel node mapping in endometrial cancer is appealing, the technique of hysteroscopic injection of isosulfan blue dye alone had minimal success in this study. Alternative methods should be explored.

Sentinel lymph node detection following the hysteroscopic peritumoural injection of 99mTc-labelled albumin nanocolloid in endometrial cancer

PURPOSE

The purpose of this study was to assess the feasibility of sentinel lymph node (SLN) detection in endometrial cancer patients with a dual-tracer procedure after hysteroscopic peritumoural injection.

METHODS

Twenty-six women with previously untreated endometrial adenocarcinoma underwent the hysteroscopic injection of 111 MBq 99mTc-Nanocoll and blue dye administered subendometrially around the lesion. On the same day, all 26 patients underwent lymphoscintigraphy, followed 3-4 h later by hysterotomy with bilateral salpingo-oophorectomy and pelvic lymphadenectomy. Para-aortic lymphadenectomy was also performed in cases of either serous or papillary carcinoma (n=7/26). All SLNs were removed and examined with haematoxylin and eosin staining and immunohistochemical techniques.

RESULTS

The procedure was well tolerated by patients, only two experiencing transient vagal symptoms. The sensitivity of this technique for correct identification of SLNs was 100%. Lymph node metastases were found in 4 out of the 26 patients (15%), bilaterally in the external iliac region (n=1), unilaterally in the external iliac region (n=1), unilaterally in the common iliac region (n=1) and unilaterally in the para-aortic region (n=1). In all four cases, nodal metastases were located within SLNs detected by lymphoscintigraphy. Only 10 of the 26 patients (38%) had significant blue dye staining. All blue-stained SLNs were radioactive.

CONCLUSION

In patients with endometrial cancer, it is feasible to use lymphatic mapping and SLN biopsy to define the topographic distribution of the lymphatic network and also to accurately detect lumbo-aortic and pelvic metastases within SLNs. In the majority of patients with early stage endometrial cancer, this procedure may avoid unnecessary radical pelvic lymphadenectomy. It may also guide para-aortic lymph node dissection on the basis of the SLN status.