Validation and application of the sentinel lymph node concept in malignant vulvar tumours

Value of sentinel node ultrastaging and pathologic techniques in tumoral detection

PURPOSE OF REVIEW

Sentinel lymph node assessment is an option for patients with clinically early-stage vulvar cancer, endometrial cancer, cervical cancer, and, more recently, ovarian cancer. However, although ultrastaging is mandatory as part of the node evaluation, universally accepted pathology protocols are lacking. This review focuses on the current evidence for the most relevant aspects of sentinel lymph node evaluation, as well as some controversial topics like frozen section or one-step nucleic acid amplification.

RECENT FINDINGS

The diagnostic accuracy of sentinel lymph node detection algorithms for patients with gynecologic neoplasms is high. However, the heterogeneity among the published studies and the absence of clear recommendations from most guidelines make it challenging to recommend one protocol over another. The minimum requirement from ultrastaging protocols (regarding the number of levels to be assessed, among others) to get the highest accuracy with a minor cost is unknown.

SUMMARY

Sentinel lymph node evaluation is now part of the surgical management for most early-stage gynecologic neoplasms. However, a universally accepted ultrastaging pathology protocol is lacking in literature and clinical practice. This gap requires significant effort from the gynecologic oncology and pathology community to be closed and then to allow advancements in surgical management for early-stage gynecologic tumors to go forward.

Multidisciplinary radio-guided surgery team: Alternative to change the current paradigm

INTRODUCTION

Given the constant increase in the healthcare demand for examinations related to radio-guided surgery (RGS), our hospital adopted new professional profiles in the RGS team, in order to partially reduce the time spent by nuclear medicine physicians on this task.

AIM

To analyze the process of incorporating the profiles of Diagnostic Imaging Technician (DIT) and Sentinel Node Referent Nurse (SNRN), evaluating their deployment in the procedures linked to the technique.

MATERIAL AND METHODS

Analysis of RGS activity during the period 2018-2022, focusing on pre-surgical and surgical procedures related to breast cancer (BC) and malignant melanoma (MM), as they are those pathologies on which the transfer of care competencies was concentrated. Chronological evolution of the competencies assumed by the different profiles during their integration into the RGS team.

RESULTS

RGS's healthcare activity during the analyzed period experienced an increase of 109%. BC and MM were the pathologies that accounted for by far the greatest demand for care. The transfer of competencies in these two pathologies occurred in a progressive and staggered manner, with 74% (460/622) of the administration phase being carried out by the SNRN and 64% (333/519) of the surgeries by the DIT in 2022.

CONCLUSIONS

The creation of a multidisciplinary RGS team that includes different professional profiles (nuclear medicine physician [MN], ERGC and TSID) is an effective strategy to respond to the increase in the complexity and number of all procedures related to RGS.

Should video laryngoscopy or direct laryngoscopy be used for adults undergoing endotracheal intubation in the pre-hospital setting? A critical appraisal of a systematic review

The safety and utility of endotracheal intubation by paramedics in the United Kingdom is a matter of debate. Considering the controversy surrounding the safety of paramedic-performed endotracheal intubation, any interventions that enhance patient safety should be evaluated for implementation based on solid evidence of their effectiveness. A systematic review performed by Hansel and colleagues (2022) sought to assess compare video laryngoscopes against direct laryngoscopes in clinical practice. This commentary aims to critically appraise the methods used within the review by Hansel et al (2022) and expand upon the findings in the context of clinical practice.

Vulvar squamous cell carcinoma arising on human papillomavirus-independent precursors mimicking high-grade squamous intra-epithelial lesion: a distinct and highly recurrent subtype of vulvar cancer

AIMS

Each category of vulvar squamous cell carcinoma (VSCC), human papillomavirus (HPV)-associated and HPV-independent, arises on a specific intra-epithelial precursor: high-grade squamous intra-epithelial lesions (HSIL) and differentiated vulvar intra-epithelial neoplasia (dVIN), respectively. However, a subset of HPV-independent VSCC arises on an intra-epithelial precursor closely mimicking HSIL. We aimed to explore the clinicopathological features of the HPV-independent tumours with HSIL-like lesions and compare them with HPV-independent VSCC with dVIN and HPV-associated tumours with HSIL.

METHODS AND RESULTS

We retrospectively identified 105 cases of surgically treated VSCC with adjacent intra-epithelial precursors. The cases were classified into three groups based on the HPV status and the adjacent precursor identified: (i) HPV-associated VSCC with HSIL (n = 26), (ii) HPV-independent VSCC with dVIN lesions (n = 54) and (iii) HPV-independent VSCC with HSIL-like lesions (n = 25). We analysed the histological and clinical features including the recurrence-free survival and disease-specific survival in the three groups. Patients with HPV-independent VSCC with HSIL-like lesions and with dVIN were older than patients with HPV-associated VSCC (76 and 77 versus 66 years, respectively, P < 0.001). HPV-independent VSCC with HSIL-like lesions recurred more frequently [hazard ratio (HR) = 3.87; P < 0.001] than HPV-independent VSCC with dVIN (HR = 2.27; P = 0.1) and HPV-associated VSCC (HR = 1). In the multivariate analysis, HPV-independent VSCC with HSIL-like lesions remained significant for recurrence. No differences in disease-specific survival were observed between the three groups.

CONCLUSIONS

Even though VSCC with HSIL-like lesions are not associated with higher mortality, they are more likely to recur and might benefit from more intensive treatment strategies and closer surveillance after treatment.

Lymphatic mapping and sentinel node biopsy in vulvar melanoma: the first multicenter study and systematic review

OBJECTIVE

This multicenter study aimed to investigate the role of preoperative lymphatic mapping and sentinel node biopsy (SNB) as well as the impact of negative SNB on loco-regional control and survival in vulvar melanoma patients with clinically negative nodes (cN0).

METHODS

Patients who had a proven vulvar melanoma with a Breslow thickness of 1-4 mm, cN0 and underwent a preoperative lymphatic mapping followed by SNB between July 2013 and March 2021 were retrospectively included. Groin recurrence and mortality rate were calculated as absolute and relative frequency. Disease-free survival (DFS) and overall survival (OS) were assessed by the Kaplan-Meier method. We provided a systematic review, searching among PubMed/Medline and Embase libraries. A total of 6 studies were identified (48 patients).

RESULTS

A total of 18 women were included. Preoperative planar images showed 51 SNs in 28 groins. Additional SPECT/CT images were acquired in 5/18 cases; SNs were identified pre- and intra-operatively in all cases. A total of 65 SNs were excised from 28 groins. A total of 13/18 (72.2%) patients (21/28 groins, 75%) had negative SNs with no groin recurrences and 12/13 (92.3%) were still alive at last follow-up. Five out of the 18 (27.8%) patients (7/28 groins, 25%) had positive SNs, 2/5 (40%) patients died of cancer after 26.2 and 33.8 months, respectively. The median DFS and OS for the entire cohort were 17.9 months (95% CI, 10.3-19.9) and 65.0 months (95% CI, 26.2-infinite), respectively. The probability of DFS and OS at 3 years were 15.5% (95% CI, 2.6-38.7) and 64.3% (95% CI, 15.5-90.2), respectively.

CONCLUSIONS

The use of preoperative lymphatic mapping followed by SNB permits a precise and minimally invasive surgical approach in cN0 vulvar melanoma patients. Negative SNB is associated with low risk of groin relapse and good survival.

Sentinel lymphatic mapping for gynecologic malignancies

PURPOSE OF REVIEW

To summarize the latest data in Gynecologic Oncology for the use of sentinel lymphatic mapping in vulvar, uterine, and cervical cancers.

RECENT FINDINGS

To decrease morbidity and improve detection of lymphatic metastasis, lymphatic mapping with sentinel lymph node biopsy is emerging as standard of care over conventional systemic lymphadenectomy in the surgical management of gynecologic malignancies.

SUMMARY

Sentinel lymph node mapping with biopsy is one of the most significant advances in cancer surgery. The presence of nodal metastasis is not only a prognostic factor for recurrence and survival in patients with gynecologic malignancies, but also guides assessment for adjuvant treatment. This review article discusses the most recent clinical updates in sentinel lymph node mapping, dissection, and management in vulvar cancer, endometrial cancer, and cervical cancer.

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.

Gynaecological malignancies and sentinel lymph node mapping: an update

Assessment of pelvic, para-aortic or inguinal lymph nodes (LNs) provides not only important prognostic information, but also determines the need for adjuvant treatment. Sentinel lymph node (SLN) biopsy has the potential to provide this prognostic information, while reducing morbidity compared with extended LN dissection. This review discusses the clinical and pathological aspects of SLN biopsy in gynaecological cancer.

Sentinel lymph node biopsy procedure in squamous vulvar cancer. 10 years follow-up analysis

AIM

Application of sentinel lymph node biopsy (SLNB) procedure in early-stage vulvar cancer and analysis of results, recurrences and complications.

MATERIAL AND METHODS

40 patients with vulvar cancer and SLNB between 2008 and 2018 were retrospectively reviewed. During the surgical procedure the inguinofemoral lymph nodes were checked with a gamma probe to identify the sentinel nodes that were removed and referred for intraoperative pathological assessment. Subsequently, long-term patient follow-up was performed with analysis of complications, relapse and mortality.

RESULTS

40 patients (mean age: 72 years [47-86], the overall detection rate per patient was 95% and a total of 129 Sentinel Lymph Nodes (SLNs) were removed (3.22 SLN/patient). In 3 out of 25 patients with lateral tumour lesions drainage was bilateral and in 2 out of 15 with midline lesions drainage was unilateral. On lymphoscintigraphy, 16 out of 40 had bilateral drainage and 24 unilateral. A total of 119 SLN- and 10 SLN+ were obtained, in 8 out of 10 an inguinofemoral lymphadenectomy was performed. In the SLN- group, one case of lymphatic blockage and one false negative were included. In 12 out of 40 patients there were post-surgical complications, 4 of them lymphoedemas. In the median follow-up (40 months), 6 out of 10 with SLN+ (40% mortality) and 7 out of 30 SLN- (16% mortality) had recurrences.

CONCLUSIONS

SLNB in vulvar cancer is the technique of choice for correct staging and locoregional therapy. Correct clinical lymph node staging is important before surgery in order to avoid potential blockage drainages which could induce a false negative SLN.

Pathology of sentinel lymph nodes: historical perspective and current applications in gynecologic cancer

Efforts to reduce surgical morbidity related to en bloc lymph node removal associated with cancer surgery led to the development of targeted lymph node sampling to identify the lymph node(s) most likely to harbor a metastasis. Through identification of one or only a few lymph nodes at highest risk, the overall number of lymph nodes removed could be markedly reduced. Submission of fewer lymph nodes affords more detailed pathologic examination than would otherwise be practical with a standard lymph node dissection. Such enhanced pathologic examination techniques (ie, ultra-staging) have contributed to increased detection of lymph node metastases, primarily by detection of low volume metastatic disease. Based on the success of sentinel lymph node mapping and ultra-staging in breast cancer and melanoma, such techniques are increasingly used for other organ systems including the gynecologic tract. This review addresses the historical aspects of sentinel lymph node evaluation and reviews current ultra-staging protocols as well as the implications associated with increased detection of low volume metastases.

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

PURPOSE

This study aimed to update the clinical practice applications and technical procedures of sentinel lymph node (SLN) biopsy in vulvar cancer from European experts.

METHODS

A systematic data search using PubMed/MEDLINE database was performed up to May 29, 2019. Only original studies focused on SLN biopsy in vulvar cancer, published in the English language and with a minimum of nine patients were selected.

RESULTS

Among 280 citations, 65 studies fulfilled the inclusion criteria. On the basis of the published evidences and consensus of European experts, this study provides an updated overview on clinical applications and technical procedures of SLN biopsy in vulvar cancer.

CONCLUSIONS

SLN biopsy is nowadays the standard treatment for well-selected women with clinically negative lymph nodes. Negative SLN is associated with a low groin recurrence rate and a good 5-year disease-specific survival rate. SLN biopsy is the most cost-effective approach than lymphadenectomy in early-stage vulvar cancer. However, future trials should focus on the safe extension of the indication of SLN biopsy in vulvar cancer. Although radiotracers and optical agents are widely used in the clinical routine, there is an increasing interest for hybrid tracers like indocyanine-^99mTc-nanocolloid. Finally, it is essential to standardise the acquisition protocol including SPECT/CT images, and due to the low incidence of this type of malignancy to centralise this procedure in experienced centres for personalised approach.

Vulvar malignant melanoma: Pathogenesis, clinical behaviour and management: Review of the literature

Vulvar malignant melanoma (VMM) is a rare disease, accounting for 5% of all vulvar malignancies and is characterized by low survival and high recurrence rates. It is considered as a distinct entity of mucosal melanoma. Prognostic factors are higher age, advanced Breslow thickness, and lymph node involvement whilst central localization and ulceration status are still under debate. Surgery is the cornerstone for the treatment of primary VMM, however, it can be mutilating due to the anatomical location of the disease. Elective lymph node dissection is not part of standard care. The value of sentinel lymph node biopsy in VMM is still being studied. Radiation therapy and chemotherapy as adjuvant treatment do not benefit survival. Immunotherapy in cutaneous melanoma has shown promising results but clinical studies in VMM are scarce. In metastatic VMM, checkpoint inhibitors and in case of BRAF or KIT mutated metastatic VMM targeted therapy have shown clinical efficacy. In this review, we present an overview of clinical aspects, clinicopathological characteristics and its prognostic value and the latest view on (adjuvant) therapy and follow-up.

Long-term oncological outcomes of patients with negative sentinel lymph node in vulvar cancer. Comparative study with conventional lymphadenectomy

INTRODUCTION

The aim of this study was to compare oncological outcomes and morbidity in patients with early-stage vulvar cancer with negative sentinel lymph node (SLN) biopsy vs negative inguinofemoral lymphadenectomy (IFL).

MATERIAL AND METHODS

Study with retrospectively collected data in patients with squamous cell vulvar carcinomas ≤ 4 cm without suspected inguinofemoral lymph node metastases. Only patients with negative nodes after histopathology procedure were followed. Patients who underwent only SLN were compared with patients who underwent IFL ± SLN to compare recurrences, survival rates and morbidity.

RESULTS

Ninety-three patients were eligible for follow up: 42 with negative SLN and 51 with negative IFL ± SLN. The median follow-up period was 60.4 months (range 6.7-160.7). The rate of isolated first groin recurrence was 4.8% in patients with negative SLN and 2.0% in patients with negative IFL ± SLN (P = 0.587) and the rates of first isolated local recurrence were 28.6% and 31.4%, respectively (P = 0.823). Only 1 patient (2.4%) in the group of negative SLN had distant recurrence. The disease-specific survival rate at 5 years was 83.3% in the negative SLN group and 92.2% in the negative IFL ± SLN group (P = 0.214). We observed a higher rate of wound breakdown and infection after IFL than SLN biopsy (17.6% vs 10.6%; P = 0.020) and lymphedema (33.3% vs 0%; P < 0.001).

CONCLUSIONS

We report in the same population of patients with early-stage vulvar cancer that SLN biopsy does not have significantly higher rates of groin recurrences or lower survival rates compared with IFL. Moreover, the SLN procedure has less morbidity, which should encourage gynecologists to abandon IFL.

The sentinel node approach in gynaecological malignancies

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

The prognostic role of FIGO stage in patients with vulvar cancer: a systematic review and meta-analysis

OBJECTIVE

To perform a meta-analysis examining the survival of patients with vulvar cancer based on the 2009 International Federation of Gynecology and Obstetrics (FIGO) staging system.

METHODS

Medline, PubMed, and Cochrane databases were searched until 20 March 2015 for prospective or retrospective studies using the terms vulvar cancer, prognostic/prognosis, survival, recurrence, lymph nodes (LNs), inguinal lymphadenectomy/excision, and staging. The primary outcome was 5 year overall survival (OS), and secondary outcomes were 5 year disease-free survival (DFS) and progression-free survival (PFS).

RESULTS

Fourteen retrospective studies were included. The 5 year OS rate decreased with increasing 2009 FIGO stage and number of LN metastasis. FIGO stage I, II, III, and IV patients had 5 year OS rates of 84.0%, 74.6%, 47.8%, and 9.4%, respectively. Pooled estimates showed that the 5 year OS was 84.5% for patients without LN metastasis, and for patients with ≥3 LN metastases the 5 year OS rate was 30.1%. Similarly, the overall 5 year DFS and PFS decreased with the increasing number of LN metastases. The 5 year DFS rate was 87.2% for patients with no LN metastasis and for patients with ≥3 LN metastases was 35.4%. The 5 year PFS rate was 86.6% for patients with no LN metastasis and for patients with ≥3 LN metastases was 27.6%.

LIMITATIONS

All studies were retrospective studies. DFS and PFS rates in patients with different 2009 FIGO stages and with different mean tumor sizes were not examined due to a limited number of reports.

CONCLUSIONS

More advanced 2009 FIGO stage and greater number of LN metastases are associated with worse outcomes in patients with vulvar cancer.

Pathways of lymphatic spread in gynecologic malignancies

Precise radiologic evaluation of regional adenopathic involvement in pelvic gynecologic tumors is fundamental to clinical practice because of its prognostic and therapeutic significance. Likewise, the identification of metastatic adenopathies at posttreatment imaging is essential for assessing response and detecting recurrence. Similar to urologic neoplasms, gynecologic neoplasms most often spread regionally to the pelvic and retroperitoneal lymph nodes, following the normal drainage pathways of the pelvic organs. Familiarity with routes of dissemination, treatment options, and means of analyzing lymph node characteristics is crucial to determine the extent of disease. Two staging systems can be used in characterizing gynecologic malignancies: the FIGO (International Federation of Gynecology and Obstetrics) system, which is the most commonly and universally used, and the TNM (tumor, node, metastasis) system, which is based on clinical and/or pathologic classification. Anatomic assessment with multidetector computed tomography (CT) and magnetic resonance (MR) imaging is still the most commonly used technique for the detection of lymph node spread, which is mainly based on morphologic criteria, the most important of which is nodal size. However, size has limited diagnostic specificity. Consequently, functional imaging techniques such as diffusion-weighted MR imaging, positron emission tomography combined with CT, lymphoscintigraphy, and sentinel lymph node mapping, which are based on molecular and physiologic activity and allow more precise evaluation, are often incorporated into diagnostic imaging protocols for staging of gynecologic malignancies.

Sentinel node biopsy in vulvar cancer: Implications for staging

In 2008, the first Groningen International Study on Sentinel nodes in Vulvar cancer (GROINSS-V) showed that omission of inguinofemoral lymphadenectomy is safe in patients with early-stage vulvar cancer and a negative sentinel node and it simultaneously decreases treatment-related morbidity. An important part of the sentinel node procedure is pathologic ultrastaging of the removed sentinel nodes. Subsequently, since the introduction of this procedure in the standard care of patients with early-stage vulvar cancer, more and smaller inguinofemoral lymph node metastases have been diagnosed. The clinical consequences of these micrometastases are not clear yet. With increasing size of the sentinel node metastasis, chances of non-sentinel node metastases increase and those of survival decrease. The size of lymph node metastases is included in the latest staging system for vulvar cancer, however at this moment without clinical implications. Furthermore, a separate category for micrometastases is not incorporated yet. More research is needed to determine the clinical consequences of the size of (sentinel) lymph node metastases.

Sentinel node assessment for diagnosis of groin lymph node involvement in vulval cancer

BACKGROUND

Vulval cancer is usually treated by wide local excision with removal of groin lymph nodes (inguinofemoral lymphadenectomy) from one or both sides, depending on the tumour location. However, this procedure is associated with significant morbidity. As lymph node metastasis occurs in about 30% of women with early vulval cancer, accurate prediction of lymph node metastases could reduce the extent of surgery in many women, thereby reducing morbidity. Sentinel node assessment is a diagnostic technique that uses traceable agents to identify the spread of cancer cells to the lymph nodes draining affected tissue. Once the sentinel nodes are identified, they are removed and submitted to histological examination. This technique has been found to be useful in diagnosing the nodal involvement of other types of tumours. Sentinel node assessment in vulval cancer has been evaluated with various tracing agents. It is unclear which tracing agent or combination of agents is most accurate.

OBJECTIVES

To assess the diagnostic test accuracy of various techniques using traceable agents for sentinel lymph node assessment to diagnose groin lymph node metastasis in women with FIGO stage IB or higher vulval cancer and to investigate sources of heterogeneity.

SEARCH METHODS

We searched MEDLINE (1946 to February 2013), EMBASE (1974 to March 2013) and the relevant Cochrane trial registers.

SELECTION CRITERIA

Studies that evaluated the diagnostic accuracy of traceable agents for sentinel node assessment (involving the identification of a sentinel node plus histological examination) compared with histological examination of removed groin lymph nodes following complete inguinofemoral lymphadenectomy (IFL) in women with vulval cancer, provided there were sufficient data for the construction of two-by-two tables.

DATA COLLECTION AND ANALYSIS

Two authors (TAL, AP) 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 used univariate meta-analytical methods to estimate pooled sensitivity estimates.

MAIN RESULTS

We included 34 studies evaluating 1614 women and approximately 2396 groins. The overall methodological quality of included studies was moderate. The studies included in this review used the following traceable techniques to identify sentinel nodes in their participants: blue dye only (three studies), technetium only (eight studies), blue dye plus technetium combined (combined tests; 13 studies) and various inconsistent combinations of these three techniques (mixed tests; 10 studies). For studies of mixed tests, we obtained separate test data where possible.Most studies used haematoxylin and eosin (H&E) stains for the histological examination. Additionally an immunohistochemical (IHC) stain with and without ultrastaging was employed by 14 and eight studies, respectively. One study used reverse transcriptase polymerase chain reaction analysis (CA9 RT-PCR), whilst three studies did not describe the histological methods used.The pooled sensitivity estimate for studies using blue dye only was 0.94 (68 women; 95% confidence interval (CI) 0.69 to 0.99), for mixed tests was 0.91 (679 women; 95% CI 0.71 to 0.98), for technetium only was 0.93 (149 women; 95% CI 0.89 to 0.96) and for combined tests was 0.95 (390 women; 95% CI 0.89 to 0.97). Negative predictive values (NPVs) for all index tests were > 95%. Most studies also reported sentinel node detection rates (the ability of the test to identify a sentinel node) of the index test. The mean detection rate for blue dye alone was 82%, compared with 95%, 96% and 98% for mixed tests, technetium only and combined tests, respectively. We estimated the clinical consequences of the various tests for 100 women undergoing the sentinel node procedure, assuming the prevalence of groin metastases to be 30%. For the combined or technetium only tests, one and two women with groin metastases might be 'missed', respectively (95% CI 1 to 3); and for mixed tests, three women with groin metastases might be 'missed' (95% CI 1 to 9). The wide CIs associated with the pooled sensitivity estimates for blue dye and mixed tests increased the potential for these tests to 'miss' women with groin metastases.

AUTHORS' CONCLUSIONS

There is little difference in diagnostic test accuracy between the technetium and combined tests. The combined test may reduce the number of women with 'missed' groin node metastases compared with technetium only. Blue dye alone may be associated with more 'missed' cases compared with tests using technetium. Sentinel node assessment with technetium-based tests will reduce the need for IFL by 70% in women with early vulval cancer. It is not yet clear how the survival of women with negative sentinel nodes compares to those undergoing standard surgery (IFL). A randomised controlled trial of sentinel node dissection and IFL has methodological and ethical issues, therefore more observational data on the survival of women with early vulval cancer are needed.

Sentinel lymph node biopsy in vulval cancer: systematic review and meta-analysis

BACKGROUND

The purpose of this study was to determine the accuracy of sentinel lymph node (SLN) biopsy with technetium 99 (99mTc) and/or blue dye-enhanced lymphoscintigraphy in vulval cancer.

METHODS

Sensitive searches of databases were performed upto October 2013. Studies with at least 75% of women with FIGO stage IB or II vulval cancer evaluating SLN biopsy with 99mTc, blue dye or both with reference standard of inguinofemoral lymphadenectomy (IFL) or clinical follow-up were included. Meta-analyses were performed using Meta-Disc version 1.4.

RESULTS

Of the 2950 references, 29 studies (1779 women) were included; most of them evaluated 99mTc combined with blue dye. Of these, 24 studies reported results for SLN followed by IFL, and 5 reported clinical follow-up only for SLN negatives. Pooling of all studies was inappropriate because of heterogeneity. Mean SLN detection rates were 94.0% for 99mTc, 68.7% for blue dye and 97.7% for both. SLN biopsy had pooled sensitivity of 95% (95% CI 92-98%) with negative predictive value (NPV) of 97.9% in studies using 99mTc/blue dye, ultrastaging and immunohistochemistry with IFL as reference. Pooled sensitivity for SLN with clinical follow-up for SLN-negatives was 91% (85-95%) with NPV 95.6%. Patients undergoing SLN biopsy experienced less morbidity than those undergoing IFL.

CONCLUSIONS

Sentinel lymph node biopsy using 99mTC, blue dye and ultrastaging with immunohistochemistry is highly accurate when restricted to carefully selected patients, within a rigorous protocol, with close follow-up and where sufficient numbers for learning curve optimisation exist. Patients must make an informed choice between the slightly higher groin recurrence rates of SLN biopsy vs the greater morbidity of IFL.

The EANM clinical and technical guidelines for lymphoscintigraphy and sentinel node localization in gynaecological cancers

The accurate harvesting of a sentinel node in gynaecological cancer (i.e. vaginal, vulvar, cervical, endometrial or ovarian cancer) includes a sequence of procedures with components from different medical specialities (nuclear medicine, radiology, surgical oncology and pathology). These guidelines are divided into sectione entitled: Purpose, Background information and definitions, Clinical indications and contraindications for SLN detection, Procedures (in the nuclear medicine department, in the surgical suite, and for radiation dosimetry), and Issues requiring further clarification. The guidelines were prepared for nuclear medicine physicians. The intention is to offer assistance in optimizing the diagnostic information that can currently be obtained from sentinel lymph node procedures. If specific recommendations given cannot be based on evidence from original scientific studies, referral is made to "general consensus" and similar expressions. The recommendations are designed to assist in the practice of referral to, and the performance, interpretation and reporting of all steps of the sentinel node procedure in the hope of setting state-of-the-art standards for high-quality evaluation of possible metastatic spread to the lymphatic system in gynaecological cancer. The final result has been discussed by a group of distinguished experts from the EANM Oncology Committee and the European Society of Gynaecological Oncology (ESGO). The document has been endorsed by the SNMMI Board.

Sentinel lymph node detection and accuracy in vulvar cancer: Experience of a tertiary center in Turkey

OBJECTIVE

To explore the accuracy of sentinel lymph node (SLN) dissection in predicting regional lymph node status by using either only Technetium-99m-labelled (Tc-99m) or in combination with a blue dye in patients with squamous cell cancer of vulva.

MATERIAL AND METHODS

Twenty-one patients who had T1 (≤2 cm) or T2 (>2cm) tumors that did not encroach into the urethra, vagina or anus were included in the study. For the first twelve patients, Tc-99m was used for SLN identification, and the combined technique was used in subsequent patients. Preoperatively, Tc-99m and a blue dye was injected intradermally around the tumor. Following SLN dissection, complete inguinofemoral lymphadenectomy was performed.

RESULTS

We could detect SLN in all 21 patients (100%) by either Tc-99m or the combined method. SLN was found to be histopathologically negative in 13 groins via Tc-99m and 10 groins via the combined method. Twenty-one of these 23 (91.3%) groin non-SLN were also negative, but in two groins, we detected metastatic non-SLN.

CONCLUSION

Although SLN dissection appears promising in vulvar cancer, false negative cases are reported in the literature. Sentinel lymph node dissection without complete lymphadenectomy does not seem appropriate for routine clinical use, since it is known that groin metastasis is fatal.

A prospective study of sentinel lymph node detection in vulval carcinoma: is it time for a change in clinical practice?

OBJECTIVES

To determine the accuracy of sentinel lymph node (SLN) detection in vulval carcinoma and to report the reliability and safety of this procedure.

METHODS/MATERIALS

For a period of 6 years, we recruited women undergoing surgery for vulval carcinoma. All women had a preoperative biopsy confirming the depth of invasion greater than 1 mm. Sentinel lymph node detection was performed using the combined method (Tc-99m and methylene-blue dye). The standard management included complete inguinofemoral lymphadenectomy. When inguinofemoral lymph nodes were found grossly to be enlarged, these nodes were debulked, and the women subsequently treated with radiotherapy with or without chemotherapy. During the last 2 years of the study, a selected group of women had an SLN dissection alone. The SLNs were ultrastaged when they were negative on routine hematoxylin and eosin examination.

RESULTS

Among 60 women undergoing SLN detection, SLN was detected in 59 women (98.3%) with combined method. Blue dye did not detect an SLN in 3 women resulting in a 93.3% detection rate. The median SLN count was 2 nodes (range, 1-9). Of the 60 women, 41 had inguinofemoral lymphadenectomy, 4 had only enlarged inguinofemoral nodes debulked, and 15 had the SLN only removed. The non-SLN count was 9 nodes (range, 3-17). There were no false-negative SLNs. Twenty-one women (35%) had positive nodes on final histology. Ultrastaging increased detection of metastases in 6.9% of nodes relative to routine hematoxylin and eosin examination and upstaged 12% of women. The median follow-up was 24 months (range, 2-66 months).

CONCLUSIONS

Sentinel lymph node detection is safe and accurate in assessing lymph node status in women with vulval cancer undergoing staging. The combined method using Tc-99m and methylene blue dye injection for SLN detection has the best detection rate. Routine ultrastaging of negative SLN improves the detection of nodal metastases.

Sentinel lymph node detection in patients with vulvar carcinoma; Feasibility of intra-operative mapping with technetium-99m-labeled nanocolloid

AIMS

Sentinel lymph node (SLN) mapping appears to be feasible in patients with primary vulvar cancer. Previous protocols describe the injection of the technetium-99m-nanocolloid at least 3 h before surgery which involves two invasive procedures for the patient. In this study, we assessed the feasibility, safety, and accuracy of an intra-operative rather than preoperative SLN mapping in patients with primary vulvar cancer.

METHODS

Patients with histologically confirmed squamous cell vulvar cancer and clinically FIGO stage Ib disease underwent intra-operative SLN mapping by intradermal injection of the nanocolloid around the tumor. SLN were identified and removed before a complete inguinofemoral lymphnode dissection was performed. Surgical and pathologic data on all patients were prospectively entered into a database.

RESULTS

An SLN procedure was performed in 16 patients; 3 patients received unilateral lymphadenectomy, and 13 women underwent surgery on both groins. In all groins but 4 at least one SLN was clearly identified (detection rate 25/29, 86%). A median number of 2 SLN and 4 non-SLN per groin were removed. 3 of 16 patients (19%) had metastatic disease in the lymph nodes. There was no false negative SLN result.

CONCLUSION

Intra-operative SLN detection seems feasible in patients with early stage vulvar cancer. More patients need to be enrolled in this ongoing study before this more convenient technique can be considered safe.

Added value of intraoperative real-time imaging in searches for difficult-to-locate sentinel nodes

Localization of sentinel lymph nodes can be challenging if they are in difficult anatomic locations or near high radiotracer activity. The purpose of this study was to assess the value of intraoperative real-time imaging using a portable gamma-camera in conjunction with a conventional gamma-counting probe when it is difficult to localize the sentinel node.

METHODS

After (99m)Tc-nanocolloid injection, patients with various malignancies underwent presurgical lymphoscintigraphy followed by surgery (usually the next day). We evaluated 20 patients who required sentinel lymph node biopsy and in whom the location or other characteristics of the sentinel node would make intraoperative retrieval difficult. During surgery, the sentinel node was localized using a portable gamma-camera together with a hand-held gamma-probe. A (153)Gd pointer or (125)I seed was used to better depict the sentinel node location in real time.

RESULTS

Using only a conventional hand-held gamma-probe, surgeons were able to definitively localize the sentinel node in 15 of 20 patients. Intraoperatively, the portable gamma-camera showed uptake by the definite sentinel node in 19 of 20 patients and helped to precisely localize the node with the hand-held gamma-probe in 4 patients. In 1 of these patients, the sentinel node was metastatic.

CONCLUSION

The combination of a standard hand-held gamma-probe and real-time imaging provided by a portable gamma-camera offers a high intraoperative detection rate in patients with difficult sentinel node localization as assessed by presurgical lymphoscintigraphy.

Evaluation of preoperative lymphoscintigraphy and sentinel node procedure in vulvar cancer

OBJECTIVE

To assess the value of preoperative lymphoscintigraphy, and to evaluate the validity and feasibility of the sentinel node (SN) procedure in vulvar carcinoma.

STUDY DESIGN

Retrospective clinical and histopathological review of 77 patients with invasive squamous cell carcinoma in vulva who were treated at Karolinska University Hospital Stockholm, Sweden, from 2000 to 2007. The patients underwent SN mapping preoperatively with radioactive tracer and blue dye (n=60) or only blue dye (n=17). The SN was removed separately followed by complete inguinofemoral lymphadenectomy.

RESULTS

The relation between SNs detected on the scintigram and those found during surgery showed good agreement using weighted kappa. The detection rate of SN was 98% for radioisotope plus blue dye, and 94% for blue dye alone. Two cases of false negative SN (false negative rate 2.7%) were found, both with large midline tumors.

CONCLUSION

Preoperative scintigram is a valuable help to identify and localize the SNs and gives the best estimate of the accurate number but cannot determine if unilateral or bilateral groins should be explored in cases of midline tumors. Our results are in favor of using radioisotope and blue dye to identify the SNs. This study support previous reports that the method is not recommended for tumors larger than 40 mm to optimize detection of SN and minimize the false negative detection rate.

Size of sentinel-node metastasis and chances of non-sentinel-node involvement and survival in early stage vulvar cancer: results from GROINSS-V, a multicentre observational study

BACKGROUND

Currently, all patients with vulvar cancer with a positive sentinel node undergo inguinofemoral lymphadenectomy, irrespective of the size of sentinel-node metastases. Our study aimed to assess the association between size of sentinel-node metastasis and risk of metastases in non-sentinel nodes, and risk of disease-specific survival in early stage vulvar cancer.

METHODS

In the GROningen INternational Study on Sentinel nodes in Vulvar cancer (GROINSS-V), sentinel-node detection was done in patients with T1-T2 (<4 cm) squamous-cell vulvar cancer, followed by inguinofemoral lymphadenectomy if metastatic disease was identified in the sentinel node, either by routine examination or pathological ultrastaging. For the present study, sentinel nodes were independently reviewed by two pathologists.

FINDINGS

Metastatic disease was identified in one or more sentinel nodes in 135 (33%) of 403 patients, and 115 (85%) of these patients had inguinofemoral lymphadenectomy. The risk of non-sentinel-node metastases was higher when the sentinel node was found to be positive with routine pathology than with ultrastaging (23 of 85 groins vs three of 56 groins, p=0.001). For this study, 723 sentinel nodes in 260 patients (2.8 sentinel nodes per patient) were reviewed. The proportion of patients with non-sentinel-node metastases increased with size of sentinel-node metastasis: one of 24 patients with individual tumour cells had a non-sentinel-node metastasis; two of 19 with metastases 2 mm or smaller; two of 15 with metastases larger than 2 mm to 5 mm; and ten of 21 with metastases larger than 5 mm. Disease-specific survival for patients with sentinel-node metastases larger than 2 mm was lower than for those with sentinel-node metastases 2 mm or smaller (69.5%vs 94.4%, p=0.001).

INTERPRETATION

Our data show that the risk of non-sentinel-node metastases increases with size of sentinel-node metastasis. No size cutoff seems to exist below which chances of non-sentinel-node metastases are close to zero. Therefore, all patients with sentinel-node metastases should have additional groin treatment. The prognosis for patients with sentinel-node metastasis larger than 2 mm is poor, and novel treatment regimens should be explored for these patients.

Characteristics of sentinel lymph nodes' metastatic involvement in early stage of vulvar cancer

BACKGROUND

Nodal involvement is one of the most significant prognostic factors in early-stage vulvar cancer.

AIMS

To determine the diagnostic accuracy of sentinel lymph node (SLN) detection in early-stage vulvar cancer and to describe the characteristics of metastatic lymph node involvement.

METHODS

Of 23 women with early-stage squamous cell vulvar cancer included in the study, five had lateral lesions and 18 had midline lesions. SLN detection was performed by using a radioactive tracer and blue dye, followed by radical vulvectomy or radical wide excision with uni/bilateral inguinofemoral lymphadenectomy, depending on tumour size and localization. SLNs were subsequently examined with haematoxylin-eosin and immunohistochemistry.

RESULTS

The SLN detection was successful in all 23 women (100%) and in 38 of 41 groins (92.3%) tested. The total number of SLNs was 67, with an average of 1.76 per groin. In total, 20 positive SLNs were detected in 14 of 23 patients. From a total of 20 positive SLNs, micrometastases were found in five SLNs and isolated tumour cells in one SLN. We experienced one case with a false negativity of SLN. Sensitivity, negative predictive value, accuracy and false negativity of SLN detection were 93.3%, 88.8%, 95.6% and 7.1% respectively.

CONCLUSION

The SLN biopsy performed by an experienced team is a feasible method, with high accuracy in patients with early-stage vulvar cancer. Prognostic value of micrometastases should be confirmed in further studies.

The role of sentinel node biopsy in gynecological cancer: a review

PURPOSE OF REVIEW

In early-stage vulvar, cervical and endometrial cancer, lymph node status is the most important prognostic factor. Surgical treatment is aimed at removing the primary tumor and adequately staging the regional lymph nodes. As morbidity of regional lymphadenectomy is high, sentinel node biopsy is a technique with potential for adequate staging with less treatment-related morbidity. This manuscript reviews its current role in vulvar, cervical and endometrial cancer.

RECENT FINDINGS

In early-stage vulvar cancer, level 3 evidence indicates that it appears to be safe to omit inguinofemoral lymphadenectomy in case of a negative sentinel node. However, false-negative results with fatal consequences do occur and are often attributable to procedural failures. For early-stage cervical cancer, level 3 evidence points to an acceptable false-negative rate of a negative sentinel node; clinical utility and safety remain to be established. The optimal technique of the sentinel node biopsy in endometrial cancer is currently unclear.

SUMMARY

In early-stage vulvar cancer, data suggest that sentinel node biopsy could be offered as a treatment option instead of routine inguinofemoral lymphadenectomy. However, more (long-term follow-up) data are needed to further appreciate real clinical benefits. It is emphasized that the procedure should be performed by a skilled multidisciplinary team, centralized in oncology centers and preferably within the protection of clinical trials. For cervical cancer, data are promising, but routine application cannot be recommended due to lack of data on clinical utility and safety. For endometrial cancer, studies on the sentinel node biopsy are still in feasibility stage.

State of the Art of Sentinel Lymph Node Biopsy in Vulvar Carcinoma

Treatment for early-stage vulvar carcinoma has evolved from radical en bloc dissection to wide local incision with lymphadenectomy through separate groin incisions, to sentinel lymph node biopsy (SLNB). The morbidity of SLNB is far less than traditional inguinofemoral lymphadenectomy, with less lymphedema and sensory deficit, shorter hospital stays and fewer infections. A multidisciplinary approach is required, with success of the SLNB technique maximized when radiolabeled colloid is used, with blue dye added when further identification is needed. Frozen-section analysis, followed by ultrastaging of the nodal sample, minimizes the need for reoperations and decreases the risk of false negatives. We believe that SLNB will become the standard of care for treatment of early-stage vulvar carcinoma.

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.

Sentinel node dissection is safe in the treatment of early-stage vulvar cancer

PURPOSE

To investigate the safety and clinical utility of the sentinel node procedure in early-stage vulvar cancer patients.

PATIENTS AND METHODS

A multicenter observational study on sentinel node detection using radioactive tracer and blue dye was performed in patients with T1/2 (< 4 cm) squamous cell cancer of the vulva. When the sentinel node was found to be negative at pathologic ultrastaging, inguinofemoral lymphadenectomy was omitted, and the patient was observed with follow-up for 2 years at intervals of every 2 months. Stopping rules were defined for the occurrence of groin recurrences.

RESULTS

From March 2000 until June 2006, a sentinel node procedure was performed in 623 groins of 403 assessable patients. In 259 patients with unifocal vulvar disease and a negative sentinel node (median follow-up time, 35 months), six groin recurrences were diagnosed (2.3%; 95% CI, 0.6% to 5%), and 3-year survival rate was 97% (95% CI, 91% to 99%). Short-term morbidity was decreased in patients after sentinel node dissection only when compared with patients with a positive sentinel node who underwent inguinofemoral lymphadenectomy (wound breakdown in groin: 11.7% v 34.0%, respectively; P < .0001; and cellulitis: 4.5% v 21.3%, respectively; P < .0001). Long-term morbidity also was less frequently observed after removal of only the sentinel node compared with sentinel node removal and inguinofemoral lymphadenectomy (recurrent erysipelas: 0.4% v 16.2%, respectively; P < .0001; and lymphedema of the legs: 1.9% v 25.2%, respectively; P < .0001).

CONCLUSION

In early-stage vulvar cancer patients with a negative sentinel node, the groin recurrence rate is low, survival is excellent, and treatment-related morbidity is minimal. We suggest that sentinel node dissection, performed by a quality-controlled multidisciplinary team, should be part of the standard treatment in selected patients with early-stage vulvar cancer.

[Lymphadenectomy of the inguinal region and pelvis]

The draining lymph nodes of extra-abdominal tumors and malignant lesions of the lower extremity are located in the groin and iliac region. Malignancies with lymphatic drainage into this region include tumors of the anorectum, penis and vulva, skin (melanoma, squamous cell carcinoma), and soft tissue sarcomas. Current clinical research in biology, routes of lymphatic spread, and the possibility of marking the sentinel lymph node has directed lymphadenectomy strategy toward differential procedures, depending on the type of underlying malignancy. The spectrum of lymphadenectomy includes diagnostic lymph node removal of clinically enlarged nodes, removal of the sentinel node, and radical lymphadenectomy. Lymphadenectomy can also be indicated as a palliative procedure. The indications also depend on the type of tumor, previous treatment, and disease prognosis. This review presents the current state of indications and surgical techniques of inguinal and iliacal lymphadenectomy.