Effects of previous surgery on the detection of sentinel nodes in women with vulvar cancer

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.

Detection of sentinel lymph node in vulvar cancer using 99mTc-labeled colloid lymphoscintigraphy, blue dye, and indocyanine-green fluorescence: a meta-analysis of studies published in 2010-2020

OBJECTIVES

Sentinel lymph node (SLN) biopsy is widely accepted in the surgical staging of early vulvar cancer, although the most accurate method for its identification is not yet defined. This meta-analysis aimed to determine the technique with the highest pooled detection rate (DR) for the identification of SLN and compare the average number of SLNs detected by planar lymphoscintigraphy (PL), single-photon emission computed tomography/computed tomography (SPECT/CT), blue dye and indocyanine green (ICG) fluorescence.

METHODS

The meta-analysis was conducted according to the PRISMA guideline. The search string was: "sentinel" and "vulv*", with date restriction from 1st January 2010 until Dec 31st, 2020. Three investigators selected studies based on: (1) a study cohort or a subset of a minimum of 10 patients with vulvar cancer undergoing either PL, SPECT/CT, blue-dye, or ICG fluorescence for the identification of SLN; (2) the possibility to extrapolate the DR or the average number of SLNs detected by a single technique (3) no evidence of other malignancies in the patient history.

RESULTS

A total of 30 studies were selected. In a per-patient and a per-groin analysis, the DR for SLN of PL was respectively 96.13% and 92.57%; for the blue dye was 90.44% and 66.21%; for the ICG, the DR was 91.90% and 94.80%. The pooled DR of SPECT/CT was not calculated, since only two studies were performed in this setting. At a patient-based analysis, no significant difference was documented among PL, blue dye, and ICG (p = 0.28). At a per-groin analysis, PL and ICG demonstrated a significantly higher DR compared to blue dye (p < 0.05). The average number of SLNs, on a per-patient analysis, was available only for PL and ICG with a median number of 2.61 and 1.78 lymph nodes detected, respectively, and no significant statistical difference.

CONCLUSIONS

This meta-analysis favors the use of ICG and PL alone and in combination over blue dye for the identification of the SLN in vulvar cancer. Future studies may investigate whether the combined approach allows the highest DR of SLN in patients with vulvar cancer.

The giant steps in surgical downsizing toward a personalized treatment of vulvar cancer

The present article aims to highlight the importance of changes of personalized surgical treatment for vulvar cancer. Current international literature regarding surgical treatment of vulvar cancer was evaluated. This included several studies and systematic reviews. Radical surgery approach, such as en bloc resection, was the first therapeutic option and the standard care for many years, even if burdened with a high complication rate and frequently disfiguring. Taussing and Way introduced radical vulvectomy approach with en bloc bilateral inguinal-femoral lymphadenectomy; modified radical vulvectomy was developed, with a wide radical excision of the primary tumor. The role of inguinofemoral lymphadenectomy (mono or bilateral) changed in the years too, particularly with the advent of SLN biopsy as minimally invasive surgical approach for lymph node staging, in patients with unifocal cancer <4 cm, without suspicious groin nodes. More personalized and conservative surgical approach, consisting of wide local or wide radical excisions, is necessary to reduce complications as lymphedema or sexual disfunction. The optimal surgical management of vulvar cancer needs to consider dimensions, staging, depth of invasion, presence of carcinoma at the surgical margins of resection and grading, with the goal of making the treatment as individualized as possible.

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.

The Basics of Sentinel Lymph Node Biopsy: Anatomical and Pathophysiological Considerations and Clinical Aspects

Sentinel lymph node (SLN) is the first node to receive the drainage directly from a tumor. Detection and pathological examination of the SLN is an important oncological procedure that minimizes morbidity related to extensive nodal dissection. SLN biopsy was first reported in 1960 but took approximately 40 years to come into general practice following reports of good outcomes in patients with melanoma. After many years of observation and research on its use in various malignancies SLN biopsy has become the standard surgical treatment in patients with malignant melanoma, breast, vulvar, and cervical cancers. Along with the introduction of new technologies, such as the fluorescent dyes indocyanine green (ICG) and near-infrared fluorescence (NIR), and pathologic ultrastaging, SLN detection rate has increased and false-negative rate has decreased. This literature review aimed to present an overview of the basic concepts and clinical aspects of SLN biopsy in the light of the current research.

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.

Lymphatic mapping and sentinel node biopsy in squamous cell carcinoma of the vulva: systematic review and meta-analysis of the literature

OBJECTIVES

We reviewed the available literature on the accuracy of sentinel node (SN) mapping in the inguinal lymph node staging of vulvar squamous cell carcinoma (SCC).

METHODS

Medline and SCOPUS were searched by using "sentinel AND vulv*" as key words. Studies evaluating the accuracy of SN mapping in the inguinal lymph node staging of vulvar SCC were included if enough data could be extracted for calculation of detection rate and/or sensitivity. Only studies validated by inguinal lymph node dissection were included for sensitivity meta-analysis.

RESULTS

Forty-nine studies were included in the systematic review. Pooled patient and groin basis SN detection rates were 94.4% [92.4-95.9] and 84.6% [80.5-88], respectively. Pooled patient and groin basis sensitivity were 92% [90-95] and 92% [89-94], respectively (or 8% [5-10] and 8% [6-11] false negative rates). Pooled negative predictive values were 97% [96-98] and 98% [97-99] for patient and groin basis analyses respectively. SN detection rate and sensitivity were related to mapping method (blue dye, radiotracer, or both) and location of the tumor (midline vs. lateral tumors). Patients with palpable inguinal nodes had lower detection rate and sensitivity.

CONCLUSION

SN mapping is an accurate method for inguinal node staging in vulvar SCC. Combining radiotracer and blue dye methods and excluding patients with palpable inguinal nodes result in the highest detection rate and sensitivity. For midline tumors possible false negative results of SN mapping should be taken into account.

Intraoperative imaging

Intraoperative image is a rapidly expanding field encompassing many applications that use a multitude of technologies. Some of the these applications have been in use for many years and are firmly embedded in, and indispensable to, clinical practice (e.g. the use of X-ray to locate foreign bodies during surgery or oocyte retrieval under ultrasound guidance. In others, the application may have been in use in one discipline but not yet fully explored in another. Examples include the use of intraoperative ultrasound with or without contrast enhancement for the detection of hepatic metastases not identified preoperatively, and the effect of such additional information on the ultimate operative procedure. Intraoperative identification of sentinel lymph nodes has been explored in many specialties to a varying extent, with the aim of fine tuning and avoiding unnecessary surgery. In both these instances, we do not know the long-term effect of these interventions on patient survival or quality of life. In this chapter, we will explore the available evidence on these applications and current advances in the new technology in general, with a specific focus on gynaecology.