Preoperative sentinel lymph node localization in vulvar cancer: preliminary experience with inguinal intradermal contrast-enhanced ultrasound

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.

Contrast-enhanced ultrasound: a new tool for imaging the superficial lymphatic vessels of the upper limb

Background

Despite the new lymphatic imaging methods, there is still a need for a straightforward method of detecting lymphatic abnormalities. Our goal was to investigate the feasibility of applying a contrast enhanced ultrasound (CEUS) procedure as a new approach for visualising the superficial lymphatic vessels of the upper limb.

Methods

Thirty healthy volunteers were examined with CEUS after bilateral intradermal injection of Sonazoid® contrast agent in distal antebrachium. We registered factors affecting intradermal injections, imaging of the superficial lymphatic vessels and the enhancement time of contrast agent reaching the levels of elbow and axilla.

Results

CEUS imaging of superficial lymphatic vessels was successful in 59 of 60 upper limbs (98.3%). Median [interquartile ranges] enhancement times of contrast agent to reach the elbow (right 18 s [11–25], left 15 s [12–25]) and axilla (right 77 s [33–118], left 66 s [42–115]) were equally fast. Successful intradermal injections were found to result in two types of contrast enhancement (strong or moderate), while the enhancement time depended on the type of the successful injection. No major differences in enhancement times were observed related to sex, body mass index, age, or side of the arm.

Conclusions

The superficial lymphatic pathways of the upper limb can be visualised with CEUS imaging. Since enhancement time is dependent on the success of intradermal injections, one must pay attention to the injection technique. Further studies are needed to evaluate the method in patients with lymphatic function disorders such as breast cancer therapy related lymphoedema.

New developments in rare vulvar and vaginal cancers

PURPOSE OF REVIEW

To provide the latest insight on the rare vulvar and vaginal malignancies, able to impact on clinical practice, and to outline new potential research developments.

RECENT FINDINGS

Many efforts are being made to produce technical and scientific advances in the fields of vulvar and vaginal carcinoma, including imaging work-up, interventional procedures and minimally invasive surgical approach, as well as molecular profiling and identification of new target treatments.

SUMMARY

In the evaluation of lymph node status, ultrasound has demonstrated promising results because of high predictive value, low risk and low cost. Positron Emission Tomography-Computed Tomography is confirmed to be reliable and should be prospectively investigated for its potential applications in radiomics, whilst Fusion-US could allow a precision guidance in diagnostics and interventional procedures. Regarding interventional procedure, surgery is becoming less invasive with the aim to increase quality of life; in carefully selected patients it would be possible to overcome the current strict criteria in the use of sentinel node biopsy. Future research should focus on potential target therapy, on the basis of tumor-specific biological features.Rare cancers should be referred to experienced centers with a high case flow, able to offer a full range of diagnostic and therapeutical options and a multidisciplinary approach. Networking should be encouraged to promote research opportunities and enable data sharing and multicenter trials.

Therapeutic oxygen delivery by perfluorocarbon-based colloids

After the protocol-related indecisive clinical trial of Oxygent, a perfluorooctylbromide/phospholipid nanoemulsion, in cardiac surgery, that often unduly assigned the observed untoward effects to the product, the development of perfluorocarbon (PFC)-based O₂ nanoemulsions ("blood substitutes") has come to a low. Yet, significant further demonstrations of PFC O₂-delivery efficacy have continuously been reported, such as relief of hypoxia after myocardial infarction or stroke; protection of vital organs during surgery; potentiation of O₂-dependent cancer therapies, including radio-, photodynamic-, chemo- and immunotherapies; regeneration of damaged nerve, bone or cartilage; preservation of organ grafts destined for transplantation; and control of gas supply in tissue engineering and biotechnological productions. PFC colloids capable of augmenting O₂ delivery include primarily injectable PFC nanoemulsions, microbubbles and phase-shift nanoemulsions. Careful selection of PFC and other colloid components is critical. The basics of O₂ delivery by PFC nanoemulsions will be briefly reminded. Improved knowledge of O₂ delivery mechanisms has been acquired. Advanced, size-adjustable O₂-delivering nanoemulsions have been designed that have extended room-temperature shelf-stability. Alternate O₂ delivery options are being investigated that rely on injectable PFC-stabilized microbubbles or phase-shift PFC nanoemulsions. The latter combine prolonged circulation in the vasculature, capacity for penetrating tumor tissues, and acute responsiveness to ultrasound and other external stimuli. Progress in microbubble and phase-shift emulsion engineering, control of phase-shift activation (vaporization), understanding and control of bubble/ultrasound/tissue interactions is discussed. Control of the phase-shift event and of microbubble size require utmost attention. Further PFC-based colloidal systems, including polymeric micelles, PFC-loaded organic or inorganic nanoparticles and scaffolds, have been devised that also carry substantial amounts of O₂. Local, on-demand O₂ delivery can be triggered by external stimuli, including focused ultrasound irradiation or tumor microenvironment. PFC colloid functionalization and targeting can help adjust their properties for specific indications, augment their efficacy, improve safety profiles, and expand the range of their indications. Many new medical and biotechnological applications involving fluorinated colloids are being assessed, including in the clinic. Further uses of PFC-based colloidal nanotherapeutics will be briefly mentioned that concern contrast diagnostic imaging, including molecular imaging and immune cell tracking; controlled delivery of therapeutic energy, as for noninvasive surgical ablation and sonothrombolysis; and delivery of drugs and genes, including across the blood-brain barrier. Even when the fluorinated colloids investigated are designed for other purposes than O₂ supply, they will inevitably also carry and deliver a certain amount of O₂, and may thus be considered for O₂ delivery or co-delivery applications. Conversely, O₂-carrying PFC nanoemulsions possess by nature a unique aptitude for ¹⁹F MR imaging, and hence, cell tracking, while PFC-stabilized microbubbles are ideal resonators for ultrasound contrast imaging and can undergo precise manipulation and on-demand destruction by ultrasound waves, thereby opening multiple theranostic opportunities.

Value of preoperative staging of endometrial carcinoma with contrast-enhanced ultrasonography: A PRISMA compliant meta-analysis

INTRODUCTION

Endometrial carcinoma (EC) is the most common gynecologic carcinoma in developed countries and accounts for nearly 5% of carcinoma cases and more than 2% of deaths due to female carcinomas worldwide. Because of this reported risk, it is very important to diagnose and stage it accurately. Therefore, we investigated the staging accuracy of EC with contrast-enhanced ultrasonography (CEUS). Due to a lack of studies on the use of CEUS in staging EC, we performed a systematic review and meta-analysis.

METHOD

We searched PubMed, EMBASE, Cochrane Library, Scopus, Web of science, China National Knowledge Infrastructure (CNKI), and CBM for studies on CEUS in EC diagnosis. Our search keywords were "ultrasonic angiography," "endometrial neoplasms," and their synonyms. The studies were screened according to the inclusion and exclusion criteria, and 4 tabular data were extracted. Quality evaluation was performed with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) scale. Statistical analysis was done with Stata version 15.1. A random effect model was selected to calculate the pooled sensitivity and specificity. The summary receiver operating characteristic (SROC) curve was obtained, and the area under the curve was calculated.

RESULT

Fifteen studies with 685 patients were included in this quantitative synthesis. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio (OR) of CEUS in the diagnosis of EC was 0.81 (95% confidence interval, .76-.85), .90 (.87-.92), 8 (5.8-11.1), .21 (.16-.28), and 38 (22-67), respectively. The area under the curve was 0.93 (.90-.95).

CONCLUSION

CEUS has a high sensitivity and specificity in the diagnosis of EC. It can be considered as an effective and feasible method for EC staging.

Detection of lymph node metastases in penile cancer

Penile cancer (PC) is a relatively rare malignancy in the United States (US) but a greater concern in developing nations. Lymph node imaging remains critical to the staging and treatment of this disease as metastases develop in a predictable, anatomic fashion. Early surgical intervention remains a mainstay in treatment and imaging often aids in decision making. This review highlights the indications for imaging in both low-stage and advanced disease. Furthermore, we discuss the benefits and limitations of currently available imaging for staging of inguinal and pelvic lymph nodes in PC and novel modalities in development.