Sentinel node localization by lymphoscintigraphy: a reliable technique with widespread applications

The role of the sentinel lymph node in vulvar cancer

The aim of this study was to update clinical practice applications and technical procedures regarding sentinel lymph node (SLN) biopsy in vulvar cancer considering European experts' opinions from this field. Systematic data search performed using PubMed/medline database up to May 20, 2020. Focus was only for English language publications of original studies on SLN biopsy in vulvar cancer. Given the basis of published evidence and the consensus of European experts, this study provides an updated overview on clinical applications and technical procedures of SLN biopsy in vulvar cancer. 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 advise 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.

A critical review of variables affecting the accuracy and false-negative rate of sentinel node biopsy procedures in early breast cancer

Radionuclide sentinel lymph node localization and biopsy is a staging procedure that is being increasingly used to evaluate patients with invasive breast cancer who have clinically normal axillary nodes. The most important prognostic indicator in patients with invasive breast cancer is the axillary node status, which must also be known for correct staging, and influences the selection of adjuvant therapies. The accuracy of sentinel lymph node localization depends on a number of factors, including the injection method, the operating surgeon's experience and the hospital setting. The efficacy of sentinel lymph node mapping can be determined by two measures: the sentinel lymph node identification rate and the false-negative rate. Of these, the false-negative rate is the most important, based on a review of 92 studies. As sentinel lymph node procedures vary widely, nuclear medicine physicians and radiologists must be acquainted with the advantages and disadvantages of the various techniques. In this review, the factors that influence the success of different techniques are examined, and studies which have investigated false-negative rates and/or sentinel lymph node identification rates are summarized.

Superparamagnetic iron oxide nanoparticles: nodal metastases and beyond

Superparamagnetic iron oxide (SPIO) nanoparticles are unique MR contrast agents and are of great interest for their multiple potentials. SPIO nanoparticles have a higher diagnostic accuracy for detecting metastatic lymph nodes than conventional MR studies, particularly in head and neck. The impact of this unique MR contrast agent on treatment decision of patients with head and neck cancer needs to be investigated in comparison with contrast-enhanced CT. As MR technology advances, the accuracy of SPIO nanoparticles for detection of metastasis certainly improves; thus, 1 day we may be able to reliably detect metastases in stage N0 patients, so that treatment strategy is established for each individual patient. This article presents physiologic properties of SPIO, technical considerations and diagnostic accuracy for imaging with SPIO, and other potential applications of SPIO agents.

Vulvar melanoma: a report of 20 cases and review of the literature

BACKGROUND

Vulvar melanoma is the second most common vulvar malignancy and represents a significant women's health issue.

OBJECTIVE

To report experience with 21 cases of vulvar melanoma in 20 patients and to review the literature about the condition.

METHODS

Parameters retrospectively reviewed included age at diagnosis, family history of melanoma, location on the vulva, atypical nevi, Breslow depth, ulceration status, histologic pattern, presenting signs and symptoms, and the results of sentinel lymph node biopsy. Molecular characterization of the melanocortin type 1 receptor was performed in 1 patient.

RESULTS

A family history of cutaneous melanoma was present in 15% of cases. The mean Breslow depth was 2.8 mm (range, 0.0-11.0 mm). Ten patients successfully underwent sentinel lymph node biopsy, results of which were positive in 2 (20%). Reported for the first time is that one patient had a germline mutation in the melanocortin type 1 receptor.

CONCLUSION

Vulvar and cutaneous melanoma behave similarly despite their unique pathogeneses. Sentinel lymph node biopsy can be performed successfully for vulvar melanoma.

Vulvar Melanoma: Review of Diagnosis, Staging, and Therapy

OBJECTIVES

To update, assimilate, and bridge the contemporary literature on vulvar and cutaneous melanoma regarding diagnosis, staging, and therapy to provide a useful clinical reference for managing and counseling for affected patients.

MATERIALS AND METHODS

A computerized search for reports in the literature up to June 2003 was carried out using PubMed and MEDLINE databases. Multidisciplinary involvement was used in evaluating the available data and formulating conclusions.

RESULTS

More than 300 reports were reviewed. Diagnosis, staging, and therapy aspects of vulvar melanoma are summarized.

CONCLUSIONS

Vulvar melanoma represents a subtype of cutaneous melanoma, with similar prognostic and staging factors. The most recent American Joint Committee on Cancer staging system for cutaneous melanoma is applicable to vulvar melanoma. Sentinel lymph node biopsy is reliable for staging the regional lymph node basin for vulvar melanoma. Standardized documentation of clinical and histopathologic parameters is needed to standardize grouping of cases for future comparison studies.

Optical and acoustical interrogation of submicron contrast agents

Unlike conventional ultrasound contrast agents with a diameter of several microns, in this paper we explore the use of submicron contrast agents for the detection and localization of lymph nodes. The submicron agents are gas-filled, double-walled microspheres that rupture when exposed to ultrasound energy at megahertz frequencies. In this study, three experimental systems are combined with model predictions to assist in understanding the response of these unique agents to a range of signal transmission parameters. Optical experimental results for each agent delineate the relative expansion as a function of acoustical peak negative pressure, pulse length, and center frequency. The optical images demonstrate an order of magnitude expansion in radius during the pulse rarefaction, in which the expansion magnitude is dependent on the transmitted pressure and frequency. Simulations using a modified Rayleigh-Plesset model predict an increasing relative expansion for the microbubbles (initial bubble radius ranging from 0.3-1.3 microm) with increasing pressure and decreasing initial radius. Acoustically recorded frequency spectra reveal the presence of harmonics for a range of transmitted pulses. In addition, in-vivo results from a normal canine model demonstrate marked contrast enhancement of first order lymph nodes. We hope to offer an alternative to present intra-operative procedures for sentinel node detection.

Lymphatic mapping and sentinel node identification in squamous cell carcinoma and melanoma of the head and neck

AIM

The aim of our study was to evaluate the role of scintigraphy in lymphatic mapping and in the identification of the sentinel lymph node (SLN) in patients with head and neck cancer.

METHODS

Between September 1999 and February 2001 we enrolled 22 consecutive patients with cancer in the head and neck region: five squamous cell carcinomas, one Merkel cell tumor of the cheek, and 16 malignant melanomas. Lymphoscintigraphy was performed three hours before surgery after injection of 30-50 MBq of 99mTc -Nanocoll in 0.3 mL; the dose was fractionated by injecting the radiotracer at two points around the lesion. Static acquisition (anterior and/or lateral views, 512 x 512 matrix, 5 mins pre-set time) was started immediately after the injections so as to visualize the pathways of lymphatic drainage. The skin projection of the SLN was marked with ink. Intraoperative SLN detection was performed with perilesional injection of patent blue.

RESULTS

SLNs were found with lymphoscintigraphy in all patients. Thirty-three SLNs were identified: one occipital node, three nodes at the base of the tongue, 10 superficial lateral nodes (external jugular), five submandibular nodes, five submental nodes, three mastoid nodes and six supraclavicular nodes. Biopsy was performed in 21/22 patients. In 20/22 patients the first lymph nodes were visualized in the proximal cranial regions (retroauricular, jugular and submandibular) at five minutes post injection. The SLN positivity rate was 13.6% (three patients). All patients with tumor-positive SLNs were submitted to radical dissection. Poor concordance in the detection of sentinel nodes was observed with patent blue.

CONCLUSIONS

The flow of nanocolloid in the lymph vessels of the head is rapid. In our experience immediate scintigraphic imaging was essential to visualize the pathways of lymphatic drainage and the first SLN. Radioguided SLN biopsy is therefore recommended within three hours. Injection of patent blue is inadvisable because of the poor concordance with lymphoscintigraphy and the risk of permanent tattooing of the face.

Comparison between periareolar and peritumoral injection of radiotracer for sentinel lymph node biopsy in patients with breast cancer

BACKGROUND

The technique of sentinel lymph node (SLN) biopsy in patients with breast cancer varies among reports, and the optimal method remains to be established, particularly with regard to the site of radiotracer injection. The aim of this study was to compare periareolar and peritumoral injection of radiotracer in detecting SLN in patients with breast cancer.

METHODS

Patients with T1-2 breast cancer (n = 155) were enrolled in this study. In phase 1 (n = 62), SLN biopsy was performed by using peritumoral injection of blue dye alone followed by backup axillary lymph node dissection. In phase 2, SLN biopsy was performed by using peritumoral injection of blue dye and peritumoral (group A, n = 41) or periareolar (group B, n = 52) injection of technetium 99m tin colloid.

RESULTS

In phase 1, the detection rate of SLN was 81% and the false-negative rate was 5.6%, indicating our skill in SLN biopsy. In phase 2, the success rate of lymphoscintigraphy was significantly (P <.001) higher in group B (90%) than in group A (51%). The mean ex vivo radioactivity of SLN in group B (117 counts per second; range, 5 to 900) was also significantly (P <.05) higher than in group A (51 counts per second; range, 8 to 260). In addition, the detection rate of SLN was significantly (P <.05) higher in group B (100%) than in group A (90%).

CONCLUSIONS

Periareolar injection of radiotracer for SLN biopsy is superior to peritumoral injection because of its simplicity, achieving a high success rate in lymphoscintigraphy and SLN detection.

Vulvar melanoma: a retrospective analysis and literature review

OBJECTIVE

This review focuses on current directions in the staging and treatment of melanoma of the vulva.

METHODS

All women treated for invasive melanoma of the vulva at the University of Virginia Health Sciences Center from 1980 through 2000 were identified through a retrospective review of the records of the Division of Gynecologic Oncology. Their treatments and outcomes were then analyzed and presented.

RESULTS

Over the 20-year study period, 14 cases of melanoma of the vulva were identified. Of the 14 patients treated with curative intent, 6 developed recurrences following the completion of primary therapy, and all are dead from their disease. The mean duration from completion of therapy to recurrence was 7.5 months; the mean survival following recurrence was 17 months.

CONCLUSION

One-centimeter skin margins appear adequate for vulvar melanomas <1 mm thick, and 2-cm margins appear adequate for intermediate-thickness melanomas (1-4 mm). In all cases it is necessary to include at least a 1-cm-deep margin extending through the subcutaneous fat to the muscular fascia below. Elective node dissection seems to offer no additional advantage in superficial lesions <0.76 mm thick, and its role in deeper lesions is still uncertain.

Sentinel lymph node identification and sampling in women with early breast cancer using 99m Tc labelled dextran 500 and patent blue V dye

The status of the homolateral axillary lymph nodes is still the most important prognostic factor in early stage breast cancer. The information obtained from the pathological examination of the lymph nodes guides is of critical importance in the decision process regarding the use of postoperative adjuvant therapy. However, lymph node axillary dissection can be followed by significant locoregional morbidity. The sentinel lymph node (SLN) technique was developed as a means of avoiding the full exploration of the axilla and consists in the identification of the first lymph node in the lymphatic drainage system of the breast tumour in the homolateral axilla. It has been demonstrated that the status of the SLN is highly predictive for the presence or absence of tumour involvement in the remaining lymph nodes in the axilla. In this study we evaluated the SLN technique using both 99mTc labelled dextran 500 and patent blue V dye in relation to the classical lymph node resection a series of 56 women with early breast cancer who attended the Breast Unit of the Academic Hospital of the Federal University of Rio Grande do Sul, Brazil. To our knowledge this is the first report in the literature of the utilization of 99mTc dextran 500 for the SLN technique. As there are no similar commercially available dedicated radiopharmaceuticals labelled for use in lymphoscintigraphy studies, we report on an effective method to label dextran 500 with 99mTc which proved to be simple, inexpensive and yielded similar results for SLN identification compared with those given in the literature. The median age of the patients was 57 years (range 32-82 years). Seventeen patients were age 50 years or less, and 39 patients were older than 50 years. The median tumour size was 2.0 cm (range 0.8-7.0 cm). The mapping of the SLN was possible in all cases during the transoperative period by using a hand-guided gamma probe and a blue dye. A median of 2.0 (range 1-5) SLN were excised per patient. The median of axillary lymph nodes excised per patient was 21 (range 10-36). The calculated sensitivity and specificity of the method were 95.6% and 100%, respectively. The negative predictive value and overall accuracy were 97% and 98.2%, respectively. In conclusion, the SLN technique was feasible and produced similar positive results as previously reported in the literature.