Anaphylaxis after peritumoral injection of sulphan blue 1% for identification of the sentinel node in lymphatic mapping of the breast

Subdermal Ultrasound Contrast Agent Injection for Sentinel Lymph Node Identification: An Analysis of Safety and Contrast Agent Dose in Healthy Volunteers

OBJECTIVES

Mapping of the lymphatic chain for identification of the sentinel lymph node (SLN) is an important aspect of predicting outcomes for patients with breast cancer, and it is usually performed as an intraoperative procedure using blue dye and/or radiopharmaceutical agents. Recently, the use of contrast-enhanced ultrasound (CEUS) has been proposed as an alternative imaging technique for this mapping. The objective of this study was to evaluate the use of subdermal administration of the ultrasound (US) contrast agent Sonazoid (GE Healthcare, Oslo, Norway) in terms of patient safety and to select the dose to be used for lymphatic applications in humans.

METHODS

This study was performed in 12 female volunteers who received bilateral subdermal injections of Sonazoid (1 or 2 mL dose) in the mid-upper outer quadrant of their breasts at 2 different time points. Contrast-enhanced US examinations were performed 0, 0.25, 0.5, 1, 2, 4, 6, and 24 hours after injection to identify SLNs.

RESULTS

Sentinel lymph nodes were identified within the first hour after injection as enhanced structures, and there was no significant difference by dose in the number of SLNs identified (P = .74). The volunteers only had minor adverse experiences (AEs) that resolved completely without intervention by study completion.

CONCLUSIONS

The subdermal use of Sonazoid in this study showed only minor local and nonsignificant AEs that were completely resolved without any intervention. Two different doses were compared with no significant differences observed between them. Hence, the lower dose studied (1 mL) was selected for use in future clinical studies.

The inextricable axis of targeted diagnostic imaging and therapy: An immunological natural history approach

In considering the challenges of approaches to clinical imaging, we are faced with choices that sometimes are impacted by rather dogmatic notions about what is a better or worse technology to achieve the most useful diagnostic image for the patient. For example, is PET or SPECT most useful in imaging any particular disease dissemination? The dictatorial approach would be to choose PET, all other matters being equal. But is such a totalitarian attitude toward imaging selection still valid? In the face of new receptor targeted SPECT agents one must consider the remarkable specificity and sensitivity of these agents. (99m)Tc-Tilmanocept is one of the newest of these agents, now approved for guiding sentinel node biopsy (SLNB) in several solid tumors. Tilmanocept has a Kd of 3×10(-11)M, and it specificity for the CD206 receptor is unlike any other agent to date. This coupled with a number of facts, that specific disease-associated macrophages express this receptor (100 to 150 thousand receptors), that the receptor has multiple binding sites for tilmanocept (>2 sites per receptor) and that these receptors are recycled every 15 min to bind more tilmanocept (acting as intracellular "drug compilers" of tilmanocept into non-degraded vesicles), gives serious pause as to how we select our approaches to diagnostic imaging. Clinically, the size of SLNs varies greatly, some, anatomically, below the machine resolution of SPECT. Yet, with tilmanocept targeting, the SLNs are highly visible with macrophages stably accruing adequate (99m)Tc-tilmanocept counting statistics, as high target-to-background ratios can compensate for spatial resolution blurring. Importantly, it may be targeted imaging agents per se, again such as tilmanocept, which may significantly shrink any perceived chasm between the imaging technologies and anchor the diagnostic considerations in the targeting and specificity of the agent rather than any lingering dogma about the hardware as the basis for imaging approaches. Beyond the elements of imaging applications of these agents is their evolution to therapeutic agents as well, and even in the neo-logical realm of theranostics. Characteristics of agents such as tilmanocept that exploit the natural history of diseases with remarkably high specificity are the expectations for the future of patient- and disease-centered diagnosis and therapy.

Image of tumor metastasis and inflammatory lymph node enlargement by contrast-enhanced ultrasonography

AIM: To compare the difference between tumor-induced lymph node enlargement and inflammation-induced lymph node enlargement by contrast-enhanced ultrasonography and pathological findings.

METHODS: A model of tumor-induced lymph node metastasis was prepared by embedding a VX2 tumor into the hind paws of white rabbits. A model of inflammation-induced enlargement was prepared by injecting a suspension of Escherichia coli into separate hind paws of white rabbits. Then, a solution of Sonazoid™ (GE Healthcare, Oslo, Norway) was injected subcutaneously in the proximity of the lesion followed by contrast-enhanced ultrasonography of the enlarged popliteal lymph nodes.

RESULTS: In the contrast-enhanced ultrasonography of the tumor-induced metastasis model, the sentinel lymph node was imaged. An area of filling defect was observed in that enlarged lymph node. In the histology examination, the area of filling defect corresponded to the metastatic lesion of the tumor. Contrast-enhanced ultrasonography of the model on inflammation-induced lymph node enlargement, and that of the acute inflammation model performed 3-7 d later, revealed dense staining that was comparatively uniform. The pathological findings showed acute lymphadenitis mainly due to infiltration of inflammatory cells. Contrast-enhanced ultrasonography that was performed 28 d post-infection in the acute inflammation model showed speckled staining. Inflammation-induced cell infiltration and fiberization, which are findings of chronic lymphadenitis, were seen in the pathological findings.

CONCLUSION: Sentinel lymph node imaging was made possible by subcutaneous injection of Sonazoid™. Contrast-enhanced ultrasonography was suggested to be useful in differentiating tumor-induced enlargement and inflammation-induced enlargement of lymph nodes.

Contrast-enhanced ultrasound imaging of sentinel lymph nodes after peritumoral administration of Sonazoid in a melanoma tumor animal model

OBJECTIVES

The purpose of this study was to compare lymphosonography (ie, contrast-enhanced ultrasound imaging [US] after interstitial injection of a US contrast agent) for the detection of sentinel lymph nodes (SLNs) in swine with naturally occurring melanoma tumors to lymphoscintigraphy using blue dye-guided surgical dissection as the reference standard. Also, we sought to determine if lymphosonography can be used to characterize SLNs.

METHODS

Sixty-three swine with 104 melanomas were evaluated. Contrast-specific US was performed after peritumoral injection (1 mL dose) of Sonazoid (GE Healthcare, Oslo, Norway). Lymphoscintigraphy was performed after peritumoral injections of technetium Tc 99m sulfur colloid. Peritumoral injection of 1% Lymphazurin (Ben Venue Labs, Inc, Bedford, OH) was used to guide SLN resection. The accuracy of SLN detection with the two imaging modalities was compared using the McNemar test. The SLNs were qualitatively and quantitatively characterized as benign or malignant based on the lymphosonography results with histopathology and RNA analyses used as the reference standards.

RESULTS

Blue dye-guided surgery identified 351 SLNs. Lymphosonography detected 293 SLNs and 11 false-positives, while lymphoscintigraphy detected 231 SLNs and 20 false-positives. The accuracy of SLN detection was 81.8% for lymphosonography, which was significantly higher than the 63.2% achieved with lymphoscintigraphy (P < .0001). The accuracy of lymphosonography for SLN characterization was 80%. When the size of the enhanced SLN was taken into consideration to characterize SLNs, the accuracy was 86%.

CONCLUSIONS

Lymphosonography is statistically better than lymphoscintigraphy for the detection of SLNs in this animal model. The ability to use lymphosonography as a means to characterize SLNs as benign or malignant is limited.

Anaphylaxis to Patent Blue V. I. Clinical aspects

BACKGROUND

The dye Patent Blue V (PBV) is increasingly used for staging procedures in operable breast cancer, but is reported to cause adverse reactions. The aim of this study was to present the clinical features and the results of follow-up examinations in patients with such reactions.

METHODS

We studied nine patients with hypersensitivity reactions to PBV between 1999 and 2006 who were identified through the Norwegian network for reporting and investigating allergic reactions during anesthesia.

RESULTS

We observed incidences of 0.5% (7/1418) for all kinds of PBV reactions and 0.4% (5/1418) for anaphylaxis. Typical clinical features included: (i) cardiovascular and/or cutaneous symptoms, (ii) a delay in symptoms, compared to the time of dye injection, (iii) poor response to ephedrine and intravenous fluid, and (iv) need for adrenaline administration, sometimes prolonged, for circulatory stabilization. Cutaneous manifestations were noted in five of the seven patients with anaphylaxis and two additional patients without circulatory instability. During anaphylactic reactions, serum tryptase was increased in six patients and normal in one. Serum tryptase was normal in one patient with skin symptoms only. Skin prick tests to PBV were positive in all eight patients tested, including the two with skin manifestations only.

CONCLUSION

The clinical features and the results of follow-up studies strongly suggest that these reactions are IgE mediated.

Gray-scale contrast-enhanced ultrasonography of sentinel lymph nodes in a metastatic breast cancer model

RATIONALE AND OBJECTIVES

Previous studies showed it was possible to employ sonographic contrast agent for identification of the sentinel lymph nodes (SLNs). This study is to investigate the usefulness of SonoVue (a sonographic contrast agent) and gray-scale contrast-enhanced ultrasonography (CEUS) for detecting the SLNs in a metastatic breast cancer model.

MATERIALS AND METHODS

CEUS was performed in 12 female rabbits with breast VX2 tumor after subcutaneous administration of SonoVue. The site, number, and pattern of enhancement of the SLNs were observed and recorded. After CEUS, 0.5 mL of blue dye was injected into the same location as SonoVue and the SLNs were detected by surgical dissection. The findings of CEUS were compared with those of blue dye.

RESULTS

Of the 12 tumors assessed, a total of 17 enhanced SLNs were detected by CEUS. Among them, a single SLN was detected in eight tumors, two SLNs in three tumors, and three SLNs in one tumor. All the SLNs showed partial enhancement on CEUS. Nineteen SLNs were identified by blue dye with surgical dissection. There were no false-positive CEUS findings in terms of SLN detection. The overall sensitivity of CEUS for detecting SLNs was 89.5% (17/19). Among the 17 SLNs detected by CEUS, tumor metastases were identified histopathologically in 4 SLNs, whereas proliferation of lymphatic tissue was identified in the other 13 SLNs.

CONCLUSIONS

CEUS combined with SonoVue is useful for detecting SLNs, although it may not be helpful for detecting metastases in SLNs.

Contrast-enhanced sonographic imaging of lymphatic channels and sentinel lymph nodes

OBJECTIVE

The purpose of this study was to determine whether lymphatic channels (LCs) and sentinel lymph nodes (SLNs) could be detected on sonographic imaging after subcutaneous, submucosal, or parenchymal injections of a sonographic contrast agent (ie, lymphosonography) in a variety of anatomic locations in several animal models.

METHODS

Eight swine, 7 canines, 4 rabbits, and a monkey were used for these evaluations. Gray scale pulse inversion harmonic imaging of the LCs and the SLNs was performed after subcutaneous (n = 58), submucosal (n = 14), or parenchymal (n = 8) injections of a tissue-specific sonographic contrast agent (Sonazoid; GE Healthcare, Oslo, Norway). In many instances, blue dye was injected into the same locations as Sonazoid, and surgical dissection of the SLNs and LCs was performed for comparison. Scanning electron microscopy (SEM) of contrast-enhanced and control lymph nodes from 2 rabbits was performed to determine the mechanism of contrast agent uptake and retention within SLNs.

RESULTS

After subcutaneous, submucosal, or parenchymal contrast agent injections, gray scale pulse inversion harmonic imaging could be used to identify the number and location(s) of LCs and SLNs. After subcutaneous, submucosal, or parenchymal contrast agent injections, Sonazoid was confined to the SLNs (ie, contrast enhancement was not detected in the second-echelon nodes). There was good agreement between the results of lymphosonography and blue dye with surgical dissection in identifying the regional LCs and SLNs. Scanning electron microscopy identified vacuoles representing intact contrast microbubbles within contrast-enhanced SLN macrophages, which were not present in the control lymph nodes.

CONCLUSIONS

Lymphosonography can be used to detect lymphatic drainage pathways and SLNs in a variety of animal models.

[Study of the sentinel node in breast cancer using lymphoscintigraphy and a fast method for cytokeratin]

INTRODUCTION

Histopathological examination of the axillary sentinel node (SN) is becoming a routine procedure in the surgical phase of infiltrating ductal carcinoma of the breast (IDC). The SN exam may yield false negative cases mainly due to identification failure of the SN but some of the false negative cases may be the result of the pathological examination procedure applied.

MATERIAL AND METHODS

Sixty two (62) cases of clinically staged N0 IDC of the breast by TNM nomenclature were assigned to breast surgery along with conventional axillary node dissection. The identification technique included lymphoscintigraphy and intraoperative gamma-detecting probe after peritumoral injection of 99mTc-labeled colloids.The histological study of SN was performed with paired 4 microm slices and staining with hematoxylin-eosin and with a fast method of cytokeratins for freezing.

RESULTS

In only two of the 62 patients, it was not possible to identify the SN. Eighteen of the remaining 60 had SN involvement by metastasis, having no metastases in the other nodes of the axillary dissection in 6 of them. Ten of those were micrometastasis (size of metastasis= or <0.2 cm). In two out of these last 10 cases, diagnosis of the micrometastasis was only possible using slices stained with CK. There were no false negative results.

CONCLUSIONS

The lymphoscintigraphy, after peritumoral injection of small volumes and low dose of the tracer, makes it possible to obtain excellent results in the intraoperative detection of the SN in breast cancer. The study of this SN with a fast method for CK decreases the number of false negative results of the technique.