Evaluation of lymph node perfusion using continuous mode harmonic ultrasonography with a second-generation contrast agent

Role of Ultrasonography in Monitoring Chemotherapeutic Effects on Primary Thyroid Lymphoma: A Single-Center Retrospective Study

Background and Objectives: In this study, we assessed the utility of ultrasonography in monitoring the chemotherapeutic effects on primary thyroid lymphoma (PTL). Materials and Methods: This retrospective analysis included 17 patients with PTL who received chemotherapy from 2012 to 2022. The sonographic features were examined pre- and post-treatment using ultrasound (US) to monitor the treatment response at the first to second, third to fourth, and end cycles of chemotherapy and follow-up, and progression-free survival (PFS) and overall survival (OS) were analyzed. Results: The sonographic findings for all the patients indicated diffuse or nodular infiltration with markedly hypoechoic masses, and "stripe-shaped" high echoes and posterior acoustic enhancement were observed. Following one to two cycles of chemotherapy, a US examination revealed varying tumor reduction degrees and diminished blood flow signals. After three to four cycles of chemotherapy, the US demonstrated an evaluation efficacy comparable to that of PET-CT in cases in which the lesion had entirely disappeared postchemotherapy; however, its ability to differentiate between treatment response and residual lesions was less effective compared to that of PET-CT. After the end cycle of chemotherapy, the lesion sizes had significantly decreased compared to those at the baseline (p < 0.05). Postchemotherapy, Adler's blood flow grades decreased significantly, with 80% graded as 0-1. Among the 10 patients with cervical lymph node enlargement, 70% showed reduced lesion sizes and blood flow signals. The cumulative 5-year PFS and OS rates were both 80% for the diffuse type and 82.5% and 78.8% for the nodular type, respectively (p > 0.05). Conclusions: US can be utilized to monitor the therapeutic response following chemotherapy for PTL, especially for early assessment and repeated dynamic monitoring, and can serve as a complementary follow-up method to PET-CT.

Diagnostic value of contrast-enhanced ultrasound combined with serum procalcitonin in tuberculous lymph nodes and metastatic lymph nodes

OBJECTIVE

To investigate the value of Contrast-Enhanced Ultrasound (CEUS) combined with Procalcitonin (PCT) in differentiating Tuberculous Lymph Nodes (TLN) from Metastatic Lymph Nodes (MLN).

METHODS

This prospective cohort study included 207 consecutive patients diagnosed with CTL. All patients underwent routine ultrasound and CEUS prior to pathology or laboratory confirmation. Serum indicators were measured by Enzyme-Linked Immunosorbent Assay (ELISA). Predictive modeling was performed by multifactorial logistic regression. Evaluate the diagnostic and calibration performance of the predictive model by drawing Receiver Operating Characteristic (ROC) curves and calibration curves, and using Area Under the Curve (AUC) and Hosmer-Lemeshow (H-L) tests.

RESULTS

The diagnosis of MLN was confirmed pathologically or laboratory in 102 of 207 patients (49.27 %), and 50.8 % were confirmed to be TLN. According to imaging findings of CEUS, TLN was more commonly associated with enhanced concentric performance in the arterial phase (67.65 % vs. 40.95 %) and heterogeneous enhancement pattern in lymph nodes (70.59 % vs. 52.38 %). Peak Intensity (PI) of lesions was higher in patients with MLN. Increased age-enhanced concentric performance in the arterial phase, increased PI, and serum PCT greater than 5.39 ng/mL were independent risk factors for MLN. The prediction model of serum PCT combined with CEUS had a higher diagnostic value for MLN. The H-L test indicated a satisfactory model fit (all p > 0.05), and the calibration curve closely approximates the ideal diagonal.

CONCLUSION

CEUS combined with serum PCT has better clinical application value in the differential diagnosis of TLN and MLN.

Prospects of perfusion contrast-enhanced ultrasound (CE-US) in diagnosing axillary lymph node metastases in breast cancer: a comparison with lymphatic CE-US

Accurate diagnosis of lymph node (LN) metastasis is vital for prognosis and treatment in patients with breast cancer. Imaging 1modalities such as ultrasound (US), MRI, CT, and 18F-FDG PET/CT are used for preoperative assessment. While conventional US is commonly recommended due to its resolution and sensitivity, it has limitations such as operator subjectivity and difficulty detecting small metastases. This review shows the microanatomy of axillary LNs to enhance accurate diagnosis and the characteristics of contrast-enhanced US (CE-US), which utilizes intravascular microbubble contrast agents, making it ideal for vascular imaging. A significant focus of this review is on distinguishing between two types of CE-US techniques for axillary LN evaluation: perfusion CE-US and lymphatic CE-US. Perfusion CE-US is used to assess LN metastasis via transvenous contrast agent administration, while lymphatic CE-US is used to identify sentinel LNs and diagnose LN metastasis through percutaneous contrast agent administration. This review also highlights the need for future research to clarify the distinction between studies involving "apparently enlarged LNs" and "clinical node-negative" cases in perfusion CE-US research. Such research standardization is essential to ensure accurate diagnostic performance in various clinical studies. Future studies should aim to standardize CE-US methods for improved LN metastasis diagnosis, not only in breast cancer but also across various malignancies.

The value of nomogram model combined with contrast-enhanced ultrasound in the differential diagnosis of cervical tuberculosis lymphadenitis and metastatic lymph node

BACKGROUND

This study aimed to construct an effective Nomogram for the differential diagnosis of cervical tuberculosis lymphadenitis (CTBL) and cervical metastatic lymph node (CMLN) based on ultrasound (US).

METHODS

Retrospectively analyzed 227 patients with CTBL and CMLN who attended Hangzhou Red Cross Hospital from January 2020 to October 2022, and were divided into a training set (n = 163) and a validation set (n = 64) according to the clinical data, US, and CEUS qualitative and quantitative analysis data were recorded to establish the prediction model and perform validation. The area under curve (AUC) of the receiver operating characteristic curve (ROC) was used to assess the discrimination of the model; the calibration curve and brier coefficient were used to assess the calibration of the model; and a Nomogram prediction model was constructed to visualize the results nomogram prediction model was constructed to visualize the results.

RESULTS

Gender (OR = 0.200, 95% CI:0.090-0.470, P < 0.001), age (OR = 0.170, 95% CI:0.070-0.410, P < 0.001), liquefaction necrosis (OR = 2.560, 95% CI:1.080-6.040, P = 0.033), perfusion defect (OR = 2.570, 95% CI:1.010-6.580, P = 0.048), and standard deviation (StdDev) (OR = 3.040, 95% CI:1.220-7.570, P = 0.017) were the independent predictors of the constructed model. The AUCs of the constructed predictive model in the training set and validation set were 0.844 and 0.927, respectively; from the calibration curves, it was observed that the predicted values of the model and the actual observed values fell near the 45° diagonal, and the brier scores were 0.145 and 0.109 in the training set and validation set, respectively.

CONCLUSION

StdDev combined with gender, age, and the presence of liquefaction necrosis and perfusion defects are important features to identify CTBL and CMLN, and the constructed visual nomogram is intuitive and convenient to improve the efficiency of clinical work.

Diagnostic value of contrast-enhanced ultrasound for sentinel lymph node metastasis in breast cancer: an updated meta-analysis

PURPOSE

The status of sentinel lymph nodes (SLN) is an important factor in determining the stage of breast cancer (BC) and the surgical procedure, and also a biomarker of the BC prognosis. This meta-analysis was performed to investigate the diagnostic value of contrast-enhanced ultrasound (CEUS) for SLN metastasis.

METHODS

A systematic search was conducted for relevant articles published in the PubMed, Embase, Web of Science, OVID databases, and Cochrane Library from inception to March 2023. We calculated the sensitivity, specificity, positive and negative likelihood ratio (PLR; NLR), diagnostic odds ratio (DOR), and summary receiver operator characteristic (SROC) curve to evaluate the diagnostic efficacy of CEUS in SLN metastasis. Subgroup analysis was also performed to investigate potential sources of heterogeneity.

RESULTS

A total of 12 studies with 1525 patients were included in this meta-analysis. The overall pooled sensitivity and specificity of CEUS in the diagnosis of SLN metastasis were 0.91 (95% CI: 0.84-0.95) and 0.86 (95% CI: 0.78-0.92). The PLR, NLR, and DOR were 6.51 (95% CI: 4.09-10.36), 0.11 (95% CI: 0.07-0.18), and 59.43 (95% CI: 33.27-106.17), respectively, and the area under the SROC curve was determined to be 0.95 (95%CI: 0.92-0.96), all showing excellent diagnostic value. In the subgroup analysis, percutaneous CEUS was more sensitive than intravenous CEUS in the diagnosis of SLN metastases (0.92 versus 0.82, p < 0.05).

CONCLUSION

CEUS, especially percutaneous CEUS, is a reliable imaging technique for diagnosing SLN metastasis and providing important information in the stage management of breast cancer.

Quantitative evaluation of colorectal tumour vasculature using contrast-enhanced ultrasound: Correlation with angiogenesis and prognostic significance

BACKGROUND

Ultrasound is a vital tool for the diagnosis and management of colorectal cancer (CRC). Contrast-enhanced ultrasound (CEUS) is a non-invasive, safe, and cost-effective method for evaluating tumour blood vessels, that play a crucial role in tumour growth and progression.

AIM

To explore CEUS's role in the quantitative evaluation of CRC blood vessels and their correlation with angiogenesis markers and prognosis.

METHODS

This study prospectively enrolled 100 patients with CRC confirmed by histopathology. All patients received preoperative CEUS examinations. Quantitative parameters, such as peak intensity (PI), time to peak (TTP), and area under the curve (AUC), were derived from time-intensity curve (TIC) analysis. Tumour tissue samples were obtained during surgery and examined immunohistochemically to assess the expression of angiogenesis markers, including vascular endothelial growth factor (VEGF) and microvessel density (MVD). The correlation between CEUS parameters, angiogenesis markers, and clinicopathological features was evaluated using appropriate statistical tests.

RESULTS

Quantitative CEUS parameters (PI, TTP, and AUC) showed significant correlations with VEGF expression (P < 0.001) and MVD (P < 0.001), indicating a strong link between tumour blood vessels and angiogenesis. Increased PI, reduced TTP, and expanded AUC values were significantly related to higher tumour stage (P < 0.001), lymph node metastasis (P < 0.001), and distant metastasis (P < 0.001). Furthermore, these parameters were recognized as independent predictors of overall survival and disease-free survival in multivariate analysis (P < 0.001).

CONCLUSION

CEUS has a high potential in guiding treatment planning and predicting patient outcomes. However, more comprehensive, multicentre studies are required to validate the clinical utility of CEUS in CRC management.

Ultrasound imaging of the axilla

Axilla is a pyramidal-in-shape "virtual cavity" housing multiple anatomical structures and connecting the upper limb with the trunk. To the best of our knowledge, in the pertinent literature, a detailed sonographic protocol to comprehensively assess the axillary region in daily practice is lacking. In this sense, the authors have briefly described the anatomical architecture of the axilla-also using cadaveric specimens-to propose a layer-by-layer sonographic approach to this challenging district. The most common sonographic pathological findings-for each and every anatomical compartment of the axilla-have been accurately reported and compared with the corresponding histopathological features. This ultrasound approach could be considered a ready-to-use educational guidance for the assessment of the axillary region. CRITICAL RELEVANCE STATEMENT: Axilla is a pyramidal-in-shape "virtual cavity" housing multiple anatomical structures and connecting the upper limb with the trunk. The aim of this review article was to describe the anatomical architecture of the axilla, also using cadaveric specimens, in order to propose a layer-by-layer sonographic approach to this challenging district.

The findings on the CEUS of diffuse large B cell lymphoma in abdomen: A case report and literature review

Background

PET-CT is the first choice for the imaging diagnosis of intraperitoneal lymphomas. Contrast-enhanced ultrasound (CEUS) is rare in the diagnosis of intraperitoneal nodal lymphoma.

Case summary

A 62-year-old man was admitted for examination with "right upper abdominal pain". Ultrasound was used to refer to the masses in the hilar region, spleen, and anterior sacral region respectively. The masses were all hypoechoic, and blood flow signals could be detected by CDFI. Laboratory tests of CA125 were within normal limits. CEUS examination was performed on the three masses respectively. The three masses showed different perfusion patterns. Thickened vessels appeared around the mass in the hilar region, a peripheral centrally directed perfusion pattern was observed in the splenic mass, and blood supply vessels appeared in the center of the presacral mass with a significant filling defect. They all showed a contrast pattern with rapid clearance and hypoenhancement compared with the surrounding areas. Ultrasound guided needle biopsy revealed non-Hodgkin's lymphoma, diffuse large B-cell lymphoma, non-germinal center origin. After biopsy, the patient was treated with R-CHOP regimen for chemotherapy, and the tumor disappeared by routine ultrasound review after 5 cycles of chemotherapy.

Conclusion

To the best of our knowledge, this report is the first to describe the findings of CEUS in intraperitoneal nodal lymphoma. CEUS has various manifestations in intraperitoneal nodal lymphoma. Future studies are still needed to explore the diagnostic features of CEUS in intraperitoneal nodal lymphoma.

A combination of ultrasound and contrast-enhanced ultrasound improves diagnostic accuracy for the differentiation of cervical tuberculous lymphadenitis from primary lymphoma

OBJECTIVES

To present a method combining ultrasound (US) and contrast-enhanced ultrasound (CEUS) features for differential diagnosis of cervical tuberculous lymphadenitis (CTL) and primary lymphoma.

METHODS

A total of 155 patients with CTL (n = 49) and lymphoma (n = 106) who underwent US and CEUS were retrospectively included. The features extracted from US and CEUS and the significant clinical data were created three models using the least absolute shrinkage and selection operator and logistic regression analysis. The diagnostic performance of the models was assessed using the area under the curve (AUC).

RESULTS

The combined model outperformed US model and CEUS model in distinguish CTL from lymphoma achieved favorable performances in training set and validation set with AUCs of 0.958 and 0.946 as well as high accuracies (91.7% and 87.2%), sensitivities (95.9% and 84.4%) and specificities (82.4% and 93.3%). Delong's test showed that among the three models, combined model was significantly different from the other two models in training set (p = 0.011 and 0.029, respectively) and validation set (p = 0.018 and 0.001, respectively).

CONCLUSIONS

A combination of US and CEUS achieved good diagnostic performance in differentiating lymphoma and CTL, which might aid in clinical decision-making.

Comparison of microvascular flow imaging and contrast-enhanced ultrasound for blood flow analysis of cervical lymph node lesions

OBJECTIVE

To compare the diagnostic value of microvascular flow imaging (MVFI) with that of contrast-enhanced ultrasound (CEUS) for the analysis of blood flow in benign and malignant cervical lymph nodes.

MATERIAL AND METHODS

As a prospective study, 95 cervical enlarged lymph nodes (43 benign and 52 malignant) were observed in 95 patients using conventional ultrasonography (including gray and Color Doppler Flow Imaging), CEUS, and MVFI. Two researchers evaluated vascular parameters of MVFI (vascular distribution, internal vascular features, vascular index) and CEUS (enhancement mode, enhancement type) and compared the diagnostic effects of MVFI and CEUS.All results were compared with pathological findings.

RESULTS

There were significant differences in the vascular distribution and internal vascular features of benign and malignant lymph nodes on MVFI (P < 0.05). The vascular distribution of benign lymph nodes was mainly of the central and avascular types, the internal blood vessels were mostly normal, the vascular distribution of malignant lymph nodes was mainly mixed, the internal vessels were mainly tortuous and displaced. The optimal cut-off value of the benign and malignant lymph node vascular index (VI) was 15.55%, and the area under the receiver operating characteristic curve (AUC) of the VI was 0.876. There were also significant differences in the enhancement mode and types of benign and malignant lymph nodes in CEUS (P < 0.05). The benign lymph nodes showed centrifugal perfusion, and the enhancement types were mostly type I and type II. Most malignant lymph nodes showed centripetal or mixed perfusion, and the enhancement types were usually type III and type IV. The accuracy, sensitivity, and specificity of CEUS in the diagnosis of lymph node lesions were 84.2%, 84.6% and 83.7%, respectively, and the AUC was 0.845. The accuracy, sensitivity, and specificity of MVFI in the diagnosis of lymph node lesions were 85.3%, 84.6%, and 86.0%, respectively, and the AUC was 0.886.

CONCLUSION

Both CEUS and MVFI are valuable in differentiating benign and malignant lesions of lymph nodes and have a similar diagnostic performance; however, MVFI is less invasive and simpler than CEUS. Therefore it is preferred for auxiliary examination of enlarged lymph nodes that are difficult to diagnose by conventional ultrasound.

Correlation between physical characteristics of biopsy specimen and disease of cervical lymph node after contrast-enhanced ultrasound

Background

To investigate the correlation between physical characteristics and disease of cervical lymph node biopsy specimens after contrast-enhanced ultrasound.

Methods

All patients were biopsied after CEUS, 235 patients were divided into three groups A, B and C according to the physical characteristics of specimens: 92 patients in group A were complete tissue specimens; 113 patients in group B were discontinuous tissue specimens. There were 30 patients in group C, including a small number of tissue and floc, purulent and bloody specimens. Pathological examination, pathogen culture examination and Gene X-Pert MIB examination were completed for all patients in the three groups, and statistical analysis was conducted on the integrity and traits of the specimens.

Results

Group A included 92 intact tissue specimens, 21 with reactive hyperplasia, 17 with lymphoma, 12 with metastatic carcinoma, 13 with lymphadenopathy, 15 with necrotizing lymphadenitis, and rare lymphadenopathy. In group B, 113 patients were treated with intermittent tissue specimens, including infected lymph nodes, lymphoma in 1 case, metastatic carcinoma in 3 cases and sarcoidosis in 1 case. There were 30 patients in group C, including a small amount of tissue and floc, purulent and bloody specimens, all of which were infected lymph nodes. The χ² value of malignant and benign lymph nodes was 42.401, p = 0.000.

Conclusion

The physical characteristics of cervical lymph node biopsy specimens after CEUS are correlated with the disease, which has guiding significance for postoperative specimen selection.

Contrast-enhanced and microvascular ultrasound imaging features of testicular lymphoma: report of five cases and review literature

Background

To retrospectively investigate the grey-scale, Doppler, contrast-enhanced and microvascular ultrasound of five patients with primary testicular lymphoma of our institute through review literature analysis.

Methods

From January to November 2020, five patients with primary testicular lymphoma confirmed by histology were preoperatively investigated with a standardized sonographic protocol including contrast-enhanced and microvascular ultrasound.

Results

Conventional ultrasound showed localized hypoechogenicity represented with solitary (2 of 5), multiple lesions (2 of 5), or entire testicular involvement (1 of 5). Increased blood flow appeared in color Doppler ultrasound with straight vascular sign (4 of 5). In contrast-enhanced ultrasound images confirmed this pattern (4 of 5) and presented hyper enhancement with enlarged range. On microvascular ultrasound imagings, all lesions were presented with straight and parallel course of intralesional vessels (5 of 5).

Conclusions

Here, we identified an increased vascularity with enlarged range on contrast-enhanced ultrasound along with a linear nonbranching pattern by vascular sign on microvascular ultrasonographic of testicular lymphoma.

The value of multimodal ultrasonography in differential diagnosis of tuberculous and non-tuberculous superficial lymphadenitis

Background

To investigate the value of multimodal ultrasonography in differentiating tuberculosis from other lymphadenopathy.

Methods

Sixty consecutive patients with superficial lymphadenopathy treated at our hospital from January 2017 to December 2018 were categorized into four types based on the color Doppler ultrasound, five types based on contrast-enhanced ultrasound, and five types based on elastography. Sensitivity and specificity were calculated of all the three imaging, including color Doppler examination, contrast-enhanced ultrasound and one individual multimodal method, for detecting lymph nodes.

Results

A total of 60 patients were included in the final analysis. Of those, Mycobacterium tuberculosis was positive in 38 patients and negative in 22 patients. Among the 38 patients who were positive for Mycobacterium tuberculosis, of which 23 had a history of pulmonary tuberculosis, accounting for 60.53% of the positive cases, and the remaining patients did not combine lesions of other organs. Among the 60 superficial lymph nodes, 63.3% presented with tuberculous lymphadenitis. The sensitivity, specificity, and accuracy of the color Doppler examination were 73.68%, 68.18%, and 71.67%, respectively. The sensitivity, specificity and accuracy of contrast-enhanced ultrasound were 89.47%, 63.64% and 80.00%, respectively. The sensitivity, specificity and accuracy of the elastography were 63.16%, 63.64% and 63.33%, respectively. The sensitivity, specificity and accuracy of one individual multimodal method were 42.11%, 95.45% and 61.67%, respectively. The sensitivity, specificity and accuracy of all modes combined were 100.00%, 27.27% and 73.33%, respectively.

Conclusion

Multimodal ultrasonography has high predictive value for the differential diagnosis of superficial tuberculous lymphadenitis.

Comparison of the value of ultrasound and enhanced magnetic resonance imaging in judging cervical lymph node metastasis in patients with oral cancer

BACKGROUND

Oral cancer is the twelfth largest malignant tumor in the world. Oral cancer is prone to lymph node metastasis in the early stages of the disease, and lymph node metastasis will directly affect the treatment and survival rate. Therefore, whether the lymph node metastasis can be accurately evaluated is of great significance to the treatment and prognosis of patients.

OBJECTIVE

The diagnostic efficacy of three methods of preoperative ultrasound, enhanced magnetic resonance (enhanced MR), and ultrasound combined with enhanced MR on cervical lymph node metastasis of oral cancer were compared.

MATERIALS AND METHODS

A retrospective analysis of 399 cases of oral cancer completed by head and neck surgery at Cancer Center of Sun Yat-sen University, China. In all cases, the maxillofacial and neck enhanced MR and cervical lymph node ultrasound examinations were performed before surgery, and imaging diagnosis was made for cervical lymph node metastasis and compared with pathology. All judgment results were statistically processed using the chi-square test.

RESULTS

Compared with the above three methods, the diagnostic efficiency of ultrasound alone is better, and the diagnostic efficiency of enhanced MR combined ultrasound is not significantly better than that of ultrasound alone. There are differences in the diagnostic efficacy of the three inspection methods in different clinical sub-periods, all of which are better for the diagnosis of stage I. For patients with stage I, II, and III, there were no differences between the three examination methods. However, for stage IV patients,the diagnostic efficiency of ultrasound alone is better. For patients with stage N0, there was no difference in diagnostic efficacy between the three methods. For the assessment of lymph nodes in the I-III region, there are differences between the three methods of examination: the diagnostic efficiency of ultrasound alone is better, and enhanced MR combined ultrasound is not significantly better than ultrasound alone. For the evaluation of lymph nodes in the IV-VII region, there was no difference in diagnostic efficacy between the three methods.

CONCLUSION

According to the clinical characteristics and prognosis of patients with oral cancer, although enhanced MR can better evaluate the tumor, ultrasound may be considered as the preferred imaging method for cervical lymph node metastasis.

SIGNIFICANCE

Accurate assessment and proper and timely treatment of lymph node metastasis can help improve the survival rate of patients.

Clinical Research of Combined Application of DCEUS and Dynamic Contrast-Enhanced MSCT in Preoperative cT Staging of Gastric Cancer

Purpose

To investigate the clinical value of double contrast-enhanced ultrasound (DCEUS) combined with dynamic contrast-enhanced multislice CT (MSCT) in preoperative T staging of gastric cancer (GC).

Methods

206 patients with GC confirmed by preoperative gastroscopy from February 2019 to February 2021 were collected, all patients were examined by DCEUS and dynamic contrast-enhanced MSCT before operation, and the invasion depth (T staging) of GC was evaluated. The diagnosis results of DCEUS, dynamic contrast-enhanced MSCT, and combined diagnosis of DCEUS and MSCT methods (D&M method) were compared with the pathological staging results (gold standard).

Results

The correct diagnosis rate of MSCT was 27.27% in T1 staging, 55.56% in T2 staging, 42.11% in T3 staging, 59.29% in T4 staging, and 55.34% in summation. The correct diagnosis rate of DCEUS was 90.91% in T1 staging, 88.89% in T2 staging, 78.95% in T3 staging, 82.86% in T4 staging, and 83.98% in summation. The correct diagnosis rate of the D&M method was 100.00% in T1 staging, 94.44% in T2 staging, 89.47% in T3 staging, 93.57% in T4 staging, and 93.69% in summation. The D&M method had higher correct diagnosis rate than MSCT or DCEUS alone, the correct diagnosis rate of the D&M method in T1, T2, T3, and T4 staging was significantly higher than that of MSCT (P < 0.05). The correct diagnosis rate of the D&M method in T1, T3, and T4 was significantly higher than that of DCEUS (P < 0.05). The Youden index of preoperative T1, T2, T3, and T4 staging of GC by the D&M method was 99.49%, 94.44%, 84.13%, and 90.54%, respectively, and the Kappa values of these were 0.954, 0.966, 0.707, and 0.881, respectively.

Conclusions

Dynamic contrast-enhanced MSCT combined with DCEUS in the diagnosis of preoperative cT staging of GC has more validity, reliability, and revenue than the using of MSCT or DCEUS alone, which is an image evaluation method worthy of clinical promotion.

Characterizing perfusion defects in metastatic lymph nodes at an early stage using high-frequency ultrasound and micro-CT imaging

A perfusion defect in a metastatic lymph node (LN) can be visualized as a localized area of low contrast on contrast-enhanced CT, MRI or ultrasound images. Hypotheses for perfusion defects include abnormal hemodynamics in neovascular vessels or a decrease in blood flow in pre-existing blood vessels in the parenchyma due to compression by LN tumor growth. However, the mechanisms underlying perfusion defects in LNs during the early stage of LN metastasis have not been investigated. We show that tumor mass formation with very few microvessels was associated with a perfusion defect in a non-enlarged LN at the early stage of LN metastasis in a LN adenopathy mouse (LN size circa 10 mm). We found in a mouse model of LN metastasis, induced using non-keratinizing tumor cells, that during the formation of the perfusion defect in a non-enlarged LN, the number of blood vessels ≤ 50 μm in diameter decreased, while those of > 50 μm in diameter increased. The methods used were contrast-enhanced high-frequency ultrasound and contrast-enhanced micro-CT imaging systems, with a maximum spatial resolution of > 30 μm. Furthermore, we found no tumor angiogenesis or oxygen partial pressure (pO₂) changes in the metastatic LN. Our results demonstrate that the perfusion defect appears to be a specific form of tumorigenesis in the LN, which is a vascular-rich organ. We anticipate that a perfusion defect on ultrasound, CT or MRI images will be used as an indicator of a non-enlarged metastatic LN at an early stage.

Oncologic Imaging of the Lymphatic System: Current Perspective with Multi-Modality Imaging and New Horizon

The lymphatic system is an anatomically complex vascular network that is responsible for interstitial fluid homeostasis, transport of large interstitial particles and cells, immunity, and lipid absorption in the gastrointestinal tract. This network of specially adapted vessels and lymphoid tissue provides a major pathway for metastatic spread. Many malignancies produce vascular endothelial factors that induce tumoral and peritumoral lymphangiogenesis, increasing the likelihood for lymphatic spread. Radiologic evaluation for disease staging is the cornerstone of oncologic patient treatment and management. Multiple imaging modalities are available to access both local and distant metastasis. In this manuscript, we review the anatomy, physiology, and imaging of the lymphatic system.

Contrast-enhanced ultrasound imaging for intestinal lymphoma

BACKGROUND

Intestinal lymphoma is a rare tumor. Contrast-enhanced ultrasound (CEUS) findings of intestinal lymphoma have not been reported previously, and the relationship between CEUS and clinicopathological features and prognostic factors is still unknown.

AIM

To describe the B-mode US and CEUS features of intestinal lymphoma and investigate the correlation of CEUS and histopathological features.

METHODS

This was a single-center retrospective study. Eighteen patients with histologically confirmed intestinal lymphoma underwent B-mode US and CEUS examinations between October 2016 and November 2019. We summarized the features of B-mode US and CUES imaging of intestinal lymphoma and compared the frequency of tumor necrosis in intestinal lymphomas with reference to different pathological subtypes (aggressive or indolent) and clinical stage (early or advanced). The time-intensity curve parameters of CEUS were also compared between patients with normal and elevated serum lactate dehydrogenase.

RESULTS

In B-mode imaging, four patterns were observed in intestinal lymphoma: Mass type (12/18, 66.7%), infiltration type (1/18, 5.6%), mesentery type (4/18, 22.2%) and mixed type (1/18, 5.6%). All cases were hypoechoic and no cystic areas were detected. On CEUS, most cases (17/18, 94.4%) showed arterial hyperechoic enhancement. All cases showed arterial enhancement followed by venous wash out. A relatively high rate of tumor necrosis (11/18, 61.1%) was observed in this study. Tumor necrosis on CEUS was more frequent in aggressive subtypes (10/13, 76.9%) than in indolent subtypes (1/5, 20.0%) (P = 0.047). There were no correlations between tumor necrosis and lesion size and Ann Arbor stage. There was no significant difference in time-intensity curve parameters between normal and elevated lactate dehydrogenase groups.

CONCLUSION

B-mode US and CEUS findings of intestinal lymphoma are characteristic. We observed a high rate of tumor necrosis, which appeared more frequently in aggressive pathological subtypes of intestinal lymphoma.

Comparative study of two contrast agents for intraoperative identification of sentinel lymph nodes in patients with early breast cancer

Background

The use of contrast-enhanced ultrasound (CEUS) to locate sentinel lymph nodes (SLNs) in breast cancer has been studied more and more in recent years. This prospective study aimed to compare periareolar injection of two different contrast agents, SonoVue^® (SNV) and Sonazoid^® (SNZ), followed by CEUS to identify SLNs in breast cancer patients with clinically negative nodes.

Methods

A total of 205 patients with T1-2N0M0 breast cancer were divided into the SNV group and SNZ group. All were administered a periareolar injection of SNV or SNZ and underwent US to identify contrast-enhanced SLNs. Each contrast-enhanced SLN underwent a biopsy with blue dye and examined again by CEUS in vitro.

Results

In all cases, contrast-enhanced lymphatic vessels were clearly visualized using US soon after the periareolar injection of SNZ, and the SLNs were easily identified. The SLN identification rates were 75.27% (210/279) for SNV and 93.58% (102/109) for SNZ. Although the accuracy of detecting SLN metastasis was slightly different between the two groups, there was no statistically significant difference between those groups (P=0.615). Moreover, it was possible to identify SLNs in vitro in the SNZ group, and these could be compared with the lymph nodes (LNs) located using SNZ during the preoperative stage and with blue dye during the procedure. This helped in determining the resection requirements.

Conclusions

When comparing the subdermal use of SNV and SNZ, no significant differences in the number of detected SLNs and the diagnosis of metastatic LNs were observed. Because SLNs can be detected for a longer time in living tissues with SNZ, this contrast agent may provide more intraoperative information for complete resection of all preoperative localization of SLN.

Lymph Node Ultrasound in Lymphoproliferative Disorders: Where Are We Now?

Lymphoproliferative disorders are one of the most frequent hematological malignancies affecting the blood and lymphatic system. To better stratify patients, an accurate imaging evaluation is needed. Although computed tomography and positron emission tomography are considered the standard methods, these procedures have several clinical drawbacks, such as biological risk and high costs. Ultrasound (US) is a rapid and user-friendly method to evaluate lymph node (LN) and organ enlargements. US imaging provides more sensitive information about LN structure, vascularization, and metabolism and new techniques have increased its specificity, especially in malignant setting. However, validated and standardized criteria for its use are missing, with only several single-center experiences reported. Therefore, the aim of this paper is to review and briefly illustrate the status of the US knowledge and applications in lymphoproliferative workup, particularly concerning malignant LN pathology.

Contrast-enhanced ultrasound of the small organs in children

In pediatric and adult populations, intravenous contrast-enhanced ultrasound (CEUS) remains off-label for imaging of organs other than the liver and heart. This limited scope inhibits potential benefits of the new modality from a more widespread utilization. Yet, CEUS is potentially useful for imaging small organs such as the thyroid gland, lymph nodes, testes, ovaries and uterus, with all having locations and vasculature favorable for this type of examination. In the adult population, the utility of CEUS has been demonstrated in a growing number of studies for the evaluation of these small organs. The aim of this article is to present a review of pediatric CEUS of the thyroid gland, lymph nodes, testes, ovaries and uterus as well as to draw from the adult literature indications for possible applications in children.

Utility of quantitative contrast-enhanced ultrasound for the prediction of lymph node metastasis in patients with papillary thyroid carcinoma

OBJECTIVES

The aim of this study was to find the optimal parameters and cutoffs to differentiate metastatic lymph nodes (LNs) from benign LNs in the patients with papillary thyroid carcinoma (PTC) on the quantitative contrast-enhanced ultrasound (CEUS) features.

METHODS

A total of 134 LNs in 105 patients with PTCs were retrospectively enrolled. All LNs were evaluated by conventional ultrasound (US) and CEUS before biopsy or surgery. The diagnostic efficacy of CEUS parameters was analyzed.

RESULTS

Univariate analysis indicated that metastatic LNs more often manifested centripetal or asynchronous perfusion, hyper-enhancement, heterogeneous enhancement, ring-enhancing margins, higher PI, larger AUC, longer TTP and DT/2 than benign LNs at pre-operative CEUS (p <  0.001, for all). Multivariate analysis showed that centripetal or asynchronous perfusion (OR = 3.163; 95% CI, 1.721-5.812), hyper-enhancement(OR = 0.371; 95% CI, 0.150-0.917), DT/2 (OR = 7.408; 95% confidence interval CI, 1.496-36.673), and AUC (OR = 8.340; 95% CI, 2.677-25.984) were predictive for the presence of metastatic LNs. The sensitivity and accuracy of the quantitative CEUS were higher than qualitative CEUS (75% vs 55 % and 83.6% vs 76.1 % , respectively).

CONCLUSIONS

Quantitative CEUS parameters can provide more information to distinguish metastatic from benign LNs in PTC patients; In particular, DT/2 and AUC have a higher sensitivity and accuracy in predicting the presence of metastatic LNs and reduce unnecessary sampling of benign LNs.

Role of Contrast-Enhanced Ultrasound (CEUS) in the Diagnosis of Cervical Lymph Node Metastasis in Nasopharyngeal Carcinoma (NPC) Patients

Objective: The aim of the study was to evaluate the diagnostic value of contrast-enhanced ultrasound (CEUS) in distinguishing between benign and malignant cervical lymph nodes in patients with nasopharyngeal carcinoma (NPC).

Material and Methods: A total of 144 NPC patients with enlarged superficial cervical lymph nodes underwent CEUS examination. The comparison of CEUS image characteristics between malignant and benign cervical lymph nodes was performed in this study as well. We analyzed parameters of the time–intensity curve (TIC), which includes time to peak (TP), area under the gamma curve (AUC), and peak intensity (PI). Furthermore, receiver operating characteristic (ROC) curve analysis was also investigated to evaluate the diagnostic value of CEUS.

Result: We conducted 144 lymph node examinations in total, where 64 cases were biopsy-proven benign nodules and 80 cases were biopsy-proven metastatic nodules. The vast majority of the benign nodes displayed centrifugal perfusion (96.88%, 62/64) and homogeneous enhancement (93.75%, 60/64), while most of the malignant nodes showed centripetal perfusion (92.50%, 74/80) and inhomogeneous 80.00% (64/80). In addition, quantitative analysis showed that CEUS parameters including PI, TP, and AUC in benign lymph nodes (12.51 ± 2.15, 23.79 ± 11.80, and 1110.33 ± 286.17, respectively) were significantly higher than that in the malignant nodes (10.51 ± 2.98, 16.52 ± 6.95, and 784.09 ± 340.24, respectively). The assistance of the three aforementioned parameters and CEUS image characteristics would result in an acceptable diagnostic value.

Conclusion: Our results suggest that imaging perfusion patterns as well as quantitative parameters obtained from CEUS provide valuable information for the evaluation of cervical lymph nodes in NPC patients.

[CME Sonography 92: Nodes on the Neck]

CME Sonography 92: Nodes on the Neck Abstract. Nodules on the neck can be discovered accidentally when looking in the mirror, or due to pain that may be acute or gradual. The clinical examination is helpful to estimate the localization or to assign the nodule to a specific organ and assess its consistency and mobility. A sonography is very helpful in most cases as there are typical findings related to the thyroid gland, findings based on lymph nodes, changes in the tonsils, vessels and salivary glands. In some cases, the ultrasound must be supplemented by fine needle puncture.

Comparison of contrast-enhanced ultrasound and contrast-enhanced computed tomography for the diagnosis of cervical lymph node metastasis in squamous cell carcinoma of the oral cavity

Early detection of cervical lymph node metastasis (CLNM) from squamous cell carcinoma (SCC) of the oral cavity remains challenging. This prospective study was performed to evaluate the ability of contrast-enhanced ultrasound (CEUS) to detect CLNM from oral cavity SCC. Additionally, its diagnostic value was compared with that of contrast-enhanced computed tomography (CECT). Forty-eight consecutive patients with SCC of the oral cavity were enrolled. All subjects were examined preoperatively with both CEUS and CECT. Subsequently, neck dissections were performed for these patients, and cervical lymph nodes separated from the surgical specimens were assessed histologically. The diagnostic performance of these two examinations was compared based on the results of histopathology. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and Youden index for CEUS and CECT were 69.39% vs. 44.90%, 94.71% vs. 97.12%, 89.88%% vs. 87.16%, 75.56% vs. 78.57%, 92.92% vs. 88.21%, and 64.10% vs. 42.02%, respectively. A significant difference was observed in terms of sensitivity (P=0.024) and Youden index (rate difference 22.08%, 95% confidence interval 2.72-41.44%). Therefore, CEUS appears to be a promising diagnostic tool that is superior to CECT for detecting CLNM from SCC of the oral cavity, with a higher sensitivity.

The Value of CEUS in Distinguishing Cancerous Lymph Nodes From the Primary Lymphoma of the Head and Neck

Aim: The purpose of this study was to assess the ability of contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of cancerous lymph nodes.

Methods: Contrast-enhanced ultrasonography was performed in the cervical nodules of included patients, and the diagnoses were confirmed by pathological examination. Contrast-enhanced ultrasonography images and parameters of head and neck lymphomas were compared with those of cancerous lymph nodes. Besides, receiver operating characteristic curve was operated to access the diagnostic value of CEUS.

Results: Finally, a total of 63 head and neck lymphomas and 80 cervical cancerous lymph nodes were enrolled in this study. Results showed that the CEUS images of lymphoma were mainly characterized by homogeneous enhancement (71.43%), and approximately half of them were centripetal perfusion (58.73%), whereas most CEUS images of cancerous lymph nodes were inhomogeneous enhancement (82.50%) and centripetal perfusion (92.50%). Quantitative analysis of CEUS parameters indicated that PI (derived peak intensity) and AUC (area under the curve) of lymphomas were both lower than those of cancerous lymph nodes (PI: 8.78 vs. 10.51, AUC: 652.62 vs. 784.09, respectively) (P < 0.05). Receiver operating characteristic analysis showed that the sensitivity of CEUS parameters in the differential diagnosis was significant (80.00%), although the specificity was not high (47.62%). When parameters were combined with the image features, the accuracy of diagnosis was greatly improved (from 0.655 to 0.899).

Conclusion: Contrast-enhanced ultrasonography could be a promising tool for the differential diagnosis of head and neck lymphomas and cancerous lymph nodes.

Homogeneity Parameter in Contrast-Enhanced Ultrasound Imaging Improves the Classification of Abnormal Cervical Lymph Node after Thyroidectomy in Patients with Papillary Thyroid Carcinoma

Objective

To explore the conventional and contrast-enhanced ultrasound (CEUS) features of cervical lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC) patients postoperatively and analyze its pathological basis.

Materials and Methods

Conventional and CEUS were performed in 86 abnormal cervical lymph nodes (ACLNs) from 56 PTC patients who had received thyroidectomy. Then, fine-needle aspiration (FNA) was taken to confirm pathological results, a multivariate analysis was performed to correlate the sonographic features of the CLNM, and then an equation for CLNM was established.

Results

Fifty-four lymph nodes were confirmed to be metastasis of PTC by FNA. Intensity at peak time, homogeneity, and color flow patterns, cystic change, or microcalcification and echogenicity were significantly associated with CLNM. Multivariate analysis showed three strongest features (homogeneity, intensity of peak, and cystic change or calcification) to be significantly associated with the evidence of CLNM. Then, the equation was established with the following significant predictive factors: P = 1/1 + exp∑[−3.213 + 2.77 ∗ cystic or calcification + 0.13 ∗ CDFI patterns + 3.65 ∗ homogeneity + 2.43 ∗ intensity at peak time].

Conclusion

Depiction of a heterogeneous hyperenhancement of cervical lymph nodes within CEUS studies and cystic change or microcalcification in conventional ultrasound were identified as predictive for metastatic lymph node invasion, and the equation was more accurate for predicting CLNM compared to single B-mode ultrasound and CEUS feature.

Percutaneous contrast-enhanced ultrasound for localization and diagnosis of sentinel lymph node in early breast cancer

This study assessed the efficacy of percutaneous contrast-enhanced ultrasound (CEUS) in localization sentinel lymph node (SLNs) for biopsy and diagnosis of metastatic SLNs in patients with early breast cancer. From January to November 2017, seventy-five patients with early breast cancer confirmed by pathology were enrolled in this study. CEUS was performed after subdermal injection of ultrasound contrast agent (SonoVue, 2.0 ml in total dose) around the areola on the ipsilateral side of the breast. The contrast-enhanced lymphatic vessels and associated SLNs were observed and traced in real time. The lymphatic vessels and SLN were mapped and labeled on the skin surface. Sentinel lymph node biopsy (SLNB) was performed after injection of 2.0 ml methylene blue at same injection site of SonoVue. The accuracy of percutaneous CEUS localization of SLNs was determined compared to blue dye injection technique. The pathological results under blue dye guided biopsy were used as the reference standard to calculate the sensitivity and specificity of CEUS for the diagnosis of SLNs. A total of 163 SLNs obtained through SLNB following methylene blue tracing in 75 patients. There were 116 SLNs identified by percutaneous CEUS. The difference of detection rates between blue dye and CEUS was statistically significant (Z = -2.651, P = 0.008). The identification rate of SLNs by CEUS was 71.17% (116/163). The accuracy of percutaneous CEUS localization of axillary SLNs was 94.67% (71/75) compared to blue dye-guided biopsy. Among the 116 SLNs detected by percutaneous CEUS, pathologic results showed 51 positive SLNs and 65 negative SLNs whiles CEUS findings indicated 83 positive SLNs and 33 negative SLNs. Only 50 of 83 SLNs had metastasis on pathology, while 33 were detected as false positive. The sensitivity and specificity of CEUS for the diagnosis of metastatic SLN was 98.04%(50/51) and 49.23%(32/65), respectively. Percutaneous CEUS can be used as an effective method to localize the SLNs for guiding SLNB. This method has excellent sensitivity for identifying the SLNs but lower specificity for detecting metastatic SLNs in patients with early stage breast cancer.

Double Contrast-Enhanced Ultrasonography in Preoperative T Staging of Gastric Cancer: A Comparison With Endoscopic Ultrasonography

Objective: To compare the precision of double contrast-enhanced ultrasonography (DCEUS) to endoscopic ultrasonography (EUS) in preoperative T staging of gastric cancers.

Methods: This retrospective study consisted of 158 pathologically confirmed gastric cancer patients. All patients underwent DCEUS (intravenous contrast-enhanced ultrasonography combined with oral contrast-enhanced ultrasonography) and endoscopic ultrasonography (EUS) preoperatively. The histopathological findings of resected specimens were compared with the results of DCEUS and EUS retrospectively.

Results: The accuracy of DCEUS and EUS in evaluating the T staging of gastric cancer were 82.3% (T1 62.5%,T2 84.4%,T3 87.9%,T4 91.3%) and 76.6% (T1 84.4%,T2 82.2%,T3 72.4%,T4 65.2%), respectively. There were no significant differences between the methods for the overall T staging accuracy (χ² = 1.569, P = 0.210). But EUS was superior to DCEUS for T1 stage (χ² = 3.925, P = 0.048) and DCEUS was superior to EUS for T3 stage (χ² = 4.393, P = 0.036) and T4 stage (χ² = 4.600, P = 0.032).

Conclusion: DCEUS is a convenient and noninvasive method with high precision, which can be used as the primary imaging technique for advanced gastric cancer T staging. In early gastric cancer, we should prefer EUS. Two methods are complementary for assessing tumor invasion depth of gastric cancer.

Predictive Factors for Inaccurate Diagnosis of Swollen Lymph Nodes in Endoscopic Ultrasound-Guided Fine Needle Aspiration

Background/Aims

This study aimed to identify the predictive factors for inaccurate endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) diagnosis of swollen lymph nodes without rapid on-site cytopathological evaluation.

Methods

Eighty-three consecutive patients who underwent EUS-FNA for abdominal or mediastinal lymph nodes from January 2008 to June 2017 were included from a prospectively maintained EUS-FNA database and retrospectively reviewed. The sensitivity, specificity, and accuracy of EUS-FNA for the detection of neoplastic diseases were calculated. Candidate factors for inaccurate diagnosis (lymph node size and location, needle type, puncture route, number of passes, and causative disease) were evaluated by comparison between accurately diagnosed cases and others.

Results

The final diagnosis of the punctured lymph node was classified as neoplastic (65 cases: a metastatic lymph node, malignant lymphoma, or Crow-Fukase syndrome) or non-neoplastic (18 cases: a reactive node or amyloidosis). The sensitivity, specificity, and accuracy were 83%, 94%, and 86%, respectively. On multivariate analyses, small size of the lymph node was the sole predictive factor for inaccurate EUS-FNA diagnosis with a significant difference (odds ratios, 19.8; 95% confidence intervals, 3.15–124; p=0.0015).

Conclusions

The lymph node size of <16 mm was the only independent factor associated with inaccurate EUS-FNA diagnosis of swollen lymph nodes.

Comparison of Contrast-Enhanced Ultrasound and Positron Emission Tomography/Computed Tomography (PET/CT) in Lymphoma

Background

This study aimed to assess the value of contrast-enhanced ultrasound (CEUS) in the diagnosis and prognosis of lymphoma based on PET-CT.

Material/Methods

Our study included 88 superficial lymph nodes and 63 patients who underwent ultrasound-guided biopsy or surgery for pathology from October 2015 to March 2017. All lymph nodes were assessed by CEUS and PET-CT. CEUS and PET-CT parameters were recorded, including arrive time (AT), time to peak (TTP), base intensity (BI), peak intensity (PI), ascending slope (AS), descending slope (DS), area under the TIC curve (AUC), maximum standardized uptake value (SUVmax), and mean standardized uptake value (SUVmean). Pearson’s correlation was used to assess the associations of CEUS and PET-CT parameters.

Results

Of the 88 lymph nodes examined,12 were Hodgkin’s lymphoma (HL) and76 were non-Hodgkin’s lymphoma (NHL). The variations of CEUS dose parameters (ΔI, AUC, and AS) were positively correlated with PET-CT results (SUVmax and TLG). Correlation coefficients were 0.609, 0.518, 0.456, 0.630, 0.593, and 0. 532, respectively. The remaining time values (AT, TP, and ΔT) were negatively associated with PET-CT results. Correlation coefficients were −0.239, −0.272, −0.284and −0.377, −0.391, and −0.320, respectively.

Conclusions

Quantitative CEUS data were correlated with PET-CT values, with potential use in the diagnosis of lymphoma.

Multimodal photoacoustic imaging as a tool for sentinel lymph node identification and biopsy guidance

As a minimally invasive method, sentinel lymph node biopsy (SLNB) in conjunction with guidance methods is the standard method to determine cancer metastasis in breast. The desired guidance methods for SLNB should be capable of precise SLN localization for accurate diagnosis of micro-metastases at an early stage of cancer progression and thus facilitate reducing the number of SLN biopsies for minimal surgical complications. For this, high sensitivity to the administered dyes, high spatial and contrast resolutions, deep imaging depth, and real-time imaging capability are pivotal requirements. Currently, various methods have been used for SLNB guidance, each with their own advantages and disadvantages, but no methods meet the requirements. In this review, we discuss the conventional SLNB guidance methods in this perspective. In addition, we focus on the role of the PA imaging modality on real-time SLN identification and biopsy guidance. In particular, PA-based hybrid imaging methods for precise SLN identification and efficient biopsy guidance are introduced, and their unique features, advantages, and disadvantages are discussed.

Analysis of Contrast-Enhanced Ultrasound Perfusion Patterns and Time-Intensity Curves for Metastatic Lymph Nodes From Lung Cancer: Preliminary Results

OBJECTIVES

To retrospectively summarize the similarities and differences in contrast-enhanced ultrasound (US) findings for lymph node metastasis from adenocarcinoma, squamous carcinoma, and small cell lung cancer.

METHODS

Patients who had received contrast-enhanced US examinations and had a histologic diagnosis of supraclavicular lymph node metastasis from lung cancer were included. The perfusion patterns on contrast-enhanced US images and time-intensity curve parameters were analyzed for the different pathologic types. The microvascular density and microvascular diameter were evaluated.

RESULTS

Totally, 61 patients were enrolled in this study, including 26 cases with lung squamous carcinoma, 26 with lung adenocarcinoma, and 9 with small cell lung cancer. Contrast-enhanced US perfusion showed no significant differences in enhancement uniformity during the arterial phase and in the presence of unenhanced areas of metastatic lymph nodes with the 3 different pathologic origins (P > .05), but fewer unenhanced areas could be seen in metastatic lymph nodes from adenocarcinoma. The analysis of the time-intensity curve parameters showed that there were significant differences in the peak intensity between metastatic lymph nodes from lung squamous carcinoma and lung adenocarcinoma (P < .05). The microvascular density of metastatic lymph nodes from adenocarcinoma was significantly higher than that of metastatic lymph nodes from squamous carcinoma and small cell lung cancer (P < .001; P = .0444), whereas the microvascular diameter of metastatic lymph nodes from adenocarcinoma was significantly smaller than that from squamous carcinoma and small cell lung cancer (P = .0277; P < .001).

CONCLUSIONS

Effects of the pathologic diagnosis should be considered when analyzing quantitative parameters of metastatic lymph nodes during contrast-enhanced US examinations, even in the same organ.

The role of CEUS in characterization of superficial lymph nodes: a single center prospective study

Accurate lymph node characterization is important in a large number of clinical settings. We evaluated the usefulness of Contrast Enhanced Ultrasound (CEUS) in distinguishing between benign and malignant lymph nodes compared with conventional ultrasonography in the differential diagnosis of superficial lymphadenopathy.

We present our experience for 111 patients enrolled in a single center.

111 superficial lymph nodes were selected and only 1 lymph node per patient underwent CEUS. A definitive diagnosis for all lymph nodes was obtained by ultrasonographically guided biopsy and/or excision biopsy.

The size of the lymph nodes, the site (neck, axilla, inguinal region) being easily accessible for biopsy, and the US and color Doppler US characteristics guided us in selecting the nodes to be evaluated by CEUS.

In our study we identified different enhancement patterns in benign and malignant lymph nodes, with a high degree of diagnostic accuracy for superficial lymphadenopathy in comparison with conventional US.

Diagnostic Value of Contrast-Enhanced Ultrasonography and Time-Intensity Curve in Differential Diagnosis of Cervical Metastatic and Tuberculous Lymph Nodes

OBJECTIVES

To evaluate the diagnostic value of contrast-enhanced ultrasonography (CEUS) in the differential diagnosis of tuberculous and metastatic lymph nodes.

METHODS

Nineteen cervical tuberculous lymph nodes and 43 cervical metastatic lymph nodes were investigated. The CEUS perfusion patterns and parameters of time-intensity curve (TIC) were analyzed. Diagnostic accuracy and consistency of two physicians were compared before and after CEUS and TIC analysis.

RESULTS

Conventional ultrasonography showed no significant differences between tuberculous and metastatic lymph nodes. Concentric enhancement at the arterial phase of CEUS occurred in 15 of 19 (78.9%) tuberculous lymph nodes and 42 of 43 (97.7%) metastatic lymph nodes (P < .05). For the TIC curve, a steep descending curve with an apparent notch was commonly found in tuberculous lymph nodes (13 of 16). Although a shallow descending curve was common (40 of 43) in metastatic lymph nodes, most did not have a notch on the curve (39 of 43) (P < .01). The k-value and the peak intensity (PI) value of tuberculous lymph nodes were significantly higher and the △PI value was significantly lower than that of metastatic lymph nodes (P < .05, respectively). Kappa values for the diagnosis consistency of the two physicians before and after CEUS and TIC analysis were 0.582 and 0.761, respectively. Diagnostic accuracy before and after CEUS and TIC analysis was 47.4% (28 of 59) and 96.6% (57 of 59), respectively (P < .001).

CONCLUSIONS

Contrast-enhanced ultrasonography with TIC analysis is helpful in differentiating tuberculous from metastatic lymph nodes.

Value of contrast-enhanced ultrasound and PET/CT in assessment of extramedullary lymphoma

OBJECTIVE

The aim of the study was to evaluate clinical value of contrast-enhanced ultrasonography (CEUS) and PET/CT for assessment of extramedullary lymphoma, using histopathology as reference standard.

METHOD

A total of 63 patients with histopathologically-confirmed extramedullary lymphoma who had underwent CEUS and PET/CT examinations of suspicious lymph nodes included in the study. CEUS patterns and parameters (arrival time, peak time and intensity, base intensity, area under the time-intensity curve, ascending and descending slopes) and PET/CT parameters including maximum standardized uptake value, mean standardized uptake value, and metabolic tumor volume (MTV) were evaluated. Patients were classified into Hodgkin lymphomas (HL), non-Hodgkin lymphomas (NHL), early (stage I and II) and advanced (stage III and IV) lymphoma, B cells and T cells lymphoma, and aggressive and indolent lymphoma. The differences between the two independent samples were compared using non-parametric rank and inspection, P < 0.05 was considered statistically significant. The optimal cut-off value for parameters was used to predict the staging and pathology using Receiver Operating Characteristic (ROC) curve analysis.

RESULT

In the early and advanced group, the differences between △T and ascending slope (AS) were statistically significant (p = 0.010, 0.024 < 0.05). Hodgkin lymphomas (HL) or non-Hodgkin lymphomas (NHL) results were determined by optimal cut-off value of AT and TP (p = 0.001, 0.001 < 0.05). Aggressive or indolent lymphoma were determined by optimal cut-off values of Color Doppler flow resistance index (P = 0.001 < 0.05) and SUVmax (p = 0.001 < 0.05). There was no statistically significant difference between B and T cell lymphoma. And there was no statistically significant difference among the qualitative indexes. The optimal cutoff value for statistically significant indicators was calculated by ROC.

CONCLUSION

The quantitative parameters of CEUS and SUVmax of PET/CT are proven useful in assessment of different clinical and pathologic patterns of extramedullary lymphoma.

Evaluation of supplementary diagnostic value of contrast-enhanced ultrasound for lymph node puncture biopsy

Background

Contrast enhanced ultrasound (CEUS) is an effective way to evaluate the distribution of micro vessels in organs with little invasiveness. The qualitative evaluation and differential diagnosis of lymph node is essential for a number of clinical situations, including appropriate examination selection, oncologic staging, therapy and prognosis beyond diagnosis itself. The purpose of this study is to investigate the contribution of characterization of cervical lymphadenopathies on CEUS as an indication for lymph node puncture biopsy.

Methods

Records of 157 lymph nodes from 103 patients who had undergone CEUS examination were studied retrospectively, and enhancement patterns and characteristics were evaluated. The diagnoses obtained by means of core-needle biopsy examination or surgical removal, or patients were closely followed-up for at least 6 months. Of the lymph nodes examined, 94 were benign (48 lymphadenitis and 46 tuberculosis) and 63 were malignant (55 metastases and 8 lymphomas). The vascular characterization of lymph nodes was compared with results obtained by pathologic examination.

Results

The study using CEUS showed 55 (54.5%) cases of "peripheral" enhancement in group A and 47 (83.9%) cases of "hilar normal or activated" in group B. Inhomogeneous "spotted or cycle-like" enhancement in the equilibrium phase was seen in 80 (79.2%) cases of group A and only 11 (19.6%) cases of group B. The specificity, sensitivity and accuracy of CEUS examination result as an indication for puncture biopsy were 80.4%, 81.2% and 80.9%, respectively.

Conclusions

Centripetal perfusion in the early arterial phase or inhomogeneous spotted or cycle-like enhancement in the equilibrium phase of the cervical lymph nodes during CEUS can be used as an indication for core-needle biopsy with a high degree of accuracy. Conversely, for lymph nodes with more variable appearances, surgical removal or closely followed-up of nodes may be more appropriate.

Role of Contrast-Enhanced Ultrasound in the Pre-operative Diagnosis of Cervical Lymph Node Metastasis in Patients with Papillary Thyroid Carcinoma

The objective of this study was to prospectively evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in differentiating between benign and metastatic cervical lymph nodes in patients with papillary thyroid cancer (PTC). Three hundred nineteen cervical lymph nodes (162 metastatic from PTC and 157 benign) were evaluated using conventional ultrasonography (US) and CEUS before biopsy or surgery. Metastatic lymph nodes more often manifested centripetal or asynchronous perfusion, hyper-enhancement, heterogeneous enhancement, perfusion defects and ring-enhancing margins than benign lymph nodes at pre-operative CEUS (all p values < 0.001). The area under the receiver operating characteristic curve (AUC) for the combination of conventional US and CEUS (0.983, 95% confidence interval [CI]: 0.971-0.994) was higher than that of conventional US alone (0.929, 95% CI: 0.899-0.958) and CEUS (0.911, 95% CI: 0.876-0.947). In conclusion, CEUS is a promising tool in conjunction with conventional US for the pre-operative prediction of metastatic cervical lymph nodes in patients with PTC.

Monitoring of Blood Vessel Density Using Contrast-Enhanced High Frequency Ultrasound May Facilitate Early Diagnosis of Lymph Node Metastasis

Time-dependent alterations in the ultrasonography characteristics of lymph nodes during early-stage metastasis have not been compared with those of tumor-draining lymph nodes that do not develop tumor; this is partly due to the absence of an appropriate experimental model. In a previous study of lymph nodes with experimental early-stage metastasis, we used contrast-enhanced high-frequency ultrasound to demonstrate that an increase in lymph node blood vessel density preceded any changes in lymph node volume. In the present study, we used an experimental model of lymph node metastasis in which tumor cells metastasized from the subiliac lymph node to the proper axillary lymph node (the tumor-draining lymph node). We utilized contrast-enhanced high-frequency ultrasound to perform a longitudinal analysis of tumor-draining lymph nodes, comparing those at an early-stage of metastasis with those that did not develop detectable metastasis. We found that the normalized blood vessel density of an early-stage metastatic lymph node exhibited a progressive rise, whereas that of a tumor-draining lymph node not containing tumor began to increase later. For both types of lymph nodes, the normalized blood vessel density on the final day of experiments showed a trend towards being higher than that measured in controls. We further found that mice with an initially low value for lymph node blood vessel density subsequently showed a larger increase in the blood vessel density of the metastatic lymph node; this differed significantly from measurements in controls. The present study indicates that a longitudinal analysis of the blood vessel densities of tumor-draining lymph nodes, made using contrast-enhanced high-frequency ultrasound imaging, may be a potentially promising method for detecting early-stage lymph node metastasis in selected patients. Furthermore, our findings suggest that tumor in an upstream lymph node may induce alteration of the vascular structures in draining lymph nodes that do not contain tumor.

Role of contrast-enhanced endoscopic ultrasound in lymph nodes

Diagnosing unclear lymph node (LN) enlargements in the mediastinum and abdomen is the most important indication of endoscopic ultrasound (EUS)-fine needle aspiration (FNA) after the diagnosis and treatment of pancreatic diseases. Investigating LNs in these areas can happen in different clinical settings. Mostly, it is the first modality in general LN diseases without any peripheral LN enlargements. On the other hand, it can be the question of LN involvement in a known or suspected primary tumor. Due to EUS-FNA cytology, those questions can be answered highly, accurately. However, a primary discrimination of LNs might be helpful to increase the diagnostic value of the FNA cytology, especially in cases with multiple LN enlargements and hard to reach enlarged LNs for example by vessel interposition. Because of the unreliability of B-mode criteria, further diagnostic improvements such as elastography and contrast-enhanced EUS are investigated to increase the accuracy of the initial diagnosis.

Prognostic significance of number of nodes removed in patients with node-negative early cervical cancer

AIM

The aim of this study was to investigate whether the number of removed lymph nodes was associated with survival of patients with node-negative early cervical cancer and to analyze the prognostic significance of clinical and pathologic features in these patients.

METHODS

Patients with FIGO stage IA-IIB cervical cancer who underwent radical hysterectomy with lymphadenectomy without receiving preoperative therapy were reviewed retrospectively. Patients were all proved to have lymph-node-negative disease and classified into five groups based on the number of nodes removed. The Kaplan-Meier method and Cox's proportional hazards regression model were used in prognostic analysis.

RESULTS

The final dataset included 359 patients: 45 (12.5%) patients had ≤10 nodes removed, 93 (25.9%) had 11-15, 98 (27.3%) had 16-20, 64 (17.8%) had 21-25, and 59 (16.4%) had >25 nodes removed. There was no association between the number of nodes removed and survival of patients with node-negative early cervical cancer (χ²  = 6.19, P = 0.185). Similarly, subgroup analyses for FIGO stage IB1-IIB also showed that the number of lymph nodes was not significantly related to survival in each stage. Multivariate analyses showed that histology and depth of invasion were independent prognostic factors for survival in these patients.

CONCLUSION

If a standardized lymphadenectomy is performed, the number of lymph nodes removed is not an independent prognostic factor for patients with node-negative early cervical cancer. Our study suggests that there is inconclusive evidence to support survival benefit of complete lymphadenectomy among these patients.

Evaluation of Neck Lymph Node Metastasis on Contrast-Enhanced Ultrasound: An Animal Study

Objectives

To assess the performance of contrast-enhanced ultrasound (CEUS) intended to differentiate hyperplastic from malignant neck lymph nodes in an animal model.

Methods

Twenty-four New Zealand rabbits were randomly divided into two groups: neck lymph node metastasis group (12 rabbits) and reactive hyperplastic lymph node group (12 rabbits). Tongue VX2 carcinoma with cervical lymph node metastasis was induced in 12 rabbits by injecting VX2 carcinoma suspension into the left tongue submucosa. Hyperplastic neck lymph nodes were induced by injecting egg yolk in the submandibular region of the rabbits in hyperplastic group. CEUS were performed in both groups before and after intravenous administration of SonoVue. The site, number, echogenicity, longitudinal and transverse nodal dimensions, patterns of enhancement of the neck lymph nodes were observed and recorded.

Results

In both groups only one lymph node was found in the left (tumor) side of the neck. CEUS found 12 of 12 metastatic lymph nodes in metastasis group, and diagnosed 11 of 12 lymph nodes as metastatic. Histopathologic analysis revealed metastatic lesions in all 12 rabbits, each with one lymph node, and all 12 lymph nodes in hyperplastic group is inflammation lymph nodes. All 12 cases in the hyperplastic group showed centripetal homogeneous enhancement while in the metastasis group one case showed centripetal homogeneous enhancement, three cases showed centrifugal heterogeneous enhancement, and eight cases showed diffused heterogeneous enhancement. Only one lymph node was dissected on the left side of the neck in each rabbit in both groups.

Conclusion

CEUS can play a role in discriminating metastatic from hyperplastic lymph nodes in head and neck carcinoma.

Transcutaneous Ultrasound: Elastographic Lymph Node Evaluation. Current Clinical Applications and Literature Review

Distinguishing malignant versus benign lymphadenopathies is a major diagnostic dilemma in clinical medicine. Metastatic deposits in normal-sized lymph nodes (LNs) can be smaller than a millimeter, thus presenting a diagnostic challenge. In most clinical settings, however, enlarged LNs detected on imaging need to be classified as malignant or benign. Ultrasound seems to be a very reliable method for LN characterization because of the high resolution, especially in the subcutaneous areas. However, B-mode and Doppler-ultrasound criteria for characterization of a lymphadenopathy as benign or malignant are lacking specificity. Newer methods such as elastography seem to be valuable for identifying metastatic deposits within LNs and may help discriminate malignant and benign LNs. This review summarizes the different elastographic methods available and provides an overview of the relevant publications. According to the literature, elastography can be used for identifying metastatic deposits, to guide fine needle aspiration and to non-invasively choose the most suspicious LN of a group of enlarged LNs for targeted biopsy.

Five cases of axillary lymph node metastatic breast cancer on contrast-enhanced sonography

This study was performed to determine the importance of contrast-enhanced sonography for axillary lymph node metastatic breast cancer. Contrast-enhanced sonographic findings in 5 patients with breast cancer and axillary lymph node metastasis are discussed, and imaging-pathologic correlations are also presented in 3 cases. In all 5 cases, lymph nodes showed a perfusion defect in the late phase. Rapid arterial enhancement and wash-out were observed in 2 cases in which we performed second injections. Contrast-enhanced sonography may be effective for identifying metastatic lesions in lymph nodes, especially in the early stages.

Growing indications for CEUS: The kidney, testis, lymph nodes, thyroid, prostate, and small bowel

Contrast enhanced ultrasonography (CEUS) is increasingly used for non-hepatic applications as well, so that nearly all organs have been investigated. Among them, there is a growing clinical use for a variety of pathologies of the kidney, testis, and small bowel. The possibility to differentiate benign from malignant nodes in cancer patients has been investigated. A new application is in the detection of sentinel nodes after intradermal microbubble injection. The need to distinguish thyroid nodules eligible for fine needle aspiration cytology has led to the use of CEUS in thyroid examinations as well. The potential of CEUS for prostate cancer detection has been extensively investigated, with encouraging initial results. Early promise, however, has not been fulfilled. New perspective regards evaluation of the extent of prostate tissue devascularization following ablative treatments.

Value of contrast-enhanced ultrasonography in the differential diagnosis of enlarged lymph nodes: a meta-analysis of diagnostic accuracy studies

OBJECTIVE

To evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in differentiating between benign and malignant enlarged lymph nodes using meta-analysis.

MATERIALS AND METHODS

Pubmed, Embase, SCI and Cochrane databases were searched for studies (up to September 1, 2014) reporting the diagnostic performance of CEUS in discriminating between benign and malignant lymph nodes. Inclusion criteria were: prospective study; histopathology as the reference standard; and sufficient data to construct 2?2 contingency tables. Methodological quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Patient clinical characteristics, sensitivity and specificity were extracted. The summary receiver operating characteristic curve was used to examine the accuracy of CEUS. A meta-analysis was performed to evaluate the clinical utility in identification of benign and malignant lymph nodes. Sensitivity analysis was performed after omitting outliers identified in a bivariate boxplot and publication bias was assessed with Egger testing.

RESULTS

The pooled sensitivity, specificity and AUROC were 0.92 (95%CI, 0.85-0.96), 0.91 (95%CI, 0.82-0.95) and 0.97 (95%CI, 0.95-0.98), respectively. After omitting 3 outlier studies, heterogeneity decreased. Sensitivity analysis demonstrated no disproportionate influences of individual studies. Publication bias was not significant.

CONCLUSIONS

CEUS is a promising diagnostic modality in differentiating between benign and malignant lymph nodes and can potentially reduce unnecessary fine-needle aspiration biopsies of benign nodes.

Contrast-enhanced ultrasound (CEUS) facilitated US in detecting lateral neck lymph node metastasis of thyroid cancer patients: diagnosis value and enhancement patterns of malignant lymph nodes

OBJECTIVES

To examine the value of CEUS as a non-invasive tool in detecting lateral neck metastasis (LNM) and the enhancement patterns of malignant lymph nodes (LN) for thyroid cancer patients.

METHODS

Eighty-two consecutive patients, who underwent both preoperative non-enhanced US and CEUS examinations, were retrospectively reviewed. All patients underwent lateral neck dissection (LND). Enhancement patterns of 102 collected LNs matching to CEUS findings were analyzed.

RESULTS

CEUS detected LNM in 53 of 65 patients, showing a higher sensitivity and accuracy than that of conventional US (p = 0.109 and p = 0.154, respectively). Thirteen patients' surgical procedures were altered by CEUS findings, including nine true positive and four false positive cases. Five patients' surgical procedures were altered by conventional US findings, including two true positive and three false positive cases. Heterogeneous enhancement, perfusion defects, microcalcification, and centripetal/hybrid enhancement were all specific criteria for malignant LNs in univariate analysis. In multivariate analysis, only heterogeneous enhancement and centripetal/hybrid enhancement were significantly related to LN metastasis (p = 0.000 and p = 0.037, respectively).

CONCLUSIONS

CEUS may be a potential tool to facilitate conventional US in detecting LNM. Heterogeneous enhancement and centripetal/hybrid enhancement are useful criteria to distinguish between malignant and benign LNs.

KEY POINTS

• CEUS findings facilitated conventional US in detecting LNM. • Heterogeneous, centripetal/hybrid enhancement, microcalcification and perfusion defects were specific criteria of malignant LNs. • Heterogeneous and centripetal/hybrid enhancement were significantly related to LN metastasis in multivariate analysis.

Use of high frequency ultrasound to monitor cervical lymph node alterations in mice

Cervical lymph node evaluation by clinical ultrasound is a non-invasive procedure used in diagnosing nodal status, and when combined with fine-needle aspiration cytology (FNAC), provides an effective method to assess nodal pathologies. Development of high-frequency ultrasound (HF US) allows real-time monitoring of lymph node alterations in animal models. While HF US is frequently used in animal models of tumor biology, use of HF US for studying cervical lymph nodes alterations associated with murine models of head and neck cancer, or any other model of lymphadenopathy, is lacking. Here we utilize HF US to monitor cervical lymph nodes changes in mice following exposure to the oral cancer-inducing carcinogen 4-nitroquinoline-1-oxide (4-NQO) and in mice with systemic autoimmunity. 4-NQO induces tumors within the mouse oral cavity as early as 19 wks that recapitulate HNSCC. Monitoring of cervical (mandibular) lymph nodes by gray scale and power Doppler sonography revealed changes in lymph node size eight weeks after 4-NQO treatment, prior to tumor formation. 4-NQO causes changes in cervical node blood flow resulting from oral tumor progression. Histological evaluation indicated that the early 4-NQO induced changes in lymph node volume were due to specific hyperproliferation of T-cell enriched zones in the paracortex. We also show that HF US can be used to perform image-guided fine needle aspirate (FNA) biopsies on mice with enlarged mandibular lymph nodes due to genetic mutation of Fas ligand (Fasl). Collectively these studies indicate that HF US is an effective technique for the non-invasive study of cervical lymph node alterations in live mouse models of oral cancer and other mouse models containing cervical lymphadenopathy.

Can contrast-enhanced ultrasound distinguish malignant from reactive lymph nodes in patients with head and neck cancers?

The purpose of this study was to investigate the utility of contrast-enhanced ultrasound in differentiating benign from malignant cervical lymph nodes in patients with squamous cell carcinoma of the head and neck. A consecutive series of 17 patients with known head and neck malignancy scheduled for neck surgery and lymph node clearance were recruited for contrast-enhanced ultrasound evaluation. Sonographic signal intensity as a function of time, comparing features of time to peak, time to arrival and time to wash-out, was quantified. The selected node was removed surgically and submitted for histology. Contrast-enhanced ultrasound examination had 100% sensitivity and 85.7% specificity for lymph node involvement. Functional analysis revealed contrast peaks significantly earlier in the malignant nodes (mean ± standard deviation) of 24.14 ± 2.7 s compared with 29.33 ± 3.4 s (p = 0.0128). Contrast-enhanced ultrasound holds promise in the detection and characterization of metastatic nodes that would not be diagnosed as abnormal on the basis of conventional ultrasound criteria.