How Pre-operative Sentinel Lymph Node Contrast-Enhanced Ultrasound Helps Intra-operative Sentinel Lymph Node Biopsy in Breast Cancer: Initial Experience

Multimodal ultrasound imaging: a method to improve the accuracy of sentinel lymph node diagnosis in breast cancer

Aim

This study assessed the utility of multimodal ultrasound in enhancing the accuracy of breast cancer sentinel lymph node (SLN) assessment and compared it with single-modality ultrasound.

Methods

Preoperative examinations, including two-dimensional ultrasound (2D US), intradermal contrast-enhanced ultrasound (CEUS), intravenous CEUS, shear-wave elastography (SWE), and surface localization, were conducted on 86 SLNs from breast cancer patients. The diagnostic performance of single and multimodal approaches for detecting metastatic SLNs was compared to postoperative pathological results.

Results

Among the 86 SLNs, 29 were pathologically diagnosed as metastatic, and 57 as non-metastatic. Single-modality ultrasounds had AUC values of 0.826 (intradermal CEUS), 0.705 (intravenous CEUS), 0.678 (2D US), and 0.677 (SWE), respectively. Intradermal CEUS significantly outperformed the other methods (p<0.05), while the remaining three methods had no statistically significant differences (p>0.05). Multimodal ultrasound, combining intradermal CEUS, intravenous CEUS, 2D US, and SWE, achieved an AUC of 0.893, with 86.21% sensitivity and 84.21% specificity. The DeLong test confirmed that multimodal ultrasound was significantly better than the four single-modal ultrasound methods (p<0.05). Decision curve analysis and clinical impact curves demonstrated the superior performance of multimodal ultrasound in identifying high-risk SLN patients.

Conclusion

Multimodal ultrasound improves breast cancer SLN identification and diagnostic accuracy.

Association and predictive value of contrast‑enhanced ultrasound features with axillary lymph node metastasis in primary breast cancer

Primary breast cancer is the most common malignant tumor in women worldwide, and axillary lymph node metastasis (ALNM) is an important marker of disease progression in patients with breast cancer. The objective of the present study was to analyze the association between contrast-enhanced ultrasound (CEUS) features and ALNM in primary breast cancer and its predictive value. A total of 120 patients with breast cancer were assigned to the non-metastatic group (n=70) and metastatic group (n=50). The factors influencing ALNM were explored by multivariate logistic regression analysis. The consistency of CEUS, ordinary ultrasonography and pathological examination in the diagnosis of the ALNM of breast cancer was evaluated by consistency testing. The sensitivity, specificity and consistency rate of CEUS features and ordinary ultrasonography were analyzed by receiver operating characteristic curve and four-fold table analyses. High enhancement amplitude, centripetal enhancement sequence, increased maximum cortical thickness, high peak intensity and a larger area under the curve of lymph nodes were more commonly found in the metastatic group than in the non-metastatic group. The lymph node aspect ratio and time to peak were lower in the metastatic group than the non-metastatic group. The time to peak was a protective factor for ALNM in patients with breast cancer. The sensitivity, specificity and coincidence rate with pathological examination of CEUS in the diagnosis of ALNM were 92.00, 90.00 and 90.83%, while these of ordinary ultrasonography were 76.00, 80.00 and 78.33%, respectively. The consistency test indicated that CEUS and pathological examination were consistent in the diagnosis of ALNM in patients with breast cancer, with a κ value of 0.816, indicating a good consistency. The κ value of ordinary ultrasonography and pathological examination was 0.763, also indicating a good consistency. However, these results indicate that CEUS is more valuable than ordinary ultrasonography in the diagnosis of ALNM in cases of breast cancer. In conclusion, the present study indicates that CEUS features were influencing factors associated with ALNM in patients with breast cancer and may serve as an important reference for the preoperative prediction of ALNM in breast cancer.

The Value of Percutaneous Contrast-Enhanced Ultrasound in Sentinel Lymph Node Identification, Metastatic Status and Burden Diagnosis in Early Breast Cancer

OBJECTIVE

The aim of this study was to evaluate the value of percutaneous contrast-enhanced ultrasound (PCEUS) in the identification and characterization of sentinel lymph node (SLN).

METHODS

A total of 102 breast cancer patients were collected and underwent preoperative PCEUS, which was used to identify SLN and lymphatic drainage. SLNs were classified into 4 enhancement patterns, including 6 subtypes: homogeneous (I), featured inhomogeneous (II) including inhomogeneous hypoenhancement (IIa) and annular or semi-annular enhancement (IIb), focal filling defect (III) including filling defect area < 50% (IIIa) and filling defect area ≥ 50% (IIIb), and no enhancement (IV). The enhancement patterns of SLNs were compared with the final pathological diagnosis.

RESULTS

The identification rate of SLNs using PCEUS was 100% (102/102); the rate of identification of LCs was 100% (102/102), and the coincidence rate was 98.0% (100/102). Four lymphatic drainage patterns (LDPs) including 5 subtypes were found: single LC/single SLN(74.5%), multiple LCs/ single SLN (13.7%) including 2 subtypes:2 LCs/1 SLN and 3 LCs/1 SLN, single LC/multiple SLNs (7.8%), and multiple LCs/multiple SLNs (3.9%). A total of 86.3% (44/51) of patients without axillary metastasis could be safely selected for types I, IIa, and IIb, while the axillary metastasis rates of types III and IV were 74.4% and 87.5%, respectively (P < .001). Compared with grayscale US, the PCEUS significant improvement in diagnosing metastatic SLNs (.794 versus .579, P < .001). For the SLN metastatic burden, Types I, IIa, IIb, and IIIa had ≤2 SLNs metastases, with a pathological coincidence rate of (64/67, 95.5%), and types IIIb and IV had >2 SLNs metastases, with a pathological coincidence rate of (25/35, 71.4%) (P < .001). The AUC of PCEUS for the diagnosis of SLN metastatic status and burden was .794 and .879, respectively (P < .001).

CONCLUSION

PCEUS has a high identification rate for SLN and has good potential for diagnosing SLN metastatic status and burden by enhancement patterns.

Predictive value for axillary lymph node metastases in early breast cancer: Based on contrast-enhanced ultrasound characteristics of the primary lesion and sentinel lymph node

OBJECTIVE

To evaluate the value of contrast-enhanced ultrasound (CEUS) characteristics based on primary lesion combined with lymphatic contrast-enhanced ultrasound (LCEUS) patterns of SLN in predicting axillary lymph node metastasis (ALNM) with T1-2N0 breast cancer.

METHODS

A retrospective study was conducted in 118 patients with clinically confirmed T1-2N0 breast cancer. Conventional ultrasound (CUS) and CEUS characteristics of the primary lesion and enhancement patterns of SLN were recorded. The risk factors associated with ALNM were selected by univariate and binary logistic regression analysis, and the receiver operating characteristic (ROC) curve was drawn for the evaluation of predictive ALNM metastasis performance.

RESULTS

Univariate analysis showed that age, HER-2 status, tumor size, nutrient vessels, extended range of enhancement lesion, and the enhancement patterns of SLN were significant predictive features of ALNM. Further binary logistic regression analysis indicated that the extended range of enhancement lesion (p <  0.001) and the enhancement patterns of SLN (p <  0.001) were independent risk factors for ALNM. ROC analysis showed that the AUC of the combination of these two indicators for predicting ALNM was 0.931 (95% CI: 0.887-0.976, sensitivity: 75.0%, specificity: 99.8%).

CONCLUSION

The CEUS characteristics of primary lesion combined with enhancement patterns of SLN are highly valuable in predicting ALNM and can guide clinical axillary surgery decision-making in early breast cancer.

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.

A review of contrast-enhanced ultrasound using SonoVue® and Sonazoid™ in non-hepatic organs

Contrast-enhanced ultrasound (CEUS) is a dependable modality for the diagnosis of various clinical conditions. A judicious selection of ultrasound contrast agent (UCA) is imperative for optimizing imaging and improving diagnosis. Approved UCAs for imaging the majority of organs include SonoVue, a pure blood agent, and Sonazoid, which exhibits an additional Kupffer phase. Despite the fact that the two UCAs are increasingly being employed, there is a lack of comparative reviews between the two agents in different organs diseases. This review represents the first attempt to compare the two UCAs in non-hepatic organs, primarily including breast, thyroid, pancreas, and spleen diseases. Through comparative analysis, this review provides a comprehensive and objective evaluation of the performance characteristics of SonoVue and Sonazoid, with the aim of offering valuable guidance for the clinical application of CEUS. Overall, further clinical evidences are required to compare and contrast the dissimilarities between the two UCAs in non-hepatic organs, enabling clinicians to make an appropriate selection based on actual clinical applications.

Sentinel Lymph Node Identification in Post Neoadjuvant Chemotherapy Breast Cancer Patients Undergoing Surgical Excision Using Lymphosonography

OBJECTIVES

This study evaluated the efficacy of lymphosonography in the identification of sentinel lymph nodes (SLNs) in post neoadjuvant chemotherapy patients with breast cancer scheduled to undergo surgical excision.

METHODS

Seventy-nine subjects scheduled for breast cancer surgery with SLN excision completed this IRB-approved study, out of which 18 (23%) underwent neoadjuvant chemotherapy before surgery. Subjects underwent percutaneous Sonazoid (GE Healthcare) injections around the tumor area for a total of 1.0 mL. Lymphosonography was performed using CPS on an S3000 HELX scanner (Siemens Healthineers) with a linear probe. Subjects received blue dye and radioactive tracer as part of their standard of care. Excised SLNs were classified as positive or negative for the presence of blue dye, radioactive tracer and Sonazoid. The results were compared between methods and pathology findings.

RESULTS

Seventy-two SLNs were surgically excised from 18 subjects, 29 were positive for blue dye, 63 were positive for radioactive tracer and 57 were positive for Sonazoid. Comparison with blue dye showed that both radioactive tracer and lymphosonography achieved an accuracy of 53% (P > .50). Comparison with radioactive tracer showed that blue dye had an accuracy of 53%, while lymphosonography achieved an accuracy of 67% (P < .01). Of the 72 SLNs, 15 were determined malignant by pathology; the detection rate was 47% for blue dye (7/15), 67% for radioactive tracer (10/15) and 100% for lymphosonography (15/15) (P < .001).

CONCLUSIONS

Lymphosonography achieved similar accuracy as radioactive tracer and higher accuracy than blue dye for identifying SLNs. The 15 SLNs positive for malignancy were all identified by lymphosonography.

Contrast-enhanced ultrasound-guided sentinel lymph node biopsy in early-stage breast cancer: a prospective cohort study

OBJECTIVE

This study evaluated the identification efficiency of contrast-enhanced ultrasound (CEUS) for sentinel lymph nodes (SLN) to accurately represent the axillary node status in early-stage breast cancer.

METHOD

In total, 109 consecutive consenting patients with clinically node-negative and T1-2 breast cancer were included in this study. All patients received CEUS to identify SLN before surgery, and a guidewire was deployed to locate SLN in those who were successfully explored by CEUS. The patients underwent sentinel lymph node biopsy (SLNB), and the blue dye was used to trace SLN during the surgery. The decision to perform axillary lymph node dissection (ALND) depended on the intraoperative pathological identification of SLN by CEUS (CE-SLN). The concordance rate of pathological status between CE-SLN and dyed SLN was calculated.

RESULT

The CEUS detection rate was 96.3%; CE-SLN failed in 4 patients. Among the remaining 105 successful identifications, 18 were CE-SLN positive by intraoperative frozen section, and one with CE-SLN micrometastasis was diagnosed by paraffin section. No additional lymph node metastases were found in CE-SLN-negative patients. The concordance rate of pathological status between CE-SLN and dyed SLN was 100%.

CONCLUSION

CEUS can accurately represent the status of axillary lymph nodes in patients with clinically node-negative and small tumor burden breast cancer.

The Value of Contrast-Enhanced Ultrasound in the Detection of Sentinel Lymph Nodes in Malignant Melanoma

OBJECTIVE

To evaluate the location and characterization value of contrast-enhanced ultrasound (CEUS) in the detection of sentinel lymph nodes (SLNs) in malignant melanoma.

METHODS

SLNs and the lymph node network were tracked by subcutaneous injection of ultrasonic contrast agent around the tumor and preoperative localization, and qualitative analyses were performed. The SLNs were also detected by the intraoperative subcutaneous injection of carbon nanoparticles, and the findings were compared with lymph nodes located by CEUS. The accuracy of the preoperative lymph node identification was evaluated by the results of postoperative pathology, which served as the gold standard of detection.

RESULTS

In 47 patients with malignant melanoma, the mean number of SLNs detected by CEUS was 1.72 ± 0.10, while that by carbon nanoparticle administration it was 1.79 ± 1.07 (P = .371 > .05). Seven cases of lymph node metastasis were detected by CEUS, with a sensitivity of 70.0%, specificity of 97.3%, positive predictive value of 87.5%, negative predictive value of 92.3%, and accuracy of 91.5%. There was high consistency between the findings of CEUS and pathology in differentiating benign and malignant lymph nodes (kappa = 0.726, χ²  = 25.243, P < .001).

CONCLUSIONS

CEUS can localize and differentiate SLNs in malignant melanoma, and thus, may potentially guide clinical treatment in the future.

Contrast-enhanced lymphatic US can improve the preoperative diagnostic performance for sentinel lymph nodes in early breast cancer

OBJECTIVES

To evaluate the preoperative diagnostic value of contrast-enhanced lymphatic ultrasound (CEUS) for the sentinel lymph node (SLN) status in early breast cancer.

MATERIALS AND METHODS

We prospectively recruited 102 consecutive patients with clinically node-negative early breast cancer from July 2021 to October 2021. All patients underwent conventional US and percutaneous CEUS examinations. The CEUS of SLNs were classified into four enhancement patterns: homogeneous (I), featured inhomogeneous (II), focal defect (III), and no enhancement (IV). The diagnostic performance of conventional US and CEUS for SLN metastasis was assessed by receiver operating characteristic (ROC) curves and decision curves.

RESULTS

A total of 78 women were enrolled in this study, including 55, 18, and 5 patients with negative axilla, 1-2, and ≥ 3 metastastic SLNs pathologically, respectively. The identification rate of SLNs by CEUS was 100%. Patterns I and II can select 91.7% (44/48) of patients with disease-free axilla, while patterns III and IV had higher percentages of metastasis (65.2%, p < 0.001 and 57.1%, p < 0.002, respectively). For the SLN metastatic burden, 100% (48/48) of patients with pattern I/II had ≤ 2 metastatic SLNs. Compared with conventional US, the CEUS enhancement patterns showed significant improvement in diagnosing metastatic SLNs (0.813 vs 0.601, p < 0.001). CEUS had greater clinical benefits and correctly reclassified 48% of metastatic SLNs (p < 0.001) without sacrificing the classification accuracy of negative SLNs (p = 0.25), and could improve prediction accuracy by 0.42 (p < 0.001).

CONCLUSIONS

CEUS demonstrated better diagnostic performance and greater clinical benefits than conventional US for the preoperative diagnosis of SLNs, showing its potential to select candidates for precluding axillary surgery in early breast cancer.

KEY POINTS

• The homogeneous and featured inhomogeneous enhancement of SLNs are highly suggestive of negative LNs, while focal defect (p < 0.001) and no enhancement (p < 0.002) patterns had higher percentages of metastasis. • The proportion of SLNs with highly suspicious signs on conventional US increases as the type of enhancement pattern increases (no suspicious signs in pattern I/II, 34.8% in pattern III, and 85.7% in pattern IV). • Compared with conventional US, CEUS improved the area under the receiver operating characteristic curve (0.813 vs. 0.601, p < 0.001) and had greater clinical benefits (IDI = 0.42, p < 0.001) for the diagnosis of axillary metastasis.

Study on Sentinel Lymph Node and Its Lymphatic Drainage Pattern of Breast Cancer by Contrast-Enhanced Ultrasound

OBJECTIVES

Sentinel lymph node (SLN) and its lymphatic drainage pattern (LDP) of breast cancer were studied by contrast-enhanced ultrasound (CEUS).

METHODS

From July 2017 to December 2019, patients with SLN localization of breast cancer in Sichuan Academy of Medical Sciences·Sichuan Provincial People's Hospital were selected. The sentinel lymph system of breast cancer was observed by CEUS before both operation and blue staining in the surgery. The location, number, and route of sentinel lymphatic channel (SLC) were recorded, along with the number, size, and the depth from skin of SLN. LDPs were summarized according to these basic characteristics of SLC and SLN.

RESULTS

A total of 368 cases were included; 465 SLCs and 423 SLNs were detected. Most of the SLCs were originated from the outer upper quadrant of areola. Eleven LDPs were found, including 31 subtypes of LDPs. There were 6 cases of type A (1.63%), 15 cases of type B (4.08%), 223 cases of type C (57.88%), 38 cases of type D (10.33%), 2 cases of type E (0.54%), 3 cases of type F (0.82%), 50 cases of type G (13.59%), 30 cases of type H (8.15%), 2 cases of type I (0.54%), 6 cases of type J (1.63%), and 3 cases of type K (0.82%).

CONCLUSIONS

The most common LDP of breast cancer was one SLC originated from the upper quadrant of areola with one SLN. CEUS can identify the LDP before surgery to reduce the false negative rate of SLN biopsy.

Diagnostic Significance of 3D Automated Breast Volume Scanner in a Combination with Contrast-Enhanced Ultrasound for Breast Cancer

The incidence of cancer is increasing today, particularly lung and chest cancer. Employing novel methods to detect cancer in its earliest stages and discover painless, noninvasive treatments are urgently needed. The goal of the proposed study is to investigate the value of automated breast volume scanning (ABUS) in conjunction with contrast-enhanced ultrasonography (CEUS) in properly diagnosing breast cancer in its early stages and the effectiveness of neoadjuvant chemotherapy (NAC) in treating the disease. For the research study, information on 98 patients who had NAC and surgery in the breast surgery department of the Shaanxi Provincial Cancer Hospital has been gathered. All patients have received four cycles of NAC and underwent conventional ultrasound (HUSS), CEUS, ABUS, and pathological examination. At the same time, receiver operating characteristic (ROC) curve analysis, single factor, multiple linear regression, and other methods have also been used to analyze the diagnostic efficacy of breast cancer and NAC efficacy evaluation results. The study of this paper is totally based on the data collected from Shaanxi Provincial Cancer Hospital. The statistical and computational analyses are performed on the data collected for drawing inferences. When the findings are compared to the results of the pathological examination, HUSS has demonstrated a significant distinction between benign and malignant diagnoses with a statistical value of P < 0.05.ABUS combined with CEUS has shown no considerable differences in correlation study. Except for negative likelihood ratio, the diagnostic performance indexes of CEUS+ ABUS are substantially higher than HHUS with P < 0.05. ROC curve analysis is also performed which shows that CEUS and ABUS combination has higher precision in the analysis of breast cancer. ABUS pooled with CEUS shows great application value in the judgment of breast cancer as per the results obtained from the statistical analysis on data of 98 patients.

The value of preoperative sentinel lymph node contrast-enhanced ultrasound for breast cancer: a large, multicenter trial

Objective

The study conducted a multicenter study in China to explore the learning curve of contrast enhanced ultrasound (CEUS) for sentinel lymph nodes (SLNs), the feasibility of using this technique for the localization of SLNs and lymphatic channels (LCs) and its diagnostic performance for lymph node metastasis.

Method

Nine hundred two patients with early invasive breast cancer from six tertiary class hospitals in China were enrolled between December 2016 and December 2019. Each patient received general ultrasound scanning and SLN-CEUS before surgery. The locations and sizes of LCs and SLNs were marked on the body surface based on observations from SLN-CEUS. These body surface markers were then compared with intraoperative blue staining in terms of their locations. The first 40 patients from each center were included in determining the learning curve of SLN-CEUS across sites. The remaining patients were used to investigate the diagnostic efficacy of this technique in comparison with intraoperative blue staining and pathology respectively.

Result

The ultrasound doctor can master SLN-CEUS after 25 cases, and the mean operating time is 22.5 min. The sensitivity, specificity, negative predictive value, and positive predictive value of SLN-CEUS in diagnosing lymph node metastases were 86.47, 89.81, 74.90, and 94.97% respectively.

Conclusion

Ultrasound doctors can master SLN-CEUS with a suitable learning curve. SLN-CEUS is a feasible and useful approach to locate SLNs and LCs before surgery and it is helpful for diagnosing LN metastases.

Lymphatic Mapping Using US Microbubbles before Lymphaticovenous Anastomosis Surgery for Lymphedema

Background Lymphaticovenous anastomosis (LVA) surgery is an effective surgical treatment of secondary lymphedema in the extremities, but indocyanine green (ICG) fluorescent lymphography, the reference standard for imaging target lymphatic vessels, has several limitations. More effective methods are needed for preoperative planning. Purpose To evaluate whether contrast-enhanced US (CEUS) can be used to identify target lymphatic vessels for LVA surgery in patients with secondary upper extremity lymphedema and compare the results with those from ICG fluorescent lymphography. Materials and Methods In this single-center retrospective review, CEUS with intradermal injection of microbubbles was performed in patients before LVA surgery in the upper extremities between October 2019 and September 2021. All patients had secondary upper extremity lymphedema from breast cancer treatment. Technical success rate was defined as lymphatic vessels identified with use of CEUS that led to successful LVAs. Descriptive statistics were used. Results All 11 patients were women (mean age, 56 years ± 8 [SD]). The median number of microbubble injection sites was 11 (range, 8-14). CEUS helped identify lymphatic vessels in all 11 women, including in six women in whom ICG fluorescent lymphography could not be performed or failed to help identify any targets. Thirty-five explorations (median, three per patient; range, two to four) were performed, and 24 LVAs (median, three per patient; range, zero to four) were created. Of the anastomoses, 33% (eight of 24) were mapped with use of both CEUS and ICG fluorescent lymphography, 58% (14 of 24) with CEUS only, and 8% (two of 24) with ICG fluorescent lymphography only. Among the 33 explorations on targets mapped with CEUS, an anastomosis could be made at 22 sites, for a technical success rate of 67%. Seven women had at least one additional LVA created from the use of CEUS. Conclusion Contrast-enhanced US is a promising tool for identifying lymphatic vessels in the upper extremities, especially when indocyanine green fluorescent lymphography fails to depict targets or cannot be used. Published under a CC BY 4.0 license.

Advanced diagnostic imaging of sentinel lymph node in early stage breast cancer

Sentinel lymph node biopsy has been regarded as the standard procedure for early staging breast cancer. One of the key steps is to locate the sentinel lymph node (SLN). The recommended method is the joint use of blue dye and radioisotope. However, due to radionuclide radiation and high cost, it is urgent to develop more convenient and sensitive imaging methods to accurately locate SLN. This article discusses the advancement of accurately locating SLN by isotope tracer imaging, magnetic tracer method, computed tomographic lymphography, and trans-lymphatic contrast-enhanced ultrasound, as well as proposing new propose for clinical diagnosis.

The value of contrast-enhanced ultrasound enhancement patterns for the diagnosis of sentinel lymph node status in breast cancer: systematic review and meta-analysis

BACKGROUND

The sentinel lymph node (SLN) can represent the metastasis status of axillary lymph nodes and is a prognostic factor of breast cancer. Preoperative imaging provides information for axillary surgery decision-making, and this meta-analysis evaluated the diagnostic value of contrast-enhanced ultrasound (CEUS) for SLN status in breast cancer patients.

METHODS

The PubMed, Embase, Medline, Google Scholar, Clinical Trails gov. and Cochrane Library databases were searched from inception until 31 March 2020. Two review authors independently screened and selected the relevant studies and extracted data, and the assessment of the methodological quality of studies was according to the QUADAS-2 tool. The diagnostic value of CEUS was assessed by calculating the pooled sensitivity, specificity, area under the curve, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio, and a summary receiver operating characteristic curve and hierarchical modeling method was used to conduct the meta-analysis.

RESULTS

Five studies with 771 breast cancer patients were included, and the results showed CEUS could provide additional information for SLN preoperative diagnosis. A homogeneous or uniform enhancement pattern suggested a benign lymph node, and a heterogeneous, no pattern, or weak enhancement pattern suggested a node was malignant, demonstrating high sensitivity of 0.960 (95% CI: 0.856, 0.989) and moderate specificity of 0.807 (0.581, 0.926). The pooled positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 4.987 (2.104, 11.822) and 0.049 (0.014, 0.168), and 101.294 (31.202, 328.837), respectively.

CONCLUSIONS

A homogeneous enhancement pattern was highly suggestive of benign lymph nodes with high sensitivity. CEUS could effectively identify the SLN, and facilitate the diagnosis of its metastatic status.

REGISTRATION NUMBER

PROSPERO protocol CRD42020176828.

Preoperative localization of sentinel lymph nodes using percutaneous contrast-enhanced ultrasonography in patients with breast cancer

BACKGROUND

This study aimed to investigate the feasibility of preoperative identification of sentinel lymph nodes (SLNs) by contrast-enhanced ultrasound (CEUS) for patients with breast cancer.

METHODS

The patients with T1-T2N0M0 breast cancer who were scheduled for primary surgical treatment were recruited. All the patients had received a periareolar intradermal injection of an ultrasonic contrast agent (SonoVue, Bracco, Milan, Italy) followed by an ultrasound to identify contrast-enhanced SLNs. A guidewire was deployed to localize the SLN. Methylene blue stain was used to help trace SLNs during the operation. The identification rate and accuracy rate were recorded. The number of SLNs labeled by two methods was counted and compared using Wilcoxon testing.

RESULTS

A total of 366 SLNs were detected in 72 patients by methylene blue intraoperatively, with a median of 5 lymph nodes [interquartile range (IQR), 4-6] per patient. A total of 95 SLNs were detected in 63 patients (87.5%) by CEUS, with a median of 1 lymph node (IQR, 1-2) per patient. The number of SLNs detected by CEUS was significantly less than that labeled by the methylene blue staining method (Z=-7.362, P=0000). Pathology confirmed 12 single metastases in all the lymph nodes examined, 10 of which were the only lymph node identified by CEUS.

CONCLUSIONS

Periareolar intradermal injection of an ultrasonic contrast agent was an effective and convenient supplementary to localize SLNs. The technique was expected to improve the accuracy of axillary staging with minor surgical trauma and postoperative complications.

Comparison of lymphatic contrast-enhanced ultrasound and intravenous contrast-enhanced ultrasound in the preoperative diagnosis of axillary sentinel lymph node metastasis in patients with breast cancer

OBJECTIVES

This study aimed to compare diagnostic efficiency for axillary sentinel lymph node (SLN) metastasis between lymphatic contrast-enhanced ultrasound (LCEUS) and intravenous contrast-enhanced ultrasound (ICEUS) in patients with breast cancer. We also examined whether adding ICEUS to LCEUS could improve the diagnostic accuracy of LCEUS.

METHODS

Sixty-nine patients with breast cancer were recruited preoperatively. All patients underwent LCEUS followed by ICEUS, and the enhancement pattern of one SLN was analysed for each patient. The targeted SLN was marked with wire and excised during surgery. The imaging diagnosis was compared with the histopathological result. Diagnostic efficiency was compared among LCEUS, ICEUS, and the combination of LCEUS and ICEUS.

RESULTS

The sensitivity values for LCEUS, ICEUS, and the combination of LCEUS and ICEUS were 86.2%, 82.6% and 93.1%, respectively. Specificity values for the three methods were 95.0%, 92.5% and 87.5%, respectively. Accuracy values for the three methods were 91.3%, 88.4% and 89.9%, respectively. The area under the receiver operating characteristic (ROC) curve for LCEUS was 0.906, and there was no significant difference among LCEUS, ICEUS, and the combination of LCEUS and ICEUS (p = 0.752).

CONCLUSIONS

LCEUS may represent an accurate method for predicting SLN metastasis preoperatively. Our findings suggest that adding ICEUS to LCEUS for SLN evaluation in patients with breast cancer is unnecessary.

ADVANCES IN KNOWLEDGE

This is the first study in which both LCEUS and ICEUS were performed for the same lymph node and the first to compare the diagnostic efficiency of LCEUS, ICEUS, and the combination of LCEUS + ICEUS.

Sentinel lymph node detection by combining nonradioactive techniques with contrast agents: State of the art and prospects

The status of sentinel lymph nodes (SLNs) has a substantial prognostic value because these nodes are the first place where cancer cells accumulate along their spreading route. Routine SLN biopsy ("gold standard") involves peritumoral injections of radiopharmaceuticals, such as technetium-99m, which has obvious disadvantages. This review examines the methods used as "gold standard" analogs to diagnose SLNs. Nonradioactive preoperative and intraoperative methods of SLN detection are analyzed. Promising photonic tools for SLNs detection are reviewed, including NIR-I/NIR-II fluorescence imaging, photoswitching dyes for SLN detection, in vivo photoacoustic detection, imaging and biopsy of SLNs. Also are discussed methods of SLN detection by magnetic resonance imaging, ultrasonic imaging systems including as combined with photoacoustic imaging, and methods based on the magnetometer-aided detection of superparamagnetic nanoparticles. The advantages and disadvantages of nonradioactive SLN-detection methods are shown. The review concludes with prospects for the use of conservative diagnostic methods in combination with photonic tools.

Feasibility and efficiency of contrast enhanced ultrasound real time guided fine needle aspiration for sentinel lymph node of breast cancer

AIM

To assess the feasibility and efficiency of contrast-enhanced ultrasound (CEUS) real-time guided fine needle aspiration (FNA) for sentinel lymph node (SLN) of breast cancer.

MATERIALS AND METHODS

This retrospective study reviewed 21 breast cancer patients who scheduled for surgical resection performed CEUS real-time guided SLN-FNA and intraoperative SLN biopsy (SLNB). The success rate of CEUS real-time guided SLN-FNA was analyzed. The FNA diagnostic efficiency of SLN metastasis was analyzed compared to SLNB.

RESULTS

Twenty-six SLNs were detected by intradermal CEUS whereas 130 SLNs were detected by SLNB. The median SLNs detected by intradermal CEUS (n = 1) and by SLNB (n = 5) was significantly difference (p < 0.001). All 26 CE-SLNs of 21 patients were successfully performed intradermal CEUS dual image real-time guided SLN-FNA including 5 SLNs of 4 patients which were difficult to distinguish in conventional ultrasound. Compared to SLNB, FNA found 2 of 5 cases of SLN metastasis, the diagnosis sensitivity, specificity, positive predictive value, negative predictive value, false negative rate, false positive rate and Yoden index were 40%, 100%, 100%, 84.2%, 60%, 0%and 40%, respectively.

CONCLUSION

SLN-FNA real-time guided by dual CEUS image mode was technically feasible. Patients with a positive SLN-FNA should be advised to ALND without intraoperative SLNB according to Chinese surgeon and patients' conservatism attitude. But a negative SLN-FNA did not obviate the need of conventional SLNB because of the high false negative rate.

Contrast-Enhanced Ultrasound for Precise Sentinel Lymph Node Biopsy in Women with Early Breast Cancer: A Preliminary Study

BACKGROUND

Sentinel lymph node biopsy (SLNB), as a common method for axillary staging of early breast cancer, has gradually attracted people's attention to the false-negative rate and postoperative complications. The aim of the study is to investigate the clinical value of preoperative contrast-enhanced ultrasound (CEUS) for intraoperative SLNB in early breast cancer patients.

METHODS

A total of 201 patients scheduled for SLNB from September 2018 to April 2021 were collected consecutively. Preoperative CEUS was used to identify sentinel lymph nodes (SLN) and lymphatic drainage in breast cancer patients.

RESULTS

The SLN identification rate of CEUS was 93.0% (187/201) and four lymphatic drainage patterns were found: single LC to single SLN (70.0%), multiple LCs to single SLN (8.0%), single LC to multiple SLNs (10.2%), and multiple LCs to multiple SLNs (11.8%). The Sen, Spe, PPV, NPV, AUC of CEUS, US and CEUS + US in diagnosis of SLNs were 82.7%, 80.4%, 73.8%, 87.4%, 0.815; 70.7%, 77.7%, 68.0%, 79.8%, 0.742; and 86.7%, 77.7%, 72.2%, 89.7%, 0.822, respectively. There was no statistically significant difference between the diagnostic performance of CEUS and CEUS + US (p = 0.630).

CONCLUSIONS

CEUS can be used to preoperatively assess the lymphatic drainage patterns and the status of the SLNs in early breast cancer to assist precision intraoperative SLNB.

Diagnostic efficacy of sentinel lymph node in breast cancer under percutaneous contrast-enhanced ultrasound: An updated meta-analysis

Background

To investigate the diagnostic efficacy of sentinel lymph nodes (SLN) in breast cancer by percutaneous contrast‐enhanced ultrasound (CEUS) through pooled analysis of relevant studies published before June 2021.

Methods

We conducted a systematic review and meta‐analysis of relevant studies by searching the electronic databases of PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, Wanfang and VIP and the studies were screened according to their inclusion and exclusion criteria. Sensitivity (SEN), specificity (SPE), positive likelihood ratio (+LR), negative likelihood ratio (−LR) and diagnostic odds ratio (DOR) were calculated by Meta‐disc 1.4 software and the summary receiver operating characteristic (SROC) curve and area under the curve of ROC (AUC) were constructed.

Results

Twenty‐two publications evaluating the diagnostic efficacy of SLN in breast cancer under percutaneous CEUS were included in the meta‐analysis. The diagnostic sensitivity, specificity were 0.86 (95% CI: 0.83–0.88) and 0.89 (95% CI: 0.87–0.91) for SLN in breast cancer detected by percutaneous CEUS respectively using a random effect model. The +LR and –LR were combined in a random effect model due to significant statistical heterogeneity (p < 0.05). The pooled +LR, −LR were 7.06 (95% CI: 4.34–11.50), and 0.17 (95% CI: 0.12–0.24), respectively. The combined DOR was 53.32 (95% CI: 29.74–95.61) for SLN diagnosis in breast cancer by percutaneous CEUS under a random effect model. The AUC was 0.94 which indicated that CEUS had high diagnostic efficacy of SLN in patients with breast cancer.

Conclusions

CEUS is a noninvasive method for the detection SLN in patients of breast cancer with relative high prediction efficacy.

Contrast-Enhanced Ultrasound in Locating Axillary Sentinel Lymph Nodes in Patients with Breast Cancer: A Prospective Study

The objective was to explore the clinical value of contrast-enhanced ultrasound (CEUS) in locating the sentinel lymph node (SLN) in patients with early breast cancer. We screened 143 consecutive patients with breast cancer between July 2017 and August 2019. The number of SLNs identified by CEUS and dual labeling (blue dye and radiolabeled colloid) were recorded. The accuracy of CEUS plus fine-needle aspiration cytology (FNAC) was assessed. The rate of identification of SLNs with CEUS was 84.0% (121/144), and that of dual labeling was 97.92% (141/144). There was no significant association between non-enhancement (p = 0.060) or inhomogeneous enhancement (p = 0.468) and lymph node metastasis. The sensitivity and specificity of CEUS-SLNs plus FNAC was 78.38% and 100%, respectively. The technique of CEUS is a promising method for locating the axillary SLN. But it is hard to identify lymph node metastasis with CEUS alone. CEUS-SLNs plus FNAC is a sound technique for diagnosis of the metastasis of SLN.

Preoperative evaluation and influencing factors of sentinel lymph node detection for early breast cancer with contrast-enhanced ultrasonography: What matters

Sentinel lymph node (SLN) is important in the early diagnosis of breast cancer. We aimed to evaluate the role of contrast-enhanced ultrasonography (CEUS) in the preoperative evaluation for SLN and potentially influencing factors, to provide evidence to the management of breast cancer.Patients with breast cancer who treated in our hospital from May 2018 to May 2020 were selected. All patients underwent CEUS examination to find SLN and judged whether the lymph node had cancer metastasis. We evaluated the sensitivity, specificity, and accuracy of CEUS in predicting SLN, and its differences in pathological diagnosis results and related influencing factors were also analyzed.A total of 108 patients with breast cancer were included. And a total of 248 SLNs were detected. The sensitivity of CEUS to the preoperative evaluation of SLN was 84.67%, the specificity was 81.14%, the positive predictive value was 76.08%, and the negative predictive value was 89.27%, the positive likelihood ratio was 4.06, and the negative likelihood ratio was 0.14. The area under the curve of the preoperative evaluation of SLN in CEUS examination was 0.813 (95% confidence interval: 0.765-0.911), and there was significant difference in the size of SLNs between SLN-negative and SLN-positive groups (P = .043).Preoperative CEUS has good predictive value for the SLN detection in patients with breast cancer, and it is worthy of clinical application.

The value of contrast-enhanced ultrasound in determining the location of sentinel lymph nodes in breast cancer

Background

This study aimed to explore the sentinel lymph node (SLN) identification rate in breast cancer by subcutaneous and intradermal injection of ultrasound contrast agent in the mammary areola region, compared to the results achieved with methylene blue (MB).

Methods

A total of 390 breast cancer patients with planned sentinel lymph node biopsy from our breast surgery department from July 2017 to February 2019 were enrolled. All patients were subjected to preoperative contrast-enhanced ultrasound (CEUS), that involved an intracutaneous injection of 1 mL ultrasonic contrast agent (UCA) at 3 and 6 o ‘clock, as well as a subcutaneous injection of 1 mL UCA at 9 and 12 o’clock. The enhanced lymph nodes along the enhanced lymphatic vessels from the mammary areola were traced. The number of enhanced lymph nodes were recorded, and an ultrasound-guided injection of 1:10 diluted carbon nanoparticles were used to mark all first site enhanced lymph nodes (i.e., SLNs). An intraoperative dye method (MB) was used to track the SLNs and the results were compared with the CEUS findings.

Results

Among the 390 cases of breast cancer, enhanced SLNs were observed in 373 patients after an injection of UCA with an identification rate of 95.64 % (373/390), compared to the identification rate of 92.05 % (359/390) using the intraoperative MB. The difference between the two methods was statistically significant (P = 0.016). And among the 390 patients, a total of 808 enhanced lymph nodes were traced by preoperative CEUS, with a median of 2 (1,3). A total of 971 blue-stained lymph nodes were traced using the intraoperative MB, with a median of 2 (2,3), indicating a statistically significant difference (p < 0.001).

Conclusions

Intradermal and subcutaneous injections of UCA in the mammary areola region may have clinical application value for the identification and localization of SLNs in breast cancer patients. The identification rate is higher than that of blue dye method, which can be used as a new tracer of sentinel lymph node biopsy and complement other staining methods to improve the success rate.

Comparative study on the diagnostic value of intravenous/peritumoral injection of indocyanine green for metastatic lymph node location in patients with head and neck squamous cell carcinoma (HNSCC)

Background

Accurate assessment of regional lymph node (LN) status is essential for the treatment of head and neck squamous cell carcinoma (HNSCC) patients. In this study, we aimed to compare the difference between intravenous injection of indocyanine green (ICG) and peritumoral injection of ICG in the location of metastatic LNs.

Methods

Twenty-nine patients were enrolled in this study with 13 patients receiving intravenous injection of ICG and 16 patients receiving peritumoral injection of ICG. During the surgery, the fluorescence-positive LNs in vivo were sent to undergo frozen section after fluorescence intensity was recorded. After the cervical LN dissection, all LNs were sorted by region, and the fluorescence intensity was recorded before the LNs were sent for paraffin section.

Results

During the surgery, both intravenous or peritumoral injections with near-infrared (NIR) fluorescence imaging of ICG had their respective pros and cons in vivo, with the sensitivity and specificity being 62.5%/75% and 98.1%/89.1% respectively. After the surgery, both methods could reduce the pathological workload by preselecting the LNs at-risk in the premise of accurate assessing the cervical LN stage. However, intravenous ICG administration was more valuable in determining all types of LN status according to the fluorescence intensity [area under the curve (AUC): 0.91 vs. 0.78, P<0.001].

Conclusions

With the assistance of NIR fluorescence imaging using ICG, both administration methods could reduce the postoperative complication and the pathological workload, whereas the intravenous mode of ICG administration is superior in application value.

Percutaneous Sonazoid-enhanced ultrasonography combined with in vitro verification for detection and characterization of sentinel lymph nodes in early breast cancer

Objectives

To assess the efficacy of percutaneous Sonazoid-enhanced ultrasound and in vitro verification for identification sentinel lymph nodes (SLNs) and diagnosis of metastatic SLNs in patients with early breast cancer (BC).

Methods

Sixty-eight patients with early BC were enrolled finally. After the induction of general anesthesia, 0.4 ml of Sonazoid (SNZ), a new second-generation tissue-specific ultrasound contrast agent (UCA), mixed with 0.6 ml of methylene blue, was injected intradermally. The lymphatic vessels and connected SLNs were immediately observed and marked. After being resected, these SLNs were soaked in saline water and examined still in the mode of contrast-enhanced ultrasound (CEUS) in vitro. This procedure could ensure that all the enhanced nodes had been removed as much as possible. The numbers of SLNs detected by UCA and blue dye were recorded. The enhancement patterns of SLNs were compared with the final pathological results.

Results

SLNs detection rate by SNZ-CEUS was 100%, which was higher than that by blue dye (95.59%). CEUS identified a median of 1.5 nodes, while blue dye identified a median of 1.9 nodes per case (p = 0.0012). When homogeneous high perfusion and complete annular high perfusion were regarded as negative nodes, the sensitivity and negative predictive value were 92.31% and 96.79% respectively, while the specificity was 84.21%.

Conclusions

Percutaneous SNZ-enhanced ultrasonography combined with in vitro verification is a feasible and reliable method for SLNs identification intraoperatively. Enhancement patterns can be helpful in determining the status of SLNs.

Key Points

• CEUS with percutaneous injection of Sonazoid can successfully identify SLNs with the rate of 100% in early breast cancer patients, higher than 95.59% of blue dye.

• Sonazoid, with high affinity with reticuloendothelial cells, increases the imaging time of SLNs and facilitates biopsy intraoperatively better than Sonovue as a lymphatic tracer.

• Homogenous high and complete annular high perfusions have a sensitivity of 92.31% and a negative predictive value of 96.79% in the prediction of uninvolved SLNs.

Contrast-enhanced ultrasound for sentinel lymph node mapping in the routine staging of canine mast cell tumours: A feasibility study

Canine mast cell tumours (MCTs) typically spread to lymph nodes (LNs) before reaching distant sites, and LN assessment is an important part of MCT staging. Sentinel LN (SLN) mapping techniques to identify draining LNs are being developed and could improve the accuracy of MCT staging. The primary objective of this feasibility study was to determine the safety and effectiveness of contrast-enhanced ultrasound (CEUS) to identify SLNs. Secondary objectives were to determine if the SLNs identified by CEUS coincided with the regional LN predicted by the anatomical lymphosomes, if previous MCT excision altered CEUS SLN findings, and if CEUS could identify MCT nodal metastases. Between June 2017 and March 2019, 59 dogs with 62 MCTs were enrolled. No adverse events related to CEUS were reported. CEUS detected at least 1 SLN in 59/62 MCTs (95.2%, 95% CI: 86.5-99.0%). In only 32/59 (54.2%) MCTs, clinicians would have correctly predicted the SLN(s) identified by CEUS. Among the 35 MCTs that had histological examination of the SLN(s), the prevalence of metastasis was 60% (95% CI: 42.1-76.1%). Additional staging procedures did not reveal any metastases in dogs with histologically non-metastatic SLNs. Integration of CEUS SLN mapping into the routine staging of MCTs is promising, but future studies are required to refine this procedure and to investigate if it would translate into a clinical benefit.

Accuracy of CEUS-guided sentinel lymph node biopsy in early-stage breast cancer: a study review and meta-analysis

Objective

To investigate whether preoperative localization of sentinel lymph node (SLN) by contrast-enhanced ultrasound (CEUS) can further improve the accuracy of sentinel lymph node biopsy (SLNB).

Method

Collect published literatures or conference reports by searching electronic databases. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) evaluation method is used to evaluate the quality of the screened literatures. The pooled risk ratio of cancer metastasis of SLN identified by CEUS (CE-SLN) compared with SLN not identified by CEUS (nonCE-SLN) is calculated, and the pooled diagnostic accuracy of CE-SLN for pathological status of all SLNs is also evaluated.

Result

Through search and screening, a total of 16 studies were included, of which five and seven studies, respectively, entered the meta-analysis of metastatic risk ratio and diagnostic accuracy. The localization rate of preoperative CEUS for sentinel lymph nodes was 70 to 100%. The meta-analysis shows that the risk of metastasis of SLN identified by CEUS is significantly higher than that not identified by CEUS, 26.0% vs 4.6%, and risk ratio (RR) is 6.08 (95% CI 4.17–8.85). In early-stage breast cancer, the pathological status of CE-SLN is a good representative of all SLNs, with a pooled sensitivity of 98% (95% CI 0.94–1.00), pooled specificity of 100% (95% CI 0.99–1.00), diagnostic odds ratio (DOR) of 2153.18 (95% CI 476.53–9729.06), and area under the subject receiver operating characteristic (SROC) curve of 0.9968.

Conclusion

In early-stage breast cancer, preoperative localization of SLN by CEUS is expected to further improve the accuracy of sentinel lymph node biopsy (SLNB).

Subcapsular Injection of Ultrasonic Contrast Agent Distinguishes between Benign and Malignant Lymph Node Lesions Exhibiting Homogeneous Enhancement in Intravenous Contrast-Enhanced Ultrasound Images

We aimed to evaluate whether subcapsular injection of ultrasonic contrast agent (UCA) can distinguish between benign and malignant lymph node (LN) lesions exhibiting homogeneous enhancement in intravenous contrast-enhanced ultrasound (CEUS) images. From November 2012 to July 2015, 32 patients with superficial lymphadenopathy exhibiting homogeneous enhancement after intravenous CEUS were enrolled. A small amount of UCA was injected into LNs using a subcapsular approach, and perfusion characteristics were recorded. Using the pathology identified via core needle biopsy as the gold standard, we calculated the sensitivity, specificity and accuracy of the technique in terms of distinguishing between benign and malignant LN lesions. Pathology revealed 23 cases of true benign and 9 cases of true malignant LN lesions; the former included 2 cases of tuberculosis and 21 cases of reactive hyperplasia, and the latter included 7 lymphomas and 2 metastases. Subcapsular CEUS diagnosed 24 benign and 8 malignant LN lesions. Most lymphomas (6 of 7, 85.7%) exhibited heterogeneous perfusion, with lymphatic tract distortion in the absence of interruption. Reactive hyperplasia LNs manifested as diffuse homogeneous or brush-like perfusion from the subcapsular region to the center, without lymphatic tract distortion. Metastatic LNs had lymphatic tract interruptions. The sensitivity, specificity, consistency and positive and negative predictive values were 77.8%, 95.6%, 90.6%, 87.5% and 91.7%, respectively. For LNs exhibiting uniform enhancement in intravenous CEUS imaging, subcapsular CEUS may help to distinguish between benign and malignant lesions. In particular, lymphatic distortion without interruption may specifically indicate a lymphoma.

Role of gamma probe-assisted intraoperative sentinel lymph node evaluation in predicting axillary breast cancer metastasis after neoadjuvant chemotherapy

OBJECTIVE

Intraoperative sentinel lymph node biopsy is a universally accepted technique to identify patients who are candidates for axillary lymph node dissection during breast cancer surgery. However, there is controversy over its use in patients who underwent preoperative neoadjuvant chemotherapy. This study aimed to examine the diagnostic value of gamma probe-assisted intraoperative sentinel lymph node examination with frozen section in breast cancer patients who had undergone preoperative neoadjuvant chemotherapy.

METHODS

This retrospective study included 94 tumors diagnosed with stage IIA, IIB or IIIA invasive breast cancer with locoregional lymph node metastasis who underwent surgical treatment after neoadjuvant chemotherapy. Intraoperatively, axillary sentinel lymph node sampling was done using radioactive colloid and gamma probe and materials were examined with frozen section method. Patients with positive sentinel nodes underwent axillary resection. Histopathological examination of all surgical samples was done postoperatively.

RESULTS

In 87 of 94 tumors (92.6%), a sentinel lymph node could be identified using the method. The sensitivity, specificity and accuracy of the method for predicting axillary macro metastasis were 85.7, 86.5 and 86.2%, respectively, with 5.7% false negative rate.

CONCLUSIONS

Sentinel lymph node identification using preoperative scintigraphy and intraoperative use of gamma probe seems to be a feasible and efficient method in terms of differentiating patients that require axillary lymph node dissection during breast cancer surgery, even when they have received neoadjuvant chemotherapy. Further large prospective studies allowing subgroup analyses are warranted.