Preoperative axillary lymph node staging by ultrasound-guided cytology using a four-level sonographic score

Determination of axillary lymph node status by fine-needle aspiration: preoperative axillary staging vs. postoperative surveillance for breast cancers

Background

Despite the common use of ultrasound (US)-guided fine-needle aspiration (FNA) for axillary node (AN) in breast cancer patients, only a limited number of studies are available regarding the diagnostic performance of AN-FNA according to the suspicion level based on US findings. This study compares the outcomes of US-guided AN-FNA in breast cancer patients, differentiating between those undergoing staging and surveillance.

Methods

A cross-sectional retrospective study with retrospective analysis was conducted on 767 consecutive AN-FNA procedures performed in 2017 at Samsung Medical Center in Seoul, with 654 for staging and 113 for surveillance in breast cancer patients. The radiologists performed axillary US and the specific finding was prospectively classified into the AN-reporting and data system (AN-RADS) category 3-5 before FNA. The malignancy rate of each category was evaluated. The chi-square test, with or without Bonferroni correction, or Fisher's exact test was used to compare the malignancy rates between the staging and surveillance groups for each category.

Results

Among the 767 AN-FNAs, 424 (55.3%) were malignant. The malignancy rate was significantly higher in the staging group (59.5%) than in the surveillance group (31.0%, P<0.0001). The distribution of AN-RADS categories differed between the groups (P=0.015), with 4A being the most common. The malignancy rates in categories 3, 4A, 4B, 4C, and 5 were as follows: 5.6%, 36.0%, 77.4%, 87.7%, and 98.4% in the staging group, and 0.0%, 9.7%, 53.3%, 88.9%, and 100% in the surveillance group. The malignancy rate was significantly different between the two groups only in category 4A (P=0.0001).

Conclusions

AN-FNA according to AN-RADS category appears to be an appropriate method for determination of axillary nodal status. Overall malignancy rate of AN-FNA in breast cancer patients was higher in the staging group than in the surveillance group. According to the suspicion level, the difference between two groups was significant only in category 4A.

A Nomogram Combined Radiomics and Kinetic Curve Pattern as Imaging Biomarker for Detecting Metastatic Axillary Lymph Node in Invasive Breast Cancer

Objective: To construct and validate a nomogram model integrating the magnetic resonance imaging (MRI) radiomic features and the kinetic curve pattern for detecting metastatic axillary lymph node (ALN) in invasive breast cancer preoperatively. Materials and Methods: A total of 145 ALNs from two institutions were classified into negative and positive groups according to the pathologic or surgical results. One hundred one ALNs from institution I were taken as the training cohort, and the other 44 ALNs from institution II were taken as the external validation cohort. The kinetic curve was computed using dynamic contrast-enhanced MRI software. The preprocessed images were used for radiomic feature extraction. The LASSO regression was applied to identify optimal radiomic features and construct the Radscore. A nomogram model was constructed combining the Radscore and the kinetic curve pattern. The discriminative performance was evaluated by receiver operating characteristic analysis and calibration curve.

Results: Five optimal features were ultimately selected and contributed to the Radscore construction. The kinetic curve pattern was significantly different between negative and positive lymph nodes. The nomogram model showed a better performance in both training cohort [area under the curve (AUC) = 0.91, 95% CI = 0.83–0.96] and external validation cohort (AUC = 0.86, 95% CI = 0.72–0.94); the calibration curve indicated a better accuracy of the nomogram model for detecting metastatic ALN than either Radscore or kinetic curve pattern alone.

Conclusion: A nomogram model integrated the Radscore and the kinetic curve pattern could serve as a biomarker for detecting metastatic ALN in patients with invasive breast cancer.

Diagnostic Accuracy of Fine-Needle Aspiration Cytology and Core-Needle Biopsy in the Assessment of the Axillary Lymph Nodes in Breast Cancer-A Meta-Analysis

Background: The present study aims to evaluate the diagnostic accuracy between ultrasonography-guided fine-needle aspiration cytology (US-FNAC) and core needle biopsy (CNB) of axillary lymph nodes (ALNs) in patients with breast cancer through a meta-analysis and a diagnostic test accuracy (DTA) review. Methods: The present meta-analysis and DTA review included 67 eligible studies. The diagnostic accuracy of various preoperative assessments, including US-FNAC and CNB, was evaluated for ALNs assessments in patients with breast cancer. In addition, a subgroup analysis based on methods of cytologic preparation was performed. In the DTA review, the sensitivity, specificity, diagnostic odds ratio (OR) and area under the curve (AUC) on the summary receiver operating characteristic (SROC) curve were calculated. Results: The diagnostic accuracy of the preoperative assessments of ALNs was 0.850 (95% confidence interval (CI) 0.833–0.866) for patients with breast cancer. The diagnostic accuracy of CNB was significantly higher than that of US-FNAC (0.896, 95% CI 0.844–0.932 vs. 0.844, 95% CI 0.825–0.862; p = 0.044 in a meta-regression test). In the subgroup analysis based on cytologic preparation, the diagnosis accuracies were 0.860, 0.861 and 0.859 for the methods of conventional smear, liquid-based preparation and cell block, respectively. In the DTA review, CNB showed higher sensitivity than US-FNAC (0.849 vs. 0.760). However, there was no difference in specificity between US-FNAC and CNB (0.997 vs. 1.000). US-FNAC with liquid-based preparation and CNB showed the highest diagnostic OR and AUC on the SROC, respectively. Conclusion: Both US-FNAC and CNB are useful in preoperative assessments of ALNs in patients with breast cancer. Although the most sensitive test was found to be CNB in this study, there was no difference in specificity between various preoperative evaluations and the application of US-FNAC or CNB may be impacted by various factors.

Outcomes of ultrasound-guided axillary lymph node sampling in the absence of primary breast cancer

PURPOSE

To evaluate outcomes of lymph node sampling in patients with suspicious axillary nodes without a diagnosis of breast cancer.

MATERIALS AND METHODS

We retrospectively identified all axillary ultrasound-guided sampling performed at our institution from 2003 to 2016 in patients. without malignancy.

RESULTS

Seventy-eight lymph nodes met inclusion criteria. Two of the 78 sampled nodes (2.6%) were malignant.

CONCLUSION

Sampling of suspicious nodes in patients without a history of breast cancer rarely yields malignancy. The malignancy rate approaches the 2% BIRADS 3 threshold. Further data may demonstrate that short-interval imaging follow-up is a safe alternative to sampling in this cohort.