Axillary ultrasound and fine-needle aspiration in the preoperative evaluation of the breast cancer patient: an algorithm based on tumor size and lymph node appearance.

OBJECTIVE: The objective of our study was to evaluate the utility of ultrasound-guided fine-needle aspiration (FNA) of the axillary lymph nodes in breast cancer patients depending on the size of the primary tumor and the appearance of the lymph nodes. SUBJECTS AND METHODS: Data were collected about tumor size, lymph node appearance, and the results of ultrasound-guided FNA and axillary surgery of 224 patients with breast cancer undergoing 226 ultrasound-guided FNA. Lymph nodes were classified as benign if the cortex was even and measured < 3 mm, indeterminate if the cortex was even but measured ≥ 3 mm or measured < 3 mm but was focally thickened, and suspicious if the cortex was focally thickened and measured ≥ 3 mm or the fatty hilum was absent. The results of ultrasound-guided FNAs were analyzed by the sonographic appearance of the axillary lymph nodes and by the size of the primary tumor. The sensitivity and specificity of ultrasound-guided FNA were calculated with axillary surgery as the reference standard. The sensitivity and specificity of axillary ultrasound to predict the ultrasound-guided FNA result were calculated. RESULTS: Of the 224 patients, 51 patients (23%) had a positive ultrasound-guided FNA result, which yields an overall sensitivity of 59% and specificity of 100%. The sensitivity of ultrasound-guided FNA was 29% in patients with primary tumors ≤ 1 cm, 50% in patients with tumors > 1 to ≤ 2 cm, 69% in patients with tumors > 2 to ≤ 5 cm, and 100% in patients with tumors > 5 cm. The sensitivity of ultrasound-guided FNA in patients with normal-appearing lymph nodes was 11%; indeterminate lymph nodes, 44%; and suspicious lymph nodes, 93%. Sonographic characterization of lymph nodes as suspicious or indeterminate was 94% sensitive and 72% specific in predicting positive findings at ultrasound-guided FNA. CONCLUSION: Ultrasound-guided FNA of the axillary lymph nodes is most useful in the preoperative assessment of patients with large tumors (> 2 cm) or lymph nodes that appear abnormal.

Axillary lymph nodes: US-guided fine-needle aspiration for initial staging of breast cancer--correlation with primary tumor size.

PURPOSE: To retrospectively assess the sensitivity and specificity of ultrasonographic (US)-guided fine-needle aspiration (FNA) of axillary lymph nodes for preoperative staging of breast cancer across a range of primary tumor sizes, by using histologic findings as a reference standard. MATERIALS AND METHODS: Institutional review board approval was obtained for this HIPAA-compliant study; informed consent was waived. US-guided FNA results in 74 patients with breast cancer (75 axillae) were compared with final pathologic results. Lymph nodes were classified as benign, indeterminate, or suspicious on the basis of US characteristics at retrospective review. US-guided FNA in the most suspicious node at US, or the largest node if all appeared benign, was performed. Final pathologic results (sentinel lymph node biopsy [SNB] or axillary lymph node dissection [ALND]) were compared with US and preoperative US-guided FNA results. Results were assessed according to tumor size. Sensitivity, specificity, and positive predictive value of US and US-guided FNA were calculated. RESULTS: Primary tumor sizes were 0.3-12 cm (mean, 3 cm). Patient age range was 31-81 years (mean age, 51 years). Sensitivity of US-guided FNA for predicting positive results at ALND or SNB was 71%-75%. Specificity was 100%. Sensitivity of US-guided FNA increased with primary tumor size. CONCLUSION: US-guided FNA of axillary lymph nodes in patients with newly diagnosed breast cancer had a sensitivity that increased with increasing size of the primary tumor.

BI-RADS lexicon for US and mammography: interobserver variability and positive predictive value.

PURPOSE: To retrospectively evaluate interobserver variability between breast radiologists by using terminology of the fourth edition of the Breast Imaging Reporting and Data System (BI-RADS) to categorize lesions on mammograms and sonograms and to retrospectively determine the positive predictive value (PPV) of BI-RADS categories 4a, 4b, and 4c. MATERIALS AND METHODS: Institutional review board approval was obtained; informed consent was not required. This study was HIPAA compliant. Ninety-four consecutive lesions in 91 women who underwent image-guided biopsy comprised 59 masses, 32 calcifications, and three masses with calcification. Five radiologists retrospectively reviewed these lesions. Each observer described each lesion with BI-RADS terminology and assigned a final BI-RADS category. Interobserver variability was assessed with the Cohen kappa statistic. A pathologic diagnosis was available for all 94 lesions; 30 (32%) were malignant and 64 (68%) were benign. Pathologic analysis of benign lesions was performed on tissue obtained with image-guided core-needle biopsy. In cases referred for excisional biopsy after needle biopsy because of atypia or discordance, final surgical pathologic analysis was used for correlation with imaging findings. PPV for category 4 or 5 lesions was determined for all readers combined. RESULTS: For ultrasonographic (US) descriptors, substantial agreement was obtained for lesion orientation, shape, and boundary (kappa = 0.61, 0.66, and 0.69, respectively). Moderate agreement was obtained for lesion margin and posterior acoustic features (kappa = 0.40 for both). Fair agreement was obtained for lesion echo pattern (kappa = 0.29). For mammographic descriptors, moderate agreement was obtained for mass shape, mass margin, and calcification distribution (kappa = 0.48, 0.48, and 0.50, respectively). Fair agreement was obtained for calcification description (kappa = 0.32). Slight agreement was obtained for mass density (kappa = 0.18). Fair agreement was obtained for final assessment category (kappa = 0.28). PPVs of BI-RADS category 4 and 5 assignments were as follows: category 4a, six (6%) of 102; category 4b, 17 (15%) of 110; category 4c, 48 (53%) of 91; and category 5, 71 (91%) of 78. CONCLUSION: Interobserver agreement with the new BI-RADS terminology is good and validates the US lexicon. Subcategories 4a, 4b, and 4c are useful in predicting the likelihood of malignancy.

Characterization of breast masses with sonography: can biopsy of some solid masses be deferred?

OBJECTIVE: To determine whether sonography can be used to categorize some solid breast masses as probably benign so that biopsy can be deferred. METHODS: We prospectively characterized 844 sonographically visible solid breast masses referred for biopsy. Mammographic and sonographic features of the masses were recorded, and all masses were categorized by American College of Radiology Breast Imaging Reporting and Data System classification before biopsy. Of the 844 masses, 148 were categorized as probably benign (Breast Imaging Reporting and Data System category 3). Sonographically guided biopsy (n = 804) or fine-needle aspiration (n = 40) was performed for pathologic correlation. RESULTS: Of the 148 masses that met the sonographic criteria for probably benign masses, there was 1 malignancy, for a negative predictive value of 99.3%. CONCLUSIONS: Follow-up can be an acceptable alternative to biopsy for sonographically probably benign solid masses.