Influence of Tumor Histology on Preoperative Staging Accuracy of Breast Metastases to the Axilla

Abstract

Histologic confirmation of axillary nodal metastases preoperatively avoids a sentinel node biopsy and enables a one step surgical procedure. The aim of this study was to establish the local positive predictive value of axillary ultrasound (AUS) and guided needle core biopsy (NCB) in axillary staging of breast cancer, and to identify factors influencing yield. A prospective audit of 142 consecutive patients (screening and symptomatic) presenting from 1st December 2008-31st May 2009 with breast lesions categorized R4-R5, who underwent a preoperative AUS, and proceeded to surgery was undertaken. Ultrasound-guided NCB was performed on nodes radiologically classified R3-R5. Lymph node size, number, and morphological features were documented. Yield was correlated with tumor size, grade, and histologic type. AUS/NCB was correlated with post surgical pathologic findings to determine sensitivity, specificity, positive and negative predictive value of AUS and NCB. A total of 142 patients underwent surgery, of whom 52 (37%) had lymph node metastases on histology. All had a preoperative AUS, 51 (36%) had abnormal ultrasound findings. 46 (90%) underwent axillary node NCB of which 24 (52%) were positive. The smallest tumor size associated with positive nodes at surgery was 11.5 mm. The sensitivity of AUS was 65%. Specificity was 81%, with a positive predictive value (PPV) of 67% and negative predictive (NPV) value of 80%. Sensitivity of U/S-guided NCB was 75%, with a specificity of 100%, PPV 100% and NPV 64%. Sensitivity of AUS for lobular carcinoma was 36% versus 76% for all other histologies. Sensitivity of NCB for lobular cancer was 33% versus 79% for all other histologies. The most significant factor producing discordance between preoperative AUS and definitive histologic evidence of lymph node metastasis was tumor type. Accurate preoperative lymph node staging was prejudiced by lobular histology (p< 0.0019).

Population-based study of the sensitivity of axillary ultrasound imaging in the preoperative staging of node-positive invasive lobular carcinoma of the breast

“…In previous single‐centre studies there has been speculation regarding the difference in AUS sensitivity based on tumour subtype. However, all of these studies included significantly lower numbers of patients compared with the present study. The majority of comparative studies, however, showed no difference in AUS sensitivity based on tumour subtype.…”

“…Johnson and colleagues found, however, that in primary lobular carcinoma AUS may be less accurate and a negative result is more likely to be spurious than with primary ductal carcinoma. Hackney and co‐workers demonstrated that the most significant factor in producing discordance between preoperative AUS and definitive histological evidence of lymph node metastasis was the lobular subtype. In addition, Jackson et al .…”

p53 expression in breast cancer predicts tumors with low probability of non‐sentinel nodes infiltration

“…Some nomograms described in the published reports include the pathology subtype as a significant factor predicting NSLN involvement but other reviews have not found this feature significant . Sensitivity of axillary ultrasound has been reported to be much lower in ILC compared to other pathology subtypes (36% vs 76%) . This difference in axillary ultrasound sensibility could be an explanation for our finding: despite performing axillary ultrasound to all our patients previously to surgery, SLN biopsy would have been performed in a high proportion of ILC with a significant axillary neoplastic load as a result of ultrasound inability to detect axillary infiltration in these cases.…”

A comparison of the diagnostic accuracy of magnetic resonance imaging to axillary ultrasound in the detection of axillary nodal metastases in newly diagnosed breast cancer

“…Deficiency in imaging of axillary adenopathy is experienced when evaluating invasive nonductal carcinoma histologic subtypes, such as ILC and invasive mammary carcinoma . Furthermore, limitations in spatial resolution of imaging modalities compromise detection of metastatic deposits too small to characterize on imaging, in our study defined as micrometastases.…”