[377] Diagnostic Value of FNA Processed by ThinPrep for Assessment of Axillary Lymph Node Status in Patients with Invasive Carcinoma of Breast
Xin Jing, Elizabeth Wey, Claire W Michael. The University of Michigan Health System, Ann Arbor, MI
Background: Ultrasound-guided FNA has been widely utilized as an important modality in determination of axillary lymph node status during the initial staging and subsequent management of patients with invasive breast carcinoma. Tranditionally, the aspirates are processed as conventional smears. However, in the current study, we evaluated the utility of the use of ThinPrep as a more standard method for detection of axillary lymph node metastasis of invasive breast carcinoma.
Design: A Computer SNOMED Search from the file at our institution between 01/20003 and 08/2011 was conducted to identify patients with invasive breast carcinoma who were worked-up by FNA of axillary lymph node and followed by axillary lymph node dissection. We retrieved a total of 209 FNAs processed by ThinPrep including 193 and 16 diagnostic and non-diagnostic specimens, respectively. The 193 diagnostic specimens consisted of 168 invasive ductal carcinoma (IDC), 15 invasive lobular carcinoma (ILC) and 10 mixed carcinoma(IDC and ILC). Using the histology diagnosis as the golden standard, the diagnostic parameters were determined. Slides from cyto-histologic discrepant cases were re-reviewed.
Results:
| Parameters | IDC | ILC/Mixed carcinoma | Total |
| True positive | 110 | 16 | 126 |
| True negative | 32 | 4 | 36 |
| False positive | 0 | 0 | 0 |
| False negative | 26 | 5 | 31 |
| Sensitivity (%) | 81 | 76 | 80 |
| Specificity (%) | 100 | 100 | 100 |
| PPV (%) | 100 | 100 | 100 |
| NPV (%) | 53 | 44 | 54 |
| Accuracy (%) | 84 | 80 | 84 |