[388] Computed Tomography-Guided Fine Needle Aspiration and Needle Core Biopsy: Which Specimen Type Yields Diagnostic Results?

Yoshiyuki Kikuchi, Douglas Larsen, Lubna Sayage-Rabie. Texas A&M University Health Science Center and Scott & White Memorial Hospital, Temple, TX

Background: Computed tomography (CT) guided sampling of deep seated lesions throughout the body has become a standard diagnostic procedure. Sampling methods of such lesions include both fine needle aspiration (FNA) cytology and needle core biopsy (NCB). Previous studies have shown contradictory results in sensitivity and specificity of these modalities, and few studies have compared these procedures among different interventional radiologists. The aim of this study is to compare the diagnostic success rates of CT-guided FNA versus NCB at our institution.
Design: We retrospectively reviewed a total of 141 patient samples from January 2008 to December 2009 in which both FNA and NCB material was available. Sample procurement was performed by five interventional radiologists. These consisted of lung (105), liver (16), and lymph node (20) cases. Unsatisfactory FNA cases were excluded. FNA samples underwent immediate assessment and follow-up evaluation by a cytopathologist. Those obtained by NCB underwent histologic evaluation. The final diagnosis was confirmed by surgical resection or clinical findings.
Results: FNA cytology identified 100 of 109 (92%) malignant lesions with a false negative rate of 9%. NCB histology detected 87 of 109 (80%) malignant lesions with a false negative rate of 25%. Twenty-six cases had corresponding benign cytology and histology. Six cases were unsatisfactory by FNA; of those, 2 were benign and 4 were malignant by NCB. There was 72% correlation rate between FNA and CNB. More accurate tumor classification was possible in 4 cases on NCB. Only minor variations were noted based on which interventional radiologist was performing the procedure.

		NCB		Site
		Positive	Negative
FNA	Positive	63	19	Lung
		6	3	Liver
		9	0	Lymph Node
		78	22	Total
	Negative	6	14	Lung
		1	5	Liver
		2	7	Lymph Node
		9	26	Total

Conclusions: Both CT-guided FNA and NCB can serve as sampling methods of deep seated lesions. While FNA allows for immediate assessment and biopsy guidance, NCB can result in more abundant tissue for complete histologic evaluation. In our study, FNA had a higher malignancy detection rate with a lower false negative rate when compared to NCB. This is likely due to the use of immediate assessment at our institution. Thus, the role of FNA cytology is an important diagnostic tool; however, utilization of each modality ultimately depends on the proper clinical setting and the experience of the interventional radiologist and pathologist.
Category: Cytopathology

Wednesday, March 21, 2012 1:00 PM

Poster Session VI # 95, Wednesday Afternoon