Evaluation of the diagnostic efficacy of liquid-based cytology obtained via percutaneous ultrasound-guided fine-needle aspiration for pancreatic masses: a large tertiary center's 8-year experience

Abstract

Purpose: There were limited data on the diagnostic efficacy of liquid-based cytology (LBC) for pancreatic tissues acquired by percutaneous ultrasound-guided fine-needle aspiration (US-FNA). This study aimed to evaluate the diagnostic value of LBC acquired via percutaneous US-FNA for pancreatic tumors compared with LBC combined with smear cytology (SC).

Methods: A retrospective database search (January 2014 and February 2022) was performed for patients who underwent percutaneous US-FNA with both LBC and SC. Clinical and pathological data were collected from 298 patients; eventually, 251 cases met the inclusion criteria. Diagnostic accuracy, sensitivity (SEN), specificity (SPE), positive predictive value (PPV) and negative predictive value (NPV) were compared. Rapid on-site evaluation (ROSE) was not available in all cases.

Results: Based on the pancreaticobiliary cytology guidelines published by the Papanicolaou Society of Cytopathology, 224 (89.2%), 13 (5.2%) and 14 (5.6%) cases were diagnosed as malignant, pre-malignant and benign lesions, respectively. The diagnostic accuracy of the LBC + SC (88.5%) was better than that of LBC (87.3%) but without statistical significance (P = 0.125). The SEN, SPE, PPV and NPV were 87.5%, 85.2%, 98.0% and 45.1%, respectively, in the LBC group and 88.8%, 85.2%, 98.0% and 47.9%, respectively, in the LBC + SC group. According to univariate and multivariate analyses, there were no factors have significant association with the diagnostic sensitivity of LBC.

Conclusions: LBC obtained via percutaneous US-FNA provides good diagnostic value for pancreatic lesions and there was no significant difference between the diagnostic accuracy of LBC and LBC + SC when ROSE was unavailable.

Keywords: Liquid-based cytology; Pancreatic tumor; Ultrasound-guided fine-needle aspiration.

Fig. 1

Flow chart of selecting the included patients

Fig. 2

Ultrasound-guided FNA of pancreatic neoplasm in a 63-year-old woman. a Grayscale image showed a hypoechoic mass with irregular margins in the pancreatic neck; b color Doppler showed abundant color signals inside the mass; c pre-contrast Color Doppler revealed the splenic artery partially wrapped by the mass, with the bifurcation of the celiac artery involved; d mild enhancement was shown in the mass at the 12th second in the early arterial phase of CEUS, with the splenic artery wrapped in; e at the 28th second in the arterial phase, homogeneous and slightly low enhancement was revealed in the mass; f At 222 s in the venous phase, clear hypo-enhancement and washout of the mass were observed; g US-guided biopsy using a 20-gauge needle avoiding the splenic vessel, with the needle tip and the needle track clearly visible inside the target lesion; h, i SC and LBC confirmed the presence of PDAC (h SC, i LBC).

Fig. 3

US-guided FNA of the tumor located in the body of pancreas. a supine position was preferred and the probe was in transverse scan; b the boundary of the tumor was more distinct in CEUS and there were no necrotic areas; c, d illustration of transabdominal approach (advance between stomach and transverse colon) on abdominal cross section