Endoscopy 2011; 43 - A171
DOI: 10.1055/s-0031-1292242

Assessment of the ThinPrep method for endoscopic ultrasound-guided fine needle aspirates

Ishida Yusuke 1, Okabe Yoshinobu 1, Taira Tomoki 2, Yamaguchi Tomohiko 2, Kawahara Akihiko 2, Yasumoto Makiko 3, Kaji Ryohei 1, Sugiyama Gen 1, Kitasato Yuhei 4, Kage Masayoshi 2, Kinoshita Hisafumi 4, Tsuruta Osamu 1, Sata Michio 1
  • 1Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, Kurume, Japan
  • 2Department of Pathology, Kurume University Hospital, Kurume, Japan
  • 3Department of Pathology
  • 4Department of Surgery, Kurume University School of Medicine, Kurume, Japan

Background and Aim: The ThinPrep method, one of the liquid-based methods of cytologic preparation is often used for gynecologic samples, but there are few studies about pancreatic samples obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). The objective of this study was to compare the usefulness of the ThinPrep method versus conventional smear methods in pancreatic samples obtained by EUS-FNA.

Patients and Method: Seven patients (5 malignancy: 2 inflammatory change in the pancreas) with pancreatic solid tumors underwent EUS-FNA. All of the obtained samples were submitted to CytoLyt (Cytyc Co., Boxborough, MA) for ThinPrep (Cytyc Co.). Three experienced cytopathologists interpreted the ThinPrep slides in a blind fashion. Furthermore, we conducted a questionnaire for the cytopathologists to compare the differences in interpretation of the techniques between ThinPrep slides and conventional smear slides.

Results: Six of the obtained specimens (6 of 7, 85.7%) were found adequate for cytologic evaluation. Cancer was diagnosed in four samples (4 of 5, 80.0%) obtained from the patients with suspected malignancy. A benign case was confirmed in one patient (1 of 2, 50.0%) with suspected inflammatory change, and the other contained inadequate material. These results are equivalent to the conventional method in our institute. There is no difference in the interpretation of the techniques between ThinPrep slides and conventional smear slides among all of the cytopathologist.

Conclusion: Our result suggests that the ThinPrep method is reliable to diagnose malignancy in EUS-FNA samples, although the sample size was very small. Our result indicates that the ThinPrep method may become a promising tool, because it is much more advantageous for preserving specimens and standardization of cytologic preparation than the conventional smear method. In future studies, we will evaluate the ThinPrep method using a larger sample size.