title: Novel quantitative analysis of the S100P protein combined with endoscopic ultrasound-guided fine needle aspiration cytology in the diagnosis of pancreatic adenocarcinoma.
abstract: Specimens obtained with endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) are often tiny and fragmented leading to an inconclusive and doubtful diagnosis. To overcome the limitations of EUS-FNA in the cytological diagnosis of pancreatic adenocarcinoma (PCA), we evaluated whether quantification of the S100P protein combined with EUS-FNA reliably discriminated between PCA and benign pancreatic lesions (BPL). A high sensitivity sandwich ELISA for S100P protein was developed to aid in the detection of PCA in small samples obtained using EUS-FNA. After experimental verification of the sandwich ELISA with cell lines and mouse xenograft tumors, 27 consecutive patients with suspicious PCA who underwent EUS-FNA were enrolled in the present study examining the combination of S100P protein assessment and EUS-FNA cytology. The concentration of the S100P protein in EUS-FNA samples from the PCA group was significantly higher than that in the BPL group (P=0.04). Using receiver operating characteristic curve analysis, we determined the S100P protein cut-off value for PCA diagnosis to be 99.8 ng/ml. The S100P protein levels combined with EUS-FNA cytology to detect PCA showed the following diagnostic values: sensitivity, 94.4% [95% confidence interval (CI), 75.7-99.1%]; specificity, 88.9% (95% CI, 51.8-99.7%); positive predictive value, 94.4% (95% CI, 72.7-99.9%); negative predictive value, 88.9% (95% CI, 51.8-99.7%); accuracy, 92.6% (95% CI, 75.7‑99.1%); and area under the curve, 0.92 (95% CI, 0.79-1.00). We established a novel quantitative analysis for the S100P protein in EUS-FNA samples which, when combined with EUS-FNA cytology, could provide promising results for the reliable diagnosis of PCA.
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Chiba
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Hiroo
authors.initials: H
authors.lastname: Imazu
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kato
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ikeda
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Arakawa
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kato
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Sumiyama
authors.affiliation: Department of Oncology, The Jikei University School of Medicine, Tokyo 105-8461, Japan.
authors.forename: Sadamu
authors.initials: S
authors.lastname: Homma
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002135:Calcium-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D045744:Cell Line, Tumor; D003581:Cytodiagnosis; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D051379:Mice; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D009369:Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D010865:Pilot Projects; D023041:Xenograft Model Antitumor Assays
chemical_list: D002135:Calcium-Binding Proteins; D009363:Neoplasm Proteins; C103003:S100P protein, human