Usefulness of KL-6 in the subtyping of intraductal papillary mucinous neoplasia of the pancreas, including carcinoma, dysplasia, and hyperplasia

• Published in: Medical molecular morphology Vol. 48; no. 2; pp. 85 - 91
• Main Authors: Ohtsuki, Yuji, Watanabe, Ryohei, Kimura, Masashi, Nomura, Katsuyoshi, Maeda, Tomoharu, Kito, Katsumi, Takeji, Miyuki, Lee, Gang-Hong, Furihata, Mutsuo
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01.06.2015; Springer Nature B.V
• Subjects: Adenocarcinoma, Mucinous - metabolism; Adenocarcinoma, Mucinous - pathology; Aged; Aged, 80 and over; Anatomy; Antibodies - immunology; Biomarkers; Biomarkers - metabolism; Carcinoma, Pancreatic Ductal - metabolism; Carcinoma, Pancreatic Ductal - pathology; Carcinoma, Papillary - metabolism; Carcinoma, Papillary - pathology; Female; Humans; Hyperplasia - metabolism; Hyperplasia - pathology; Immunohistochemistry; Immunohistochemistry - methods; Male; Medicine; Medicine & Public Health; Middle Aged; Molecular Medicine; Mucin-1 - metabolism; Neoplasm Invasiveness - pathology; Original Paper; Pancreas; Pancreatic Neoplasms - metabolism; Pancreatic Neoplasms - pathology; Pathology; Tumors; Immunohistochemistry; KL-6; Pancreas; Subtype; Intraductal papillary mucinous neoplasia
• ISSN: 1860-1480; 1860-1499
• DOI: 10.1007/s00795-014-0080-1

KL-6 is known as a useful serum biomarker of the disease activity in interstitial pneumonias. We investigated its usefulness as a biomarker for subtyping intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. IPMNs are generally divided into 4 subtypes, namely pancreatobiliary (PB), intestinal (INT), gastric (GS), and oncocytic (ONC). Aside from the KL-6 antibody, the MUC1, MUC2, MUC5AC, MUC6, and MIB-1 antibodies were also examined. Eighteen IPMN cases were examined, including 12 cases of intraductal papillary mucinous carcinomas (IPMCs) simultaneously associated with dysplasia (IPMDs) and hyperplasia (IPMHs) and 6 IPMD cases with IPMH. KL-6 antibody was positive in the 8 IPMC cases, corresponding to a MUC2-negative PB subtype, but negative in 4 IPMC cases, corresponding to the INT subtype, which is positive for MUC2. IPMD of moderate-to-severe degree positively stained for the KL-6 antibody in the IPMC cases of the PB subtype but not in those of the INT subtype. The IPMH cases were mostly negative for KL-6, similar to the mild IPMD cases. In the 6 cases of mild IPMD and/or IPMH, KL-6 and MUC2 expressions were mostly negative. In conclusion, the KL-6 antibody is immunohistochemically a good biomarker of the PB subtype of IPMC, but not the INT subtype. Identifying IPMN subtypes based on KL-6 stainability would be useful. Clinicopathological studies with more IPMC cases might be needed for further progress in this field of study.