Diagnostic significance of aquaporin-1 in liver tumors

• Published in: Human pathology 2005-11, Vol.36 (11), p.1226-1231
• Main Authors: Mazal, Peter R., Susani, Martin, Wrba, Fritz, Haitel, Andrea
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; AQP-1 immunohistochemistry; Aquaporin 1 - metabolism; Aquaporins; Biological and medical sciences; Biomarkers, Tumor - analysis; Cancer; Capillaries - metabolism; Carcinoembryonic Antigen - metabolism; Carcinoma, Hepatocellular - metabolism; Carcinoma, Hepatocellular - pathology; Cholangiocarcinoma; Cholangiocarcinoma - metabolism; Cholangiocarcinoma - pathology; Cholestasis - metabolism; Cholestasis - pathology; Colleges & universities; Colorectal Neoplasms - metabolism; Colorectal Neoplasms - secondary; Diagnosis, Differential; Female; Gastroenterology. Liver. Pancreas. Abdomen; Hepatocellular carcinoma; Histology; Humans; Immunohistochemistry; Investigative techniques, diagnostic techniques (general aspects); Keratin-7; Keratins - metabolism; Liver; Liver Neoplasms - blood supply; Liver Neoplasms - metabolism; Liver Neoplasms - pathology; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Male; Medical sciences; Middle Aged; Neprilysin - metabolism; Pathology; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Tumors
• ISSN: 0046-8177; 1532-8392
• DOI: 10.1016/j.humpath.2005.09.002

The diagnostic utility of aquaporin (AQP)–1 in liver tumors was tested and compared with other well-established markers. In 30 cholangiocarcinomas (CCs), 20 hepatocellular carcinomas (HCCs), and 10 metastatic colorectal carcinomas (MCCs) of the liver, expression of AQP-1, CD10, cytokeratin (CK) 7, CK20, and polyclonal carcinoembryonic antigen (pCEA) was tested. In addition, staining patterns of CD10 and pCEA were analyzed. To compare the selectivity of AQP-1 and CK7 as possible markers for differentiated cholangiocytes, liver biopsies of cholestatic disease were also analyzed. Aquaporin-1 expression was found in 93% of all CCs compared with 0% of HCC ( P < .000 001) and with 30% of MCC ( P < .01). CD10 was positive in 16.7% of CC compared with 40% of HCC ( P < .04) and to 20% of MCC (not significant). Cytokeratin 7 was positive in 90% of CC compared with 10% of HCC ( P < .000 01) and with 20% of MCC ( P < .0001). Cytokeratin 20 was positive in 90% of MCC compared with 16.7% of CC ( P < .0001) and with 20% of HCC ( P < .000 01). Canalicular staining patterns of CD10 and pCEA were observed in HCC (100% and 89.5%, respectively) but typically not in CC (0% and 6.7%, respectively) and never in MCC. In cholestatic disease, AQP-1 was expressed in differentiated epithelial cells of the bile ducts, whereas CK7-positive hepatocytes of Rappaport zone 1 did not show any AQP-1 reactivity. Therefore, AQP-1 seems to be a highly selective marker for differentiated cholangiocytes and can be very helpful in the differential diagnosis of liver tumors.