Utility of Glucose Transporter 1 in the Differentiation of Peritoneal and Pleural Mesothelioma from Non-Malignant Mesothelium
SM Lagana, RN Taub, AC Borczuk. Columbia University Medical Center, New York, NY
Background: Mesothelioma, of either peritoneum or pleura, is a rare malignancy. The diagnosis is often difficult to reach, in part because of the overlap between the morphology of reactive and malignant mesothelial cells. Glucose Transporter 1 (GLUT-1) is a glucose transporter typically found on erythrocytes. Though it stains various carcinomas, it has recently been reported as specific and fairly sensitive in discriminating between malignant pleural mesothelioma and reactive hyperplasia. The application of GLUT-1 staining in peritoneal mesothelioma has not been previously reported.
Design: Tissue microarrays containing 104 malignant peritoneal mesotheliomas and 31 malignant pleural mesotheliomas were studied and slides of 18 benign or reactive mesothelial specimens were stained with a GLUT-1 monoclonal antibody. Two observers scored each for percentage of mesothelial or tumor cells demonstrating positive staining. A cut-off of 5% was set for positivity.
Results: There were no false positives (100% sensitivity) in either the pleura or the peritoneum. Of the total 135 malignancies, 67 demonstrated positive staining (overall 49.6% sensitivity). Malignant versus benign determination had a Chi Square statistic of 16.78, p=.0001. In the peritoneum 52 of 104 malignancies demonstrated positive staining (50% sensitivity), In the pleura, 15 of 31 were positive, showing similar sensitivity in both sites.
Conclusions: As established in pleural disease, GLUT-1 staining is a useful adjunct in the differentiation of peritoneal mesothelioma from benign or reactive mesothelium. Due to modest sensitivity only positive staining is particularly informative. Our experience with pleural mesotheliomas supports what has been previously reported, but showed lower sensitivity. In both instances the utility of the stain was limited by non-specific staining (e.g. in necrotic areas) as well as brightly staining erythrocytes and lymphoid elements. Nonetheless, GLUT-1 can help differentiate malignant mesothelioma from reactive or otherwise benign mesothelium.
Tuesday, March 23, 2010 1:00 PM
Poster Session IV # 249, Tuesday Afternoon