The sensitivity of conventional cytology for the detection of malignant cells in pleural effusion is insufficient. GLUT1 and CAIX are the hallmarks of metabolic change in cancer cells. The aim of this study was to evaluate the usefulness of GLUT1 and CAIX expression to the detection of cancer cells in pleural effusions.
A total of 150 pleural effusions were subjected to immunocytochemical staining for GLUT1 and CAIX expression. According to their cytological diagnosis and etiology, these included 58 benign effusions, 38 probable malignant effusions, 7 atypical effusions, and 47 malignant effusions,.
None of the benign effusions showed GLUT1 or CAIX expression, but probable malignant effusions and malignant effusions significantly expressed GLUT1 and CAIX with a positive result in 74.5% and 63.8% of the malignant effusions, respectively, with 100% specificity. When the combination of both markers was evaluated, GLUT1 and CAIX displayed a higher diagnostic performance, ie, a sensitivity of 76.6%, specificity of 100%, and accuracy of 89.5%. A statistically significant positive correlation between GLUT1 and CAIX expression was observed. In addition, 18% of cases with cells resembling mesothelial cell hyperplasia in probable malignant effusions and 71.4% of cases with atypical cells of uncertain significance in atypical effusions were highlighted on GLUT1 or/and CAIX immunocytochemical stains.
Immunocytochemical staining for GLUT1 and CAIX may be a complementary tool for the detection of malignant pleural effusions and is helpful in distinguishing cancer cells from reactive mesothelial cells. A combination of GLUT1 and CAIX immunocytochemical staining can give a higher diagnostic performance. Cancer (Cancer Cytopathol) 2011;. © 2011 American Cancer Society.