Immunohistochemical Detection of Monocarboxylate Transporters (MCT) and GLUT-1 in Pleural Malignant Mesothelioma and Reactive Mesothelial Hyperplasia: A Useful Tool for the Differential Diagnosis
M Hamasaki, A Mogi, K Nabeshima, N Uesugi, K Tamura, A Iwasaki, T Shirakusa, H Iwasaki. Fukuoka University Hospital & School of Medicine, Fukuoka, Japan; Fukuoka University Hospital & School of Medicine, Fukoka, Japan; National Hospital Organization Kyushu Medical Center, Fukoka, Japan; Fukusei-Kai Hospital, Fukoka, Japan
Background: Malignant tumor cells are highly proliferative and dependent on glycolysis for energy. Glucose transporter (GLUT)-1 enhances glucose influx in most human tumors. On the other hand, glucose metabolism via anaerobic glycolysis results in the production of large quantities of lactate, which cause intracellular acidosis and thus should be pumped out of cells by monocarboxylate transporters (MCT). Malignant mesothelioma (MM) is a highly aggressive neoplasm, and early diagnosis is critical for its treatment. However, differentiation of MM from reactive mesothelial hyperplasia (RMH) is sometimes difficult especially in small biopsy specimens. In this study, we examined whether immunohistochemical detection of MCT-1, MCT-4 and GLUT-1 could be a useful aid in differentiation between MM and RMH.
Design: We examined immunohistochemical expressions of MCT-1, MCT-4 and GLUT-1 in 34 cases of MM (22 epithelioid, 4 sarcomatoid, 7 biphasic, and 1 lymphohistiocytoid) and 20 cases of RMH.
Results: GLUT-1 expression was seen in 56% of MM and none of RMH. However, the expression rates (% of positive cells) were low: positive cells were less than 50% in 84% of the positive cases. MCT-1 was positive in all MM, and 79% of MM vs 15% of RMH showed high expression (≥50%) scores. MCT-4 expression was found in 88% of MM and none of RMH. Seventy-three percent of the positive cases showed high expression rates.
Conclusions: Combined immunohistochemical detection of MCT-1, MCT-4 and GLUT-1 is more sensitive and specific than that of GLUT-1 alone to descriminate between MM and RMH, and useful in early diagnosis of MM in small surgical specimens.
Tuesday, March 23, 2010 1:00 PM
Poster Session IV # 250, Tuesday Afternoon