The expression and clinical effects of alpha-methylacyl-CoA racemase (AMACR/ P504S) as an immunohistochemical marker in malign pleural mesothelioma.

Abstract

Alpha-methylacyl-CoA racemase (AMACR), an intracellular enzyme involved in lipid metabolism, has emerged as an immunohistochemical marker for many types of cancer. Recent studies about the role of lipid metabolism in pathogenesis of mesothelioma have brought up some positive results. This study was conducted to investigate AMACR expression in the diagnosis of malignant pleural mesothelioma (MPM) and the correlation of this marker with clinical characteristics and survival. The clinicopathologic characteristics and resection materials of 71 patients were reviewed retrospectively. AMACR expression was evaluated immunohistochemically. The correlations among AMACR expression, clinicopathologic factors, and survival were investigated. AMACR expression was detected in 42.3% of the study group. The specificity and sensitivity of AMACR immunostaining in detecting mesothelioma were 41.1% and 42.3%, respectively. AMACR-positive and negative groups were similar for age, sex, smoking history, tumor diameter, lymph node involvement, differentiation, T-N factor, and stage. Overall survival was not significantly different between the groups, either. The sensitivity of immunostaining was not high enough to use AMACR as a diagnostic tool in MPM. AMACR expression did not have a prognostic value in MPM, either.