This document discusses special chemistry tests and tumor markers. It defines special chemistry as tests not part of routine panels, including electrophoresis, urine chemistry, and radioimmunoassay. It describes the sensitivity and specificity of troponin, myoglobin, and pro-brain natriuretic peptide for detecting heart damage and failure. It also discusses various tumor markers like CEA, AFP, PSA, and their uses for screening, monitoring cancer survivors, and diagnosing certain tumors. Guidelines are provided for ordering and interpreting tumor marker tests. Common detection techniques include serology, enzyme assays, immunoassays, and genetic analysis.