title: Steroidogenic Factor 1, Pit-1, and Adrenocorticotropic Hormone: A Rational Starting Place for the Immunohistochemical Characterization of Pituitary Adenoma.
abstract: BACKGROUND
  -Pituitary adenoma classification is complex, and diagnostic strategies vary greatly from laboratory to laboratory. No optimal diagnostic algorithm has been defined.
  
  
  OBJECTIVE
  -To develop a panel of immunohistochemical (IHC) stains that provides the optimal combination of cost, accuracy, and ease of use.
  
  
  METHODS
  -We examined 136 pituitary adenomas with stains of steroidogenic factor 1 (SF-1), Pit-1, anterior pituitary hormones, cytokeratin CAM5.2, and α subunit of human chorionic gonadotropin. Immunohistochemical staining was scored using the Allred system. Adenomas were assigned to a gold standard class based on IHC results and available clinical and serologic information. Correlation and cluster analyses were used to develop an algorithm for parsimoniously classifying adenomas.
  
  
  RESULTS
  -The algorithm entailed a 1- or 2-step process: (1) a screening step consisting of IHC stains for SF-1, Pit-1, and adrenocorticotropic hormone; and (2) when screening IHC pattern and clinical history were not clearly gonadotrophic (SF-1 positive only), corticotrophic (adrenocorticotropic hormone positive only), or IHC null cell (negative-screening IHC), we subsequently used IHC for prolactin, growth hormone, thyroid-stimulating hormone, and cytokeratin CAM5.2.
  
  
  CONCLUSIONS
  -Comparison between diagnoses generated by our algorithm and the gold standard diagnoses showed excellent agreement. When compared with a commonly used panel using 6 IHC for anterior pituitary hormones plus IHC for a low-molecular-weight cytokeratin in certain tumors, our algorithm uses approximately one-third fewer IHC stains and detects gonadotroph adenomas with greater sensitivity.
authors.forename: William C
authors.initials: WC
authors.lastname: McDonald
authors.forename: Nilanjana
authors.initials: N
authors.lastname: Banerji
authors.forename: Kelsey N
authors.initials: KN
authors.lastname: McDonald
authors.forename: Bridget
authors.initials: B
authors.lastname: Ho
authors.forename: Virgilia
authors.initials: V
authors.lastname: Macias
authors.affiliation: From the Department of Pathology and Laboratory Medicine, Allina Health Laboratories, Minneapolis, Minnesota (Dr W. C. McDonald); the Research Division, John Nasseff Neuroscience Institute, Minneapolis, Minnesota (Dr Banerji and Ms Ho); the Centre for Urban Epidemiology, Institute for Medical Informatics, Biometry and Epidemiology, University Hospital Essen, Essen, Germany (Dr K. N. McDonald); and the Department of Pathology, University of Illinois at Chicago (Drs Macias and Kajdacsy-Balla).
authors.forename: Andre
authors.initials: A
authors.lastname: Kajdacsy-Balla
mesh_terms: D000236:Adenoma / Q000145:classification / Q000175:diagnosis / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000096:biosynthesis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D016000:Cluster Analysis; D005260:Female; D013006:Growth Hormone / Q000096:biosynthesis; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D007633:Keratins / Q000096:biosynthesis; D008297:Male; D008875:Middle Aged; D010902:Pituitary Gland / Q000378:metabolism / Q000473:pathology; D010911:Pituitary Neoplasms / Q000145:classification / Q000175:diagnosis / Q000378:metabolism*; D011388:Prolactin / Q000096:biosynthesis; D012680:Sensitivity and Specificity; D054339:Steroidogenic Factor 1 / Q000096:biosynthesis*; D013972:Thyrotropin / Q000096:biosynthesis; D050817:Transcription Factor Pit-1 / Q000096:biosynthesis*; D055815:Young Adult
chemical_list: D015415:Biomarkers; C400901:CAM 5.2 antigen; D054339:Steroidogenic Factor 1; D050817:Transcription Factor Pit-1; D007633:Keratins; D000324:Adrenocorticotropic Hormone; D011388:Prolactin; D013972:Thyrotropin; D013006:Growth Hormone