title: Diagnosis of testicular carcinoma in situ '(intratubular and microinvasive)' seminoma and embryonal carcinoma using direct enzymatic alkaline phosphatase reactivity on frozen histological sections.
abstract: OBJECTIVE
  Testis-sparing surgery might benefit quality of life, but can only be applied with histological examination for the presence of invasive germ cell tumour components, and the precursor carcinoma in situ (CIS). Currently, diagnosis is based on paraffin-embedded tissue, therefore a delay in further surgery is mainly unavoidable. The aim was to develop an intraoperative assessment technique using alkaline phosphatase as a marker.
  
  
  RESULTS
  A total of 4093 snap-frozen samples and matched paraffin-embedded tissue of 1500 patients were included. Besides standard haematoxylin and eosin (H&E) staining, the direct enzymatic alkaline phosphatase reactivity (dAP) test (duration 15 min) was applied on frozen sections, while H&E and immunohistochemistry for detection of OCT3/4, α-fetoprotein, human chorionic gonadotrophin (hCG) and cytokeratin was performed on the paraffin-embedded slides. Endothelial cells served as control for the dAP test. Positive staining was found in all CIS (n=965), seminoma (n=1035) and embryonal carcinoma (n=584), either intratubular, microinvasive or invasive. Differentiated non-seminomas (n=1238) showed variable staining. No staining was identified in spermatocytic seminomas (n=5), testicular lymphomas (n=42), testicular rhabdomyosarcomas (n=7), Leydig cell tumours (n=31), Sertoli-cell-only nodules (n=4), (epi) dermoid cyst (n=16), normal testicular parenchyma (n=116), testicular torsion (n=32) and inflammation of the epididymis (n=19). The dAP test results matched H&E-stained parallel sections, as well paraffin-embedded tissue analysis, including immunohistochemistry.
  
  
  CONCLUSIONS
  The dAP test is an informative, reproducible and easy tool to diagnose CIS, (intratubular and microinvasive) seminoma and embryonal carcinoma on frozen tissue sections, being of great value in the context of sparing surgery.
authors.affiliation: Departments of Pathology Urology, Erasmus MC-University Medical Center Rotterdam, Josephine Nefkens Institute, Daniel den Hoed Cancer Center, Rotterdam, the Netherlands.
authors.forename: Hans
authors.initials: H
authors.lastname: Stoop
authors.forename: Wim
authors.initials: W
authors.lastname: Kirkels
authors.forename: Gert R
authors.initials: GR
authors.lastname: Dohle
authors.forename: Ad J M
authors.initials: AJ
authors.lastname: Gillis
authors.forename: Michael A
authors.initials: MA
authors.lastname: den Bakker
authors.forename: Katharina
authors.initials: K
authors.lastname: Biermann
authors.forename: Wolter
authors.initials: W
authors.lastname: Oosterhuis
authors.forename: Leendert H J
authors.initials: LH
authors.lastname: Looijenga
mesh_terms: D000469:Alkaline Phosphatase / Q000032:analysis*; D014408:Biomarkers, Tumor / Q000378:metabolism; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000473:pathology; D018236:Carcinoma, Embryonal / Q000175:diagnosis* / Q000473:pathology; D002454:Cell Differentiation; D005629:Frozen Sections; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D018239:Seminoma / Q000175:diagnosis* / Q000473:pathology; D013736:Testicular Neoplasms / Q000175:diagnosis* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D000469:Alkaline Phosphatase