title: SALL4 is a useful marker in the diagnostic work-up of germ cell tumors in extra-testicular locations.
abstract: We evaluated the impact of SALL4 immunostaining on the diagnosis of non-testicular germ cell tumors in clinical practice. We retrieved cases of six mediastinal, five retroperitoneal, and eight central nervous system tumors that were diagnosed as extra-testicular germ cell tumors (GCT) as well as 20 location-matched non-GCT. Each tumor we stained immunohistochemically for PLAP, OCT3-4, CD117, CD30, FP, -HCG, glycipan-3, SALL 4, AE1-AE3, EMA, CK7, CK20, CD45, TTF1, vimentin, and GFA. The results were assessed independently by two experienced pathologists. In 18 of 19 cases (95 %), SALL4 was strongly expressed, either homogenously (16 cases) or focally (two cases). All other GCT markers (PLAP, OCT3-4, CD117, CD30, FP, -HCG, and glycipan-3) were expressed with a lower frequency (21-69 %). The specificity of SALL4 was 100 % in our series. SALL4 should be part of the first panel of antibodies for the diagnosis of a midline tumor (mediastinal, retroperitoneal, or pineal) in patients under the age of 40 years. We also recommend that SALL4 be used in the diagnostic work-up of undifferentiated tumors in any location and in patients of any age. When a tumor is SALL4 positive, in case of need the diagnosis of germ cell tumor can be further confirmed using additional conventional markers.
authors.affiliation: Centre de Pathologie Amiens Picardie, 51 rue Jeanne d'Arc, 80000 Amiens, France. philippecamparo@gmail.com
authors.forename: Philippe
authors.initials: P
authors.lastname: Camparo
authors.forename: Eva Maria
authors.initials: EM
authors.lastname: Comperat
mesh_terms: D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009373:Neoplasms, Germ Cell and Embryonal / Q000175:diagnosis* / Q000378:metabolism; D012680:Sensitivity and Specificity; D014157:Transcription Factors / Q000032:analysis / Q000096:biosynthesis; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C472575:SALL4 protein, human; D014157:Transcription Factors