title: Testicular Hypoplasia Is Driven by Defective Vascular Formation.
abstract: OBJECTIVE
  To determine if vanishing testis could result from a fault in embryological development as a result of an arrest in endothelial cell migration rather than secondary to just a random physical torsion/twist. A testicular nubbin or vanishing testis is considered to be secondary to a neonatal torsion and is usually associated with a hemosiderin deposit.
  
  
  METHODS
  Cases of vanishing testis excision were compared with age-matched controls from cadaveric testes without known genitourinary pathology. To assess the testis microvasculature, we performed immunohistochemistry using an automated staining platform with controlled and standardized conditions and positive and negative controls. We used cluster of differentiation (CD) 34 to stain blood vessel endothelium, stem cells, and interstitium; CD31 (all endothelium); and D2-40 for lymphatic endothelium. Morphometric analysis was carried out, % of the total tissue with CD31 and CD34 positive stain was assessed, and the number of the lymphatic vessels (D2-40) per mm2was counted.
  
  
  RESULTS
  Of the 10 cases, 7 had evidence of hemosiderin deposit and calcification. The % distribution of CD34 in controls was higher, 13.4 ± 3.1 (mean ± standard deviation), compared to nubbin cases, 4.5 ± 2.9 (P ≤ .001). The % distribution of CD31 was 2.8 ± 0.83 in controls compared to 1.31 ± 0.60 in cases (P ≤ .001). The lymphatic distribution was similar in both groups, cases (6.4 ± 4.3 n/mm2) and controls (6.4 ± 1.7 n/mm2) (P = .99) CONCLUSION: This histopathological study suggests that disturbances in endothelial development may be a contributing factor leading to testicular hypoplasia and a resultant nubbin testis, independent of a physical torsion event.
authors.affiliation: Division of Pediatric Urology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA. Electronic address: pankajdangle@gmail.com.
authors.forename: Pankaj
authors.initials: P
authors.lastname: Dangle
authors.affiliation: Department of Pathology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Salgado
authors.affiliation: Department of Pathology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA.
authors.forename: Miguel
authors.initials: M
authors.lastname: Reyes-Mugica
authors.affiliation: Division of Pediatric Urology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA.
authors.forename: Francis
authors.initials: F
authors.lastname: Schneck
authors.affiliation: Division of Pediatric Urology, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA.
authors.forename: Michael
authors.initials: M
authors.lastname: Ost
authors.affiliation: Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA.
authors.forename: Sunder
authors.initials: S
authors.lastname: Sims-Lucas
mesh_terms: D018952:Antigens, CD34 / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D018450:Disease Progression; D004730:Endothelium, Vascular / Q000002:abnormalities / Q000254:growth & development; D006061:Gonadal Dysgenesis, 46,XY / Q000601:surgery; D006485:Hemosiderin / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D042601:Lymphatic Vessels / Q000002:abnormalities* / Q000000981:diagnostic imaging; D008297:Male; D055806:Microvessels / Q000000981:diagnostic imaging / Q000254:growth & development*; D009919:Orchiectomy; D010865:Pilot Projects; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D012189:Retrospective Studies; D013733:Testicular Diseases / Q000378:metabolism / Q000473:pathology*; D013737:Testis / Q000002:abnormalities / Q000098:blood supply* / Q000601:surgery
chemical_list: D018952:Antigens, CD34; D015415:Biomarkers; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D006485:Hemosiderin