title: Overexpression of Vascular Endothelial Growth Factor A in Invasive Micropapillary Colorectal Carcinoma.
abstract: BACKGROUND
  Invasive micropapillary carcinoma (IMPC) is a rare variant of colorectal cancer with an adverse prognosis. "Retraction artifact" around tumor cells is a feature of IMPC. The aim of this study was to assess the nature of the retractions around the tumor cells and to describe the histopathological features of a group of 18 cases of IMPC.
  
  
  METHODS
  A pathology review of 128 consecutive colorectal cancers identified 18 cases of histologically proven IMPC using 5% of the total tumor volume comprised of a micropapillary component as the diagnostic criterion. Immunostains for D2-40, CD31, CD34, vascular endothelial growth factor A (VEGF-A), and mucin 1 (MUC-1) were performed using the avidin-biotin complex method.
  
  
  RESULTS
  Cases of IMPC were characterized by pseudomicropapillae surrounded by lacunar-like clear spaces. These structures exhibited the inside-out growth pattern as highlighted by MUC-1 staining. The lining of the lacunar spaces was immunoreactive to CD31 but not CD34 or D2-40, indicating that they are neovascular structures. Furthermore, the tumor cells strongly and diffusely expressed VEGF-A.
  
  
  CONCLUSIONS
  The strong coexpression of VEGF-A and CD31 suggests a prominent role of neoangiogenesis in these tumors.
authors.affiliation: Department of Anatomic Pathology, Moffitt Cancer Center, Tampa, FL 33612, USA. Domenico.Coppola@Moffitt.org.
authors.forename: Marilin
authors.initials: M
authors.lastname: Rosa
authors.forename: Maisoun
authors.initials: M
authors.lastname: Abdelbaqi
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Bui
authors.forename: Aejaz
authors.initials: A
authors.lastname: Nasir
authors.forename: Marilyn M
authors.initials: MM
authors.lastname: Bui
authors.forename: David
authors.initials: D
authors.lastname: Shibata
authors.forename: Domenico
authors.initials: D
authors.lastname: Coppola
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058846:Antibodies, Monoclonal, Murine-Derived / Q000096:biosynthesis; D018952:Antigens, CD34 / Q000096:biosynthesis; D000951:Antigens, Neoplasm / Q000096:biosynthesis; D014408:Biomarkers, Tumor; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000096:biosynthesis*; D009362:Neoplasm Metastasis; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis; D011379:Prognosis; D012189:Retrospective Studies; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis*
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D018952:Antigens, CD34; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D018396:Mucin-1; D019408:Platelet Endothelial Cell Adhesion Molecule-1; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C500987:monoclonal antibody D2-40