title: Pancreatic endocrine tumors: tumor blood flow assessed with perfusion CT reflects angiogenesis and correlates with prognostic factors.
abstract: OBJECTIVE
  To prospectively correlate multidetector computed tomographic (CT) perfusion measurement of pancreatic endocrine tumors with tumor microvascular density (MVD) assessed by using histologic techniques and to determine whether perfusion CT parameters differ between tumor grades.
  
  
  METHODS
  Institutional review board approval and informed consent were obtained. Thirty-six patients (15 men, 21 women; mean age, 53 years; range, 18-78 years) with resectable pancreatic endocrine tumors underwent presurgical dynamic perfusion CT. Twenty-eight (78%) of 36 patients were included in the study group; eight were excluded because of artifacts that were not compatible with perfusion postprocessing. Multidetector CT perfusion data were analyzed to calculate tumor and normal pancreatic blood flow, blood volume, mean transit time, and permeability-surface area product. Multidetector CT perfusion parameters were compared with intratumoral MVD by using the Spearman correlation coefficient and with World Health Organization (WHO) classification, tumor size, tumor proliferation index, hormonal profile, and presence of metastases by using Mann-Whitney tests.
  
  
  RESULTS
  High correlation (r = 0.620, P < .001) was observed between tumor blood flow and intratumoral MVD. Blood flow was significantly higher (P = .02) in the group of benign tumors (WHO 1) than in the groups of tumors of indeterminate prognosis (WHO 2) or well-differentiated carcinomas (WHO 3). Blood flow was significantly higher in tumors with a proliferation index of 2% or less (P = .005) and in those without histologic signs of microscopic vascular involvement (P = .008). Mean transit time was longer in tumors with lymph node (P = .02) or liver (P = .05) metastasis.
  
  
  CONCLUSIONS
  Perfusion CT is feasible in patients with pancreatic endocrine tumors and reflects MVD. Perfusion CT measurements are correlated with histoprognostic factors, such as proliferation index and WHO classification.
authors.affiliation: Departments of Radiology and Pathology, INSERM Unité 773 CRB3, and the Fédération Médico Chirurgicale, Beaujon Hospital, 100 boulevard général Leclerc, 92110 Clichy La Garenne, France.
authors.forename: Gaspard
authors.initials: G
authors.lastname: d'Assignies
authors.forename: Anne
authors.initials: A
authors.lastname: Couvelard
authors.forename: Stéphane
authors.initials: S
authors.lastname: Bahrami
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Vullierme
authors.forename: Pascal
authors.initials: P
authors.lastname: Hammel
authors.forename: Olivia
authors.initials: O
authors.lastname: Hentic
authors.forename: Alain
authors.initials: A
authors.lastname: Sauvanet
authors.forename: Pierre
authors.initials: P
authors.lastname: Bedossa
authors.forename: Philippe
authors.initials: P
authors.lastname: Ruszniewski
authors.forename: Valérie
authors.initials: V
authors.lastname: Vilgrain
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging* / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000098:blood supply* / Q000000981:diagnostic imaging* / Q000473:pathology; D011379:Prognosis; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*