title: Assessment of tumor grade and angiogenesis in colorectal cancer: whole-volume perfusion CT.
abstract: OBJECTIVE
  The preoperative evaluation of tumor grading and angiogenesis has important clinical implications in the treatment and prognosis of patients with colorectal cancers (CRCs). The aim of the present study was to assess tumor perfusion with 256-slice computed tomography (CT) using whole-volume perfusion technology before surgery, and to investigate the differences in the perfusion parameters among tumor grades and the correlation between perfusion parameters and pathologic results in CRC.
  
  
  METHODS
  Thirty-seven patients with CRC confirmed by endoscopic pathology underwent whole-volume perfusion CT assessments with a 256-slice CT and surgery. Quantitative values for blood flow, blood volume, and time to peak were determined using commercial software. After surgery, resected specimens were analyzed immunohistochemically with CD105 antibodies for the quantification of microvessel density (MVD). The difference in CT perfusion parameters and MVD among different tumor differentiation grades was evaluated by the Student-Newman-Keuls test. The correlations between CT perfusion parameters and MVD were evaluated using the Pearson correlation analysis.
  
  
  RESULTS
  The mean blood flow was significantly different among well, moderately, and poorly differentiated groups (61.17 ± 17.97, 34.80 ± 13.06, and 22.24 ± 9.31 mL/minute/100 g, respectively; P < .05). The blood volume in the well-differentiated group was significantly higher than that in the moderately differentiated group (33.96 ± 24.81 vs. 16.93 ± 5.73 mL/100 g; P = .002) and that in the poorly differentiated group (33.96 ± 24.81 vs. 18.05 ± 6.01 mL/100 g; P = .009). The time to peak in the poorly differentiated group was significantly longer than that in the well-differentiated group (27.81 ± 11.95 vs. 17.60 ± 8.53 seconds; P = .016) and that in the moderately differentiated group (27.81 ± 11.95 vs. 18.94 ± 7.47 seconds; P = .028). There was no significant difference in the MVD among well, moderately, and poorly differentiated groups (33.47 ± 14.69, 28.89 ± 11.82, and 29.89 ± 11.02, respectively; P > .05). There was no significant correlation between CT perfusion parameters and MVD (r = 0.201, 0.295, and -0.178, respectively; P = .233, .076, and .292, respectively).
  
  
  CONCLUSIONS
  CT whole-volume perfusion technology has the potential to evaluate pathologic differentiation grade of CRC before surgery. However, preoperative perfusion CT parameters do not reflect the MVD of CRC.
authors.affiliation: Department of Radiology, China-Japan Friendship Hospital, No. 2 Yinghua East Street, Chaoyang District, Beijing 100029, China.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Radiology, China-Japan Friendship Hospital, No. 2 Yinghua East Street, Chaoyang District, Beijing 100029, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Pathology, China-Japan Friendship Hospital, Chaoyang District, Beijing 100029, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Radiology, China-Japan Friendship Hospital, No. 2 Yinghua East Street, Chaoyang District, Beijing 100029, China. Electronic address: cjr.wangwu@gmail.com.
authors.forename: Wu
authors.initials: W
authors.lastname: Wang
mesh_terms: D000230:Adenocarcinoma / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003106:Colon / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology; D015179:Colorectal Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007472:Iohexol / Q000031:analogs & derivatives; D008297:Male; D055806:Microvessels / Q000000981:diagnostic imaging; D008875:Middle Aged; D060787:Neoplasm Grading; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D011856:Radiographic Image Enhancement / Q000379:methods; D012007:Rectum / Q000098:blood supply / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide
keywords: CT; Colorectal cancer; angiogenesis; perfusion