title: In vivo assessment of neovascularization of liver metastases using perfusion CT.
abstract: Neovascularization of tumours produces a high microvessel density. Although diagnostic imaging is unable to visualize microvessels directly, it is possible to demonstrate associated changes in tissue perfusion. The aim of this study was to use the quantitative functional information and high spatial resolution of perfusion computed tomography to study neovascularization of hepatic metastases. Perfusion CT was performed in 13 patients with hepatic metastases from various primary tumours. Arterial perfusion was measured in the metastasis; both arterial and portal perfusion were measured in a small rim of liver tissue immediately adjacent to the metastasis. Perfusion measurements were correlated against survival of the patient in nine cases. Arterial perfusion was increased above normal values, both in the metastasis (median: 0.62 ml min-1 ml-1; range: 0.26-3.05 ml min-1 ml-1) and in the adjacent liver (median: 0.51 ml min-1 ml-1; range: 0.14-1.60 ml min-1 ml-1). Portal perfusion of adjacent liver was highly variable (median: 0.30 ml min-1 ml-1; range: 0.05-1.85 ml min-1 ml-1). Arterial perfusion was positively correlated with portal perfusion within liver tissue adjacent to metastases (p < 0.05, r = 0.58), a reversal of the normal situation. Survival of the patient correlated with arterial perfusion within the metastasis (p < 0.05, r = 0.69) but more closely with arterial perfusion in the adjacent liver (p < 0.02, r = 0.78). In conclusion, alterations in perfusion within metastases and adjacent liver are in accordance with the histological features of neovascularization. Perfusion CT offers a method for studying neovascularization in the living patient and offers prognostic information.
authors.affiliation: Centre for Functional Imaging, Wesley Research Institute, Auchenflower, Brisbane, Australia.
authors.forename: K A
authors.initials: KA
authors.lastname: Miles
authors.forename: D A
authors.initials: DA
authors.lastname: Leggett
authors.forename: B B
authors.initials: BB
authors.lastname: Kelley
authors.forename: M P
authors.initials: MP
authors.lastname: Hayball
authors.forename: R
authors.initials: R
authors.lastname: Sinnatamby
authors.forename: I
authors.initials: I
authors.lastname: Bunce
mesh_terms: D002277:Carcinoma / Q000098:blood supply* / Q000556:secondary*; D005500:Follow-Up Studies; D006801:Humans; D008099:Liver / Q000098:blood supply; D008113:Liver Neoplasms / Q000098:blood supply* / Q000556:secondary*; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed