Solid malignancies have to develop their own blood supply for their aggressive growth and metastasis;a process known as tumor angiogenesis.Angiogenesis is largely involved in tumor survival,progression and spread,whic...Solid malignancies have to develop their own blood supply for their aggressive growth and metastasis;a process known as tumor angiogenesis.Angiogenesis is largely involved in tumor survival,progression and spread,which are known to be significantly attributed to treatment failures.Over the past decades,efforts have been made to understand the difference between nor-mal and tumor vessels.It has been demonstrated that tumor vasculature is structurally immature with chaotic and leaky phenotypes,which provides opportunities for developing novel anticancer strategies.Targeting tumor vasculature is not only a unique therapeutic interven-tion to starve neoplastic cells,but also enhances the efficacy of conventional cancer treatments.Vascular dis-rupting agents(VDAs) have been developed to disrupt the already existing neovasculature in actively growing tumors,cause catastrophic vascular shutdown within short time,and induce secondary tumor necrosis.VDAs are cytostatic;they can only inhibit tumor growth,but not eradicate the tumor.This novel drug mechanism has urged us to develop multiparametric imaging biomark-ers to monitor early hemodynamic alterations,cellular dysfunctions and metabolic impairments before tumor dimensional changes can be detected.In this article,we review the characteristics of tumor vessels,tubulin-destabilizing mechanisms of VDAs,and in vivo effects of the VDAs that have been mostly studied in preclinical studies and clinical trials.We also compare the differ-ent tumor models adopted in the preclinical studies on VDAs.Multiparametric imaging biomarkers,mainly diffu-sion-weighted imaging and dynamic contrast-enhanced imaging from magnetic resonance imaging,are evalu-ated for their potential as morphological and functional imaging biomarkers for monitoring therapeutic effects of VDAs.展开更多
Preoperative detection of lymph nodes（LNs） metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging（QDCE-MRI） in identifyi...Preoperative detection of lymph nodes（LNs） metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging（QDCE-MRI） in identifying LNs metastasis is not well understood. In the present study, 59 patients with histologically proven rectal carcinoma underwent preoperative QDCE-MRI. The short axis diameter ratio, long axis diameter ratio, short-to-long axis diameter ratio and QDEC-MRI parameters（Ktrans, Kep, fPV and Ve） values were compared between the non-metastatic（n=44） and metastatic（n=35） LNs groups based on pathological examination. Compared with the non-metastatic group, the metastatic group exhibited significantly higher short axis diameter（7.558±0.668 mm vs. 5.427±0.285 mm）, Ktrans（0.483±0.198 min-1 vs. 0.218±0.116 min^-1） and Ve（0.399±0.118 vs. 0.203±0.096） values（all P〈0.05）. The short-to-long axis diameter ratio, long axis diameter ratio, Kep and fPV values did not show significant differences between the two groups. In conclusion, our results showed that for LNs larger than 5 mm in rectal cancer, there are distinctive differences in the Ktrans and Ve values between the metastatic and non-metastatic LNs, suggesting that QDCE-MRI may be potentially helpful in identifying LNs status.展开更多
Perfusion magnetic resonance imaging (MRI) studies quantify the microcirculatory status of liver parenchyma and liver lesions, and can be used for the detection of liver metastases, assessing the effectiveness of anti...Perfusion magnetic resonance imaging (MRI) studies quantify the microcirculatory status of liver parenchyma and liver lesions, and can be used for the detection of liver metastases, assessing the effectiveness of antiangiogenic therapy, evaluating tumor viability after anticancer therapy or ablation, and diagnosis of liver cirrhosis and its severity. In this review, we discuss the basic concepts of perfusion MRI using tracer kinetic modeling, the common kinetic models applied for analyses, the MR scanning techniques, methods of data processing, and evidence that supports its use from published clinical and research studies. Technical standardization and further studies will help to establish and validate perfusion MRI as a clinical imaging modality.展开更多
基金Supported by(partially) The grants awarded by Fonds voor Wetenschappelijk Onderzoek-Vlaanderen(FWO Vlaanderen) Impulsfinanciering project(ZWAP/05/018)Geconcerteerde Onderzoeksactie of the Flemish Government,OT project(OT/06/70)+1 种基金the K.U.Leuven Molecular Small Animal Imaging Center MoSAIC (KUL EF/05/08)the center of excellence In vivo Molecular Imaging Research of K.U.Leuven and a EU project Asia-Link CfP 2006-EuropeAid/123738/C/ACT/Multi-Proposal No.128-498/111
文摘Solid malignancies have to develop their own blood supply for their aggressive growth and metastasis;a process known as tumor angiogenesis.Angiogenesis is largely involved in tumor survival,progression and spread,which are known to be significantly attributed to treatment failures.Over the past decades,efforts have been made to understand the difference between nor-mal and tumor vessels.It has been demonstrated that tumor vasculature is structurally immature with chaotic and leaky phenotypes,which provides opportunities for developing novel anticancer strategies.Targeting tumor vasculature is not only a unique therapeutic interven-tion to starve neoplastic cells,but also enhances the efficacy of conventional cancer treatments.Vascular dis-rupting agents(VDAs) have been developed to disrupt the already existing neovasculature in actively growing tumors,cause catastrophic vascular shutdown within short time,and induce secondary tumor necrosis.VDAs are cytostatic;they can only inhibit tumor growth,but not eradicate the tumor.This novel drug mechanism has urged us to develop multiparametric imaging biomark-ers to monitor early hemodynamic alterations,cellular dysfunctions and metabolic impairments before tumor dimensional changes can be detected.In this article,we review the characteristics of tumor vessels,tubulin-destabilizing mechanisms of VDAs,and in vivo effects of the VDAs that have been mostly studied in preclinical studies and clinical trials.We also compare the differ-ent tumor models adopted in the preclinical studies on VDAs.Multiparametric imaging biomarkers,mainly diffu-sion-weighted imaging and dynamic contrast-enhanced imaging from magnetic resonance imaging,are evalu-ated for their potential as morphological and functional imaging biomarkers for monitoring therapeutic effects of VDAs.
基金supported by the Provincial Key Clinical Specialty(Medical Imaging)Development Program from Health and Family Planning Commission of Hunan Province,China(No.2015/43)the Health and Family Planning Commission of Hunan Province,China(No.B2016060)the National Key Clinical Specialty(Oncology Department)Development Program from National Health and Family Planning Commission of China(No.2013/544)
文摘Preoperative detection of lymph nodes（LNs） metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging（QDCE-MRI） in identifying LNs metastasis is not well understood. In the present study, 59 patients with histologically proven rectal carcinoma underwent preoperative QDCE-MRI. The short axis diameter ratio, long axis diameter ratio, short-to-long axis diameter ratio and QDEC-MRI parameters（Ktrans, Kep, fPV and Ve） values were compared between the non-metastatic（n=44） and metastatic（n=35） LNs groups based on pathological examination. Compared with the non-metastatic group, the metastatic group exhibited significantly higher short axis diameter（7.558±0.668 mm vs. 5.427±0.285 mm）, Ktrans（0.483±0.198 min-1 vs. 0.218±0.116 min^-1） and Ve（0.399±0.118 vs. 0.203±0.096） values（all P〈0.05）. The short-to-long axis diameter ratio, long axis diameter ratio, Kep and fPV values did not show significant differences between the two groups. In conclusion, our results showed that for LNs larger than 5 mm in rectal cancer, there are distinctive differences in the Ktrans and Ve values between the metastatic and non-metastatic LNs, suggesting that QDCE-MRI may be potentially helpful in identifying LNs status.
基金Supported by Singapore Cancer Syndicate (SCS_CS-0072)Biomedical Research Council (BMRC 08/1/31/19/577)+1 种基金CRUK and EPSRC Cancer Imaging Centre in association with the MRC and Department of Health (England) grant C1060/A10334NHS funding to the NIHR
文摘Perfusion magnetic resonance imaging (MRI) studies quantify the microcirculatory status of liver parenchyma and liver lesions, and can be used for the detection of liver metastases, assessing the effectiveness of antiangiogenic therapy, evaluating tumor viability after anticancer therapy or ablation, and diagnosis of liver cirrhosis and its severity. In this review, we discuss the basic concepts of perfusion MRI using tracer kinetic modeling, the common kinetic models applied for analyses, the MR scanning techniques, methods of data processing, and evidence that supports its use from published clinical and research studies. Technical standardization and further studies will help to establish and validate perfusion MRI as a clinical imaging modality.
