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1.
Eur Radiol ; 23(12): 3336-44, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23979104

ABSTRACT

OBJECTIVE: To explore whether pre-reoperative dynamic contrast-enhanced (DCE)-MRI findings correlate with clinical outcome in patients who undergo surgical treatment for recurrent rectal carcinoma. METHODS: A retrospective study of DCE-MRI in patients with recurrent rectal cancer was performed after obtaining an IRB waiver. We queried our PACS from 1998 to 2012 for examinations performed for recurrent disease. Two radiologists in consensus outlined tumour regions of interest on perfusion images. We explored the correlation between K(trans), Kep, Ve, AUC90 and AUC180 with time to re-recurrence of tumour, overall survival and resection margin status. Univariate Cox PH models were used for survival, while univariate logistic regression was used for margin status. RESULTS: Among 58 patients with pre-treatment DCE-MRI who underwent resection, 36 went directly to surgery and 18 had positive margins. K(trans) (0.55, P = 0.012) and Kep (0.93, P = 0.04) were inversely correlated with positive margins. No significant correlations were noted between K(trans), Kep, Ve, AUC90 and AUC180 and overall survival or time to re-recurrence of tumour. CONCLUSION: K(trans) and Kep were significantly associated with clear resection margins; however overall survival and time to re-recurrence were not predicted. Such information might be helpful for treatment individualisation and deserves further investigation.


Subject(s)
Image Enhancement/methods , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/surgery , Rectal Neoplasms/diagnosis , Rectal Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Chemoradiotherapy , Contrast Media , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Neoadjuvant Therapy , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Preoperative Care , Prognosis , Proportional Hazards Models , Rectal Neoplasms/mortality , Rectal Neoplasms/pathology , Reoperation , Retrospective Studies , Survival Rate , Treatment Outcome
3.
J Nanosci Nanotechnol ; 12(12): 9058-66, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23447958

ABSTRACT

In this study, tin/tinoxide/multi oxide/multi walled carbon nano tube (Sn/SnO2/MWCNT) composites were produced by thermal evaporation and then subsequent plasma oxidation. Buckypapers having controlled porosity were prepared by vacuum filtration from functionalized MWCNTs. Pure metallic tin was thermally evaporated on the buckypapers in argon atmosphere with different thicknesses. It was determined that the evaporated pure tin nano crystals were mechanically penetrated into pores of buckypaper to form a nanocomposite. The tin/MWCNT composites were subjected to plasma oxidation process at oxygen/argon gas mixture. Three different plasma oxidation times (30, 45 and 60 minutes) were used to investigate oxidation and physical and microstructural properties. The effect of coating thickness and oxidation time was investigated to understand the effect of process parameters on the Sn and SnO2 phases after plasma oxidation. Quantitative phase analysis was performed in order to determine the relative phase amounts. The structural properties were studied by field-emission gun scanning electron microscopy (FEG-SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD).

4.
Eur Radiol ; 22(4): 821-31, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22101743

ABSTRACT

OBJECTIVE: To determine the ability of dynamic contrast enhanced (DCE-MRI) to predict pathological complete response (pCR) after preoperative chemotherapy for rectal cancer. METHODS: In a prospective clinical trial, 23/34 enrolled patients underwent pre- and post-treatment DCE-MRI performed at 1.5T. Gadolinium 0.1 mmol/kg was injected at a rate of 2 mL/s. Using a two-compartmental model of vascular space and extravascular extracellular space, K(trans), k(ep), v(e), AUC90, and AUC180 were calculated. Surgical specimens were the gold standard. Baseline, post-treatment and changes in these quantities were compared with clinico-pathological outcomes. For quantitative variable comparison, Spearman's Rank correlation was used. For categorical variable comparison, the Kruskal-Wallis test was used. P ≤ 0.05 was considered significant. RESULTS: Percentage of histological tumour response ranged from 10 to 100%. Six patients showed pCR. Post chemotherapy K(trans) (mean 0.5 min(-1) vs. 0.2 min(-1), P = 0.04) differed significantly between non-pCR and pCR outcomes, respectively and also correlated with percent tumour response and pathological size. Post-treatment residual abnormal soft tissue noted in some cases of pCR prevented an MR impression of complete response based on morphology alone. CONCLUSION: After neoadjuvant chemotherapy in rectal cancer, MR perfusional characteristics have been identified that can aid in the distinction between incomplete response and pCR. KEY POINTS: Dynamic contrast enhanced (DCE) MRI provides perfusion characteristics of tumours. These objective quantitative measures may be more helpful than subjective imaging alone Some parameters differed markedly between completely responding and incompletely responding rectal cancers. Thus DCE-MRI can potentially offer treatment-altering imaging biomarkers.


Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Gadolinium DTPA , Image Enhancement/methods , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Magnetic Resonance Imaging/methods , Adult , Aged , Bevacizumab , Contrast Media , Female , Fluorouracil/administration & dosage , Humans , Leucovorin/administration & dosage , Male , Middle Aged , Neoadjuvant Therapy/methods , Organoplatinum Compounds/administration & dosage , Prognosis , Reproducibility of Results , Sensitivity and Specificity , Treatment Outcome
5.
Ann Oncol ; 20(9): 1589-1595, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19491285

ABSTRACT

BACKGROUND: This study reports the results of hepatic arterial infusion (HAI) with floxuridine (FUDR) and dexamethasone (dex) in patients with unresectable intrahepatic cholangiocarcinoma (ICC) or hepatocellular carcinoma (HCC) and investigates dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) assessment of tumor vascularity as a biomarker of outcome. PATIENTS AND METHODS: Thirty-four unresectable patients (26 ICC and eight HCC) were treated with HAI FUDR/dex. Radiologic dynamic and pharmacokinetic parameters related to tumor perfusion were analyzed and correlated with response and survival. RESULTS: Partial responses were seen in 16 patients (47.1%); time to progression and response duration were 7.4 and 11.9 months, respectively. Median follow-up and median survival were 35 and 29.5 months, respectively; 2-year survival was 67%. DCE-MRI data showed that patients with pretreatment integrated area under the concentration curve of gadolinium contrast over 180 s (AUC 180) >34.2 mM.s had a longer median survival than those with AUC 180 <34 mM.s (35.1 versus 19.1 months, P = 0.002). Decreased volume transfer exchange between the vascular space and extracellular extravascular space (-DeltaK(trans)) and the corresponding rate constant (-Deltak(ep)) on the first post-treatment scan both predicted survival. CONCLUSIONS: In patients with unresectable primary liver cancer, HAI therapy can be effective and safe. Pretreatment and early post-treatment changes in tumor perfusion characteristics may predict treatment outcome.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chemotherapy, Cancer, Regional Perfusion , Liver Neoplasms/drug therapy , Liver Neoplasms/mortality , Magnetic Resonance Imaging/methods , Adult , Aged , Aged, 80 and over , Area Under Curve , Bile Duct Neoplasms/drug therapy , Bile Ducts, Intrahepatic/pathology , Carcinoma, Hepatocellular/drug therapy , Cholangiocarcinoma/drug therapy , Dexamethasone/administration & dosage , Disease-Free Survival , Female , Floxuridine/administration & dosage , Humans , Male , Middle Aged , Survival Analysis , Treatment Outcome
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