Viable Tumor Tissue Research Articles

Abstract B67: In silico study of drug active transport via macrophages in tumor chemotherapy

Abstract This work focuses on the study of active transport of nanoparticles loaded with drug in cancer chemotherapy to achieve a more homogeneous distribution of chemotherapeutics in the tumor inner regions. These regions are known for insufficient functional lymphatic vessels as well as blood vessels with enhanced permeability contributing to near zero interstitial fluid velocity. Moreover, due to the hypertension caused by elevated interstitial pressure in the tumor inner regions and the functional lymphatic vessels near the exterior margin of the tumor, the interstitial fluid velocity directs towards the outside of the tumor. On the other hand, the effective diffusion distance of nanoparticles may be decreased by binding with the extracellular matrix. As a result, the delivery of nanoparticles by convection and diffusion is hindered. However, it is known that inner tumor regions have lower oxygen levels compared to the tissues near the vasculature. Current experimental research is focusing on the idea to deliver nanoparticles by conjugating them to macrophages, which are known to heavily infiltrate tumor hypoxic regions. This may achieve higher drug concentrations since macrophages can travel into tumor inner regions by chemotaxis. We launched our in silico experiment on a two-dimensional 4 mm square area of tissue incorporating a tumor angiogenesis model describing the distribution of vessel permeability and radius, blood flow rate, and hematocrit levels along the vessel system. The model calculates the corresponding oxygen levels, extracellular matrix density, interstitial pressure and tumor cell pressure fields by simulating viable and necrotic tumor tissue, diffusion of small molecules (cell nutrients, oxygen, and drug), and conservation of mass. Mass conservation equations describe growth (proliferation as a function of total cycling cells) and death from drug cytotoxicity (apoptosis as a function of cell sensitivity and cycling cells). These are combined with diffusion of small molecules to a reaction-diffusion equation. Rate constants for proliferation and apoptosis are modified by functions that represent their dependence on cell nutrients and oxygen (proliferation) and drug concentration (death), along with a dependence on spatial diffusion of these substances. We fully simulate the extravasation of macrophages from the vasculature into the tissue, the movement of macrophages competing with the interstitial fluid velocity, the release of nanoparticles into the tissue, and the effect on tumor apoptosis. The macrophages-particle treatment protects the nanoparticles from binding to the extracellular matrix and is thus able to overcome the biophysical barriers in traditional nanoparticle delivery, with the macrophages moving into the tumor with elevated cell mobility. At the start, we observe that the macrophages form a ring around the tumor margin by balancing the interstitial pressure and oxygen gradients. Inside the tumor, the macrophages are more likely to cluster in the hypoxic region. However, tumor apoptosis due to the nanomedicine may lead to drastic changes in tumor size and oxygen levels, as well as an elevation of the interstitial pressure gradient which may convect the macrophages away from the tumor boundary (active region) or push the macrophages away from the hypoxic / necrotic area before fully unloading the drug. This finding predicts a physical resistance to the treatment. We conclude that to reduce the potential resistance of macrophage-nanoparticle treatments, the strength of the nanomedicine needs to be in an optimal range to shrink the tumor while maintaining a steady environment for the macrophages lodged in the hypoxic regions. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the Second AACR International Conference on Frontiers in Basic Cancer Research; 2011 Sep 14-18; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2011;71(18 Suppl):Abstract nr B67.

Influence of the vascular damaging agents DMXAA and ZD6126 on hypericin distribution and accumulation in RIF-1 tumors

We investigated the influence of two types of vascular damaging agents (VDAs) (DMXAA vs. ZD6126) and sequence of administration (VDA 24 h before HYP vs. HYP 1 h before VDA) to evaluate the effect on hypericin (HYP) accumulation and distribution in necrotic tumors. Frozen sections of dorsally inoculated RIF-1 tumors were analyzed by fluorescence microscopy and H&E stained for histological evaluation. The localization of HYP was assessed both qualitatively and semi-quantitatively in necrotic tumor, viable tumor, or nontarget host tissue. Whereas the type of VDA did not influence HYP accumulation and distribution, a clear advantage could be seen when administering VDA 24 h before HYP compared to HYP 1 h before VDA, pointing toward the absence of a "trapping" mechanism. In DMXAA-treated and not in ZD6126-treated tumors, spotty fluorescence was observed which is likely to be a consequence of neutrophil phagocytosis. Dexamethasone treatment neither did influence this phenomenon nor did change HYP uptake in necrotic tumor. We conclude that HYP accumulation is optimal when it is administered after VDA injection. We also found that HYP accumulation in necrosis is not changed when using VDAs with different working mechanisms. This insight provides a rationale for tumor necrosis therapy (TNT) using iodine-131-labeled hypericin ([(131)I]-HYP) in combination with VDAs.

Quantitative dual energy CT measurements in rabbit VX2 liver tumors: Comparison to perfusion CT measurements and histopathological findings

PurposeTo evaluate the correlation between quantitative dual energy CT and perfusion CT measurements in rabbit VX2 liver tumors. Materials and methodsThis study was approved by the institutional animal care and use committee at our institution. Nine rabbits with VX2 liver tumors underwent contrast-enhanced dual energy CT and perfusion CT. CT attenuation for the tumors and normal liver parenchyma and tumor-to-liver ratio were obtained at the 140kVp, 80kVp, average weighted images and dual energy CT iodine maps. Quantitative parameters for the viable tumor and adjacent liver were measured with perfusion CT. The correlation between the enhancement values of the tumor in iodine maps and perfusion CT parameters of each tumor was analyzed. Radiation dose from dual energy CT and perfusion CT was measured. ResultsEnhancement values for the tumor were higher than that for normal liver parenchyma at the hepatic arterial phase (P<0.05). The highest tumor-to-liver ratio was obtained in hepatic arterial phase iodine map. Hepatic blood flow of the tumor was higher than that for adjacent liver (P<0.05). Enhancement values of hepatic tumors in the iodine maps positively correlated with permeability of capillary vessel surface (r=0.913, P<0.001), hepatic blood flow (r=0.512, P=0.010), and hepatic blood volume (r=0.464, P=0.022) at the hepatic arterial phases. The effective radiation dose from perfusion CT was higher than that from DECT (P<0.001). ConclusionsThe enhancement values for viable tumor tissues measured in iodine maps were well correlated to perfusion CT measurements in rabbit VX2 liver tumors. Compared with perfusion CT, dual energy CT of the liver required a lower radiation dose.

Experience of fluoroscopy-aided thoracoscopic resection of pulmonary nodule localised with Lipiodol in a child

We report the case of a 12-year-old boy with a huge liver tumour 20 cm in diameter with multiple lung metastases. Six months after systemic chemotherapy was initiated, all tumours had disappeared with the exception of the liver tumour and a tiny lung tumour 2.5 mm in diameter. Fluoroscopy-assisted thoracoscopic resection of the pulmonary nodule was performed to evaluate whether viable tumour tissue remained in the lung lesion. Before moving the patient to the operating room, the nodule was marked by Lipiodol under CT fluoroscopic guidance with the patient under local anaesthesia. This procedure allowed correct visualisation of the area that should be resected.

Molecular imaging of gliomas with PET: Opportunities and limitations

Neuroimaging enables the noninvasive evaluation of glioma and is considered to be one of the key factors for individualized therapy and patient management, since accurate diagnosis and demarcation of viable tumor tissue is required for treatment planning as well as assessment of treatment response. Conventional imaging techniques like MRI and CT reveal morphological information but are of limited value for the assessment of more specific and reproducible information about biology and activity of the tumor. Molecular imaging with PET is increasingly implemented in neuro-oncology, since it provides additional metabolic information of the tumor, both for patient management as well as for evaluation of newly developed therapeutics. Different molecular processes have been proposed to be useful, like glucose consumption, expression of amino acid transporters, proliferation rate, membrane biosynthesis, and hypoxia. Thus, PET might help neuro-oncologists gain further insights into tumor biology by "true molecular imaging" as well as understand treatment-related phenomena. This review describes the method of PET acquisition as well as the tracers used to image biological processes in gliomas. Furthermore, it considers the clinical impact of PET on the use of currently available radiotracers, which were shown to be potentially valuable for discrimination between neoplastic and nonneoplastic tissue, as well as on tumor grading, determinination of treatment response, and providing an outlook toward further developments.

Diagnostic implications of histological analysis of neurosurgical aspirate in addition to routine resections

Many neurosurgical centers use surgical aspirators to remove brain tumor tissue. The resulting aspirate consists of fragmented viable tumor, normal or tumor-infiltrated brain tissue as well as necrotic tissue, depending on the type of tumor. Typically, such fragmented aspirate material is collected but discarded and not included when making the histopathological diagnosis. Whereas the general suitability of surgical aspirate for histological diagnosis and immunohistochemical staining has been reported previously, we have systematically investigated whether the collection and histological examination of surgical aspirate has an impact on diagnosis, in particular on the tumor grading, by providing additional features. Surgical and aspirate specimens from 85 consecutive neurosurgical procedures were collected and routinely processed. Sixty-five of the 85 specimens were intrinsic brain tumors and the remainder consisted of metastatic tumors, meningiomas, schwannomas and lymphomas. Important diagnostic features seen in surgical aspirate were microvascular proliferation (n = 3), more representative necrosis (n = 2), and gemistocytic component (n = 2). In one case, microvasular proliferations were seen in the aspirate only, leading to a change of diagnosis. Collection of surgical aspirate also generates additional archival material which can be microdissected and used for tissue microarrays or for molecular studies.

Characterization of Bone Metastases from Rapid Autopsies of Prostate Cancer Patients

Bone is the most common metastatic site for prostate cancer, and osseous metastases are the leading cause of morbidity from this disease. Recent autopsy studies prove that 100% of men who die of prostate cancer have bone involvement. Understanding the biology of prostate cancer and its evolution to an incurable androgen-independent phenotype requires an understanding of the genetic and cellular alterations that lead to the seeding and proliferation of tumor foci in bone, as well as the microenvironment in which these metastases arise. No intensive studies, however, have been conducted on osseous metastatic tissues from patients with metastatic prostate cancer due to lack of access to such tissues for profiling and other research. We show, for the first time, a reproducible methodology to obtain high quality clinical tumor tissues metastatic to the bone. This technique allowed the procurement of viable metastatic tumor tissue from involved bones in 13 recent autopsies conducted at the University of Michigan and analyzed the gene expression of these tissues using real-time PCR and microarrays. We present here the discovery of nonossified bone metastases from multiple patients with advanced prostate cancer and their subsequent characterization and comparison to nonosseous metastases from the same patients. This represents a versatile and practical approach that may be employed to characterize the steps in metastasis and the phenotypic characteristics of osseous metastasis of prostate cancer and to profile RNA, DNA, and cDNA from tumor samples metastatic to the bone.

Viable Tumor Tissue Adherent to Needle Applicators after Local Ablation: A Risk Factor for Local Tumor Progression

BackgroundLocal tumor progression (LTP) is a serious complication after local ablation of malignant liver tumors, negatively influencing patient survival. LTP may be the result of incomplete ablation of the treated tumor. In this study, we determined whether viable tumor cells attached to the needle applicator after ablation was associated with LTP and disease-free survival.MethodsIn this prospective study, tissue was collected of 96 consecutive patients who underwent local liver ablations for 130 liver malignancies. Cells and tissue attached to the needle applicators were analyzed for viability using glucose-6-phosphate-dehydrogenase staining and autofluorescence intensity levels of H&E stained sections. Patients were followed-up until disease progression.ResultsViable tumor cells were found on the needle applicators after local ablation in 26.7% of patients. The type of needle applicator used, an open approach, and the omission of track ablation were significantly correlated with viable tumor tissue adherent to the needle applicator. The presence of viable cells was an independent predictor of LTP. The attachment of viable cells to the needle applicators was associated with a shorter time to LTP.ConclusionsViable tumor cells adherent to the needle applicators were found after ablation of 26.7% of patients. An independent risk factor for viable cells adherent to the needle applicators is the omission of track ablation. We recommend using only RFA devices that have track ablation functionality. Adherence of viable tumor cells to the needle applicator after local ablation was an independent risk factor for LTP.

The potential use of 2-[18F]fluoro-2-deoxy-D-galactose as a PET/CT tracer for detection of hepatocellular carcinoma

The aim of the study was to evaluate the feasibility of using the hepatocyte-specific positron emission tomography (PET) tracer 2-[(18)F]fluoro-2-deoxy-D-galactose (FDGal) as a tracer for hepatocellular carcinoma (HCC). In addition to standard clinical investigations, 39 patients with known HCC or suspected of having HCC underwent a partial-body FDGal PET/CT (from base of skull to mid-thigh). Diagnosis of HCC was based on internationally approved criteria. FDGal PET/CT images were analysed for areas with high (hot spots) or low (cold spots) tracer accumulation when compared to surrounding tissue. Seven patients did not have HCC and FDGal PET/CT was negative in each of them. Twenty-three patients had HCC and were included before treatment. FDGal PET/CT correctly identified 22 of these patients, which was comparable to contrast-enhanced CT. Interestingly, FDGal PET/CT was conclusive in 12 patients in whom conventional imaging techniques were inconclusive and required additional diagnostic investigations or close follow-up. Nine patients were included after treatment of HCC and in these patients FDGal PET/CT was able to distinguish between viable tumour tissue as hot spots and areas with low metabolic activity as cold spots. FDGal PET/CT detected extrahepatic disease in nine patients which was a novel finding in eight patients. FDGal PET/CT has great clinical potential as a PET tracer for detection of extra- but also intrahepatic HCC. In the present study, the specificity of FDGal PET/CT was 100%, which is very promising but needs to be confirmed in a larger, prospective study.

Abstract 5398: A primer dose followed by low-bolus dose schedule for safe and efficacious bacterial tumor targeting with S. typhimurium A1-R

Abstract We have previously developed a bacterial cancer therapy strategy by targeting viable tumor tissue with Salmonella typhimurium containing two auxotrophic mutations. These auxotrophs grow in viable as well as necrotic areas of tumors. However, the auxotrophy severely restricts growth of these bacteria in normal tissue, making this a relative safe treatment. The S. typhimurium A1-R mutant, which is auxotrophic for leu-arg, and selected for high antitumor virulence, has been shown to be effective as monotherapy against human prostate, breast, pancreatic, and fibrosarcoma tumors that have been orthotopically implanted in nude mice. In the present study, we developed a strategy to maximize efficacy and minimize toxicity for bacterial tumor treatment. A small dose of S. typhimurium A1-R bacteria was first administered to tumor-bearing animals (the primer dose) as pre-treatment followed by a high dose (106 i.v.) 4 hours later. Compared with very high dose bacteria treatment (5 × 106 per mouse), the primer dose strategy had no observable side effects. The very high dose had toxicity in immunocompetent mice. The primer dose may induce cytokines in the mouse necessary for invasion of the tumor by the bacteria allowing a relatively small subsequent dose to be effective and safe. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5398. doi:10.1158/1538-7445.AM2011-5398

Parametric images via dynamic 18F-fluorodeoxyglucose positron emission tomographic data acquisition in predicting midterm outcome of liver metastases secondary to gastrointestinal stromal tumours

(18)F-Fluorodeoxyglucose positron emission tomography (FDG PET) may underestimate viable tumour tissue in patients with gastrointestinal stromal tumours (GIST) treated with molecular targeted agents. The aim of the present study was to investigate the value of parametric images generated after dynamic data acquisition for the detection of active liver metastases. The analysis included 65 dynamic FDG PET studies in 34 patients with liver metastases from GIST who were treated with imatinib or sunitinib. Parametric images of intercept and slope were calculated by dedicated software using a voxel-based linear regression of time-activity data. Intercept images represent the tracer's distribution volume and the slope its overall metabolic turnover. All images were assessed visually and semi-quantitatively. Liver disease status was established 12 months after each PET study. Dichotomous variables of visual interpretation and various quantitative parameters were entered in a statistical model of linear discriminant analysis. Visual analysis of slope images was more sensitive than the standard 1-h FDG uptake evaluation (70.6 vs 51.0%, p = 0.016) in detecting cases with liver disease progression (n = 51). Specificity did not differ. Combination of all variables in the discriminant analysis model correctly classified 87.7% of cases as progressive or non-progressive disease. Sensitivity was raised to 88.2%. Parametric images of intercept and slope add a new dimension to the interpretation of FDG PET studies, by isolating visually and quantifying the perfusion and phosphorylation-dependent part of tracer uptake. In treated GIST patients, integration of this information with the 1-h uptake data achieves better characterization of hepatic lesions with respect to disease activity.

Vessel imaging with viable tumor analysis for quantification of tumor angiogenesis

Imaging of tumor microvasculature has become an important tool for studying angiogenesis and monitoring antiangiogenic therapies. Ultrasmall paramagnetic iron oxide contrast agents for indirect imaging of vasculature offer a method for quantitative measurements of vascular biomarkers such as vessel size index, blood volume, and vessel density (Q). Here, this technique is validated with direct comparisons to ex vivo micro-computed tomography angiography and histologic vessel measurements, showing significant correlations between in vivo vascular MRI measurements and ex vivo structural vessel measurements. The sensitivity of the MRI vascular parameters is also demonstrated, in combination with a multispectral analysis technique for segmenting tumor tissue to restrict the analysis to viable tumor tissue and exclude regions of necrosis. It is shown that this viable tumor segmentation increases sensitivity for detection of significant effects on blood volume and Q by two antiangiogenic therapeutics [anti-vascular endothelial growth factor (anti-VEGF) and anti-neuropilin-1] on an HM7 colorectal tumor model. Anti-vascular endothelial growth factor reduced blood volume by 36±3% (p<0.0001) and Q by 52±3% (p<0.0001) at 48 h post-treatment; the effects of anti-neuropilin-1 were roughly half as strong with a reduction in blood volume of 18±6% (p<0.05) and a reduction in Q of 33±5% (p<0.05) at 48 h post-treatment.

Current molecular imaging of spinal tumors in clinical practice.

Energy metabolism measurements in spinal cord tumors, as well as in osseous spinal tumors/metastasis in vivo, are rarely performed only with molecular imaging (MI) by positron emission tomography (PET). This imaging modality developed from a small number of basic clinical science investigations followed by subsequent work that influenced and enhanced the research of others. Apart from precise anatomical localization by coregistration of morphological imaging and quantification, the most intriguing advantage of this imaging is the opportunity to investigate the time course (dynamics) of disease-specific molecular events in the intact organism. Most importantly, MI represents one of the key technologies in translational molecular neuroscience research, helping to develop experimental protocols that may later be applied to human patients. PET may help monitor a patient at the vertebral level after surgery and during adjuvant treatment for recurrent or progressive disease. Common clinical indications for MI of primary or secondary CNS spinal tumors are: (i) tumor diagnosis, (ii) identification of the metabolically active tumor compartments (differentiation of viable tumor tissue from necrosis) and (iii) prediction of treatment response by measurement of tumor perfusion or ischemia. While spinal PET has been used under specific circumstances, a question remains as to whether the magnitude of biochemical alterations observed by MI in CNS tumors in general (specifically spinal tumors) can reveal any prognostic value with respect to survival. MI may be able to better identify early disease and to differentiate benign from malignant lesions than more traditional methods. Moreover, an adequate identification of treatment effectiveness may influence patient management. MI probes could be developed to image the function of targets without disturbing them or as treatment to modify the target's function. MI therefore closes the gap between in vitro and in vivo integrative biology of disease. At the spinal level, MI may help to detect progression or recurrence of metastatic disease after surgical treatment. In cases of nonsurgical treatments such as chemo-, hormone- or radiotherapy, it may better assess biological efficiency than conventional imaging modalities coupled with blood tumor markers. In fact, PET provides a unique possibility to correlate topography and specific metabolic activity, but it requires additional clinical and experimental experience and research to find new indications for primary or secondary spinal tumors.

Improving the Yield of Histological Sampling in Patients With Suspected Colorectal Cancer During Colonoscopy by Introducing a Colonoscopy Quality Assurance Program.

BackgroundMasses discovered by clinical examination, imaging or endoscopic studies that are suspicious for malignancy typically require biopsy confirmation before treatment is initiated. Biopsy specimens may fail to yield a definitive diagnosis if the lesion is extensively ulcerated or otherwise necrotic and viable tumor tissue is not obtained on sampling. The diagnostic yield is improved when multiple biopsy samples (BSs) are taken. A colonoscopy quality-assurance program (CQAP) was instituted in 2003 in our institution. The aim of this study was to determine the effect of instituting a CQAP on the yield of histological sampling in patients with suspected colorectal cancer (CRC) during colonoscopy.MethodInitial assessment of colonoscopy practice was performed in 2003. A total of five patients with suspected CRC during colonoscopy were documented in 2003. BSs confirmed CRC in three (60%) patients and were nondiagnostic in two (40%). A quality-improvement process was instituted which required a minimum six BSs with adequate size of the samples from any suspected CRC during colonoscopy. A total of 37 patients for the period 2004-2010 were prospectively assessed.ResultsThe diagnosis of CRC was confirmed with histological examination of BSs obtained during colonoscopy in 63% of patients in 2004, 60% in 2005, 50% in 2006, 67% in 2007, 100% in 2008, 67% in 2009 and 100% in 2010. The yield of histological sampling increased significantly (p<0.02) from 61% in 2004-2007 to 92% in 2008-2010.ConclusionThe implementation of a quality assurance and improvement program increased the yield of histological sampling in patients with suspected CRC during colonoscopy.

Enhanced Ablation of High Intensity Focused Ultrasound with Microbubbles: An Experimental Study on Rabbit Hepatic VX2 Tumors

This study was designed to assess the enhanced effect of high intensity focused ultrasound (HIFU) ablation with microbubbles on rabbit hepatic VX2 tumors and to compare the detection sensitivity of CEUS and CECT to determine the residual viable tissue after ablation of HIFU. Forty rabbits with hepatic VX2 tumors were randomly separated into two groups (20 animals per group) before HIFU ablation. A bolus of 0.2mL of saline or a microbubble-based ultrasound (US) contrast agent was injected intravenously to group I rabbits and group II rabbits, respectively. The HIFU ablation procedure was started 15s after the injection. Tumors were examined with grayscale contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed tomography (CECT) immediately before and after HIFU ablation. Histopathologic assessment was performed immediately after treatment imaging. Before ablation, intense contrast enhancement during arterial phase was observed at the whole tumors or the periphery of the tumors by CEUS and CECT. Lower HIFU energy was used in group II than in group I (P<0.001). Histopathologic assessment revealed local residual viable tumor tissues due to incomplete ablation in 47.4% (9/19) of tumors in group I and 10% (2/20) of tumors in group II (P<0.05). The concordance rate of CEUS (90.9%) with histopathology on residual tumor detection was higher than that of CECT (27.3%, P<0.05). Introduction of the microbubble agent enhances HIFU therapeutic efficacy. CEUS proves to have high sensitivity in assessment of residual viable rabbit VX2 tumor after HIFU.

R-CHOEP-14 × 6 Followed by Systemic CNS Prophylaxis for Diffuse Large B-Cell Lymphoma/Follicular Lymphoma Grade 3 with Age Adjusted IPI Score 2–3: Final Results of a Nordic Lymphoma Group Phase 2 Study Including 156 Patients Aged 18–65 Years.

AbstractAbstract 2805CHOP – based chemotherapy for aggressive lymphomas in patients with age-adjusted International Prognostic Index (IPI) score of 2–3 resulted in a historical 3-year progression free survival of approximately 30% in a previous Nordic phase III study. The aim of the present study is to determine whether an intensified regimen with chemoimmunotherapy and CNS prophylaxis improves outcome. Methods:From October 2004 to June 2008 patients were included in a phase II study. Inclusion criteria: 1) Age 18–65 years. 2) Newly diagnosed de novo diffuse large B-cell lymphoma (DLBCL) or follicular lymphoma (FL) grade III. 3) No clinical sign of CNS disease and negative CSF cytology/flow cytometry by lumbar puncture. 4) No HIV infection. 5) WHO performance score 0–3. 6) Adequate organ functions. Schedule: Six courses of R-CHOEP14. Pegfilgrastim 6 mg sc. day four of each cycle. One course of high dose cytarabine 12 g/m2 (6 g/m2 for patients 60–65 years). One course of high dose methtrexate 3 g/m2 (1 g/m2 for patients 60–65 years). Biopsy and/or 18FDG PET/CT imaging of residual masses after fulfilled therapy was recommended, but not mandatory. Radiotherapy was given to residual masses of uncertain significance. Results.Demographic data:.156 eligible patients were included (97 males). Median age: 54 years (range 20–64). Histology: DLBCL: 145, FL grade 3: 12 (three patients no data). Age adjusted IPI score: 2: 117; 3: 39. Stage III-IV: 150 patients. LDH elevated: 151 patients. Performance status 2–3: 51 patients. B-symptoms were registered in 97 patients, more than one extranodal site in 42 and bulky lesions (≥ 10 cm) in 68. Median observation time for patients alive at last follow up was 36 months. Toxicity: Three toxic deaths are registered, one large bowel perforation, one fulminant hepatic necrosis and one septic shock. Hematological toxicity grade 4 was seen in 78% of the patients, infection grade 4 in 8%. Radiotherapy was given to 16% of the patients. Response: Response rates at end of therapy: CR/CRu: 69%, PR: 22%, SD: 1%, PD: 4.5%. Seventeen patients (7%) were not treated according to protocol, either due to lack of response (6 patients) or due to toxicity (eleven patients). The majority of the PR patients were considered to have residual masses and not viable tumour tissue. Survival: Three year overall survival was 80% (95% CI +/− 6.5%) and three year treatment failure free time 67% (95% CI +/−8.0%). CNS events: Seven patients had a CNS relapse, all but one were isolated (4 intracerebral, 3 meningeal). All CNS relapses occurred within 6 months after inclusion. Conclusions:The results are promising with a low three year treatment failure rate, a low toxic death rate and fewer CNS events than expected. The CNS events might be further reduced by earlier CNS prophylaxis.The study was supported by an unrestricted grant from Amgen Disclosures:Holte:Roche: Honoraria, Research Funding; Amgen: Honoraria, Research Funding. LeppÃ: Roche: Honoraria. Bjorkholm:Roche: Research Funding. Jyrkkiö:Roche: Honoraria. Kolstad:Roche: Honoraria; Amgen: Honoraria. Fosså:Roche: Honoraria. φstenstad:Roche: Honoraria; Amgen: Honoraria. Eriksson:Amgen: Research Funding.

Clinical study of transcatheter arterial chemoembolization plus radiofrequency ablation in hepatocellular carcinoma by magnetic resonance imaging and functional diffusion-weighted imaging

To evaluate the apparent diffusion coefficient (ADC) value features of the lesions after transcatheter arterial chemoembolization (TACE) plus radiofrequency ablation in hepatocellular carcinoma (HCC) with 3.0T magnetic resonance imaging (MRI) and diffusion-weight imaging (DWI) and analyze the value of 3.0T DWI in detecting the pathological lesion features of post-TACE plus radiofrequency ablation in HCC. Twenty-eight HCC patients were enrolled to receive TACE firstly. Then all viable tumors around the lesions underwent radiofrequency ablation. At 1-4 months after radiofrequency ablation, 3.0T MRI and DWI (b = 600 sec/mm(2)) were performed to measure the ADC values of different lesions of post-TACE plus radiofrequency ablation. The features of MRI and ADC values of different lesions, the difference of contrast enhancement sequence and DWI in evaluating the lesions of post-TACE plus radiofrequency ablation were analyzed. Viable tumors occurred in 14 of 28 HCC patients after TACE plus radiofrequency ablation. The ADC values of necrotic tissues with lipiodol, necrotic tissues without lipiodol, viable tumors and normal liver tissues were 1.905 ± 0.487, 0.726 ± 0.116, 1.449 ± 0.054 and 1.777 ± 0.094 (10(-3) mm(2)/sec) respectively. There was no significant difference of ADC values between necrotic tissues with lipiodol and normal tissues (P = 0.115). But there were significant differences of ADC values among necrotic tissues with lipiodol, necrotic tissues without lipiodol and viable tumors (P < 0.05). The viable tumor tissues after TACE plus radiofrequency ablation appeared as nodular lesions with slightly heightened signal intensities around the necrotic tissues, the lesions with heterogeneous enhancement during arterial phase, portal vein phase and parenchymal phase. Necrotic tissues without lipiodol occurred outside necrotic tissues without lipiodol, around normal liver tissues, with low signal intensities on T2WI, without enhancement during arterial phase, portal vein phase and parenchymal phase. There were no significant difference between contrast enhancement and DWI sequence in detecting viable tumors after TACE plus radiofrequency ablation (P > 0.05). The ADC values of 3.0T MR DWI may be used to distinguish the viable residue or recurrent tumor tissues, necrotic tissues in HCC after TACE plus radiofrequency ablation.

Clinical significance of serum cytokeratin 19 fragment in the prediction of chemotherapy efficacy and prognosis in patients with advanced non-small cell lung cancer

背景与目的由于RECIST（Response Evaluation Criteria in Solid Tumors, RECIST）标准不能对存活肿瘤组织进行检测，也不能对所有无法测量病灶的非小细胞肺癌（non-small cell lung cancer, NSCLC）患者的疗效进行准确评估，本研究通过检测进展期NSCLC患者化疗前后血清细胞角蛋白19片段（cytokeratin 19 fragment, CYFRA21-1）表达水平的变化以评价其在预测进展期NSCLC患者化疗疗效及预后中的临床价值。方法采用全自动生化分析仪电化学发光免疫法检测112例初治的NSCLC患者化疗前和化疗2周期后血清CYFRA21-1表达水平的变化，应用受试者特征工作曲线（receiver operating characteristics curve, ROC）评价血清CYFRA21-1反应在诊断影像学缓解（objective response, OR）中的效能及其与预后的相关性。结果经一线铂类为基础的两药联合方案化疗2周期后，血清CYFRA21-1水平较化疗前基线水平明显下降。80例可评价影像学和血清学疗效的患者中，26.3%（21/80）的患者达到影像学OR。化疗2周期后40.0%（32/80）的患者血清CYFRA21-1水平下降≥60%（血清CYFRA21-1反应）。血清CYFRA21-1反应与影像学OR之间有明显的统计学相关性（P < 0.001）。所有患者的中位生存期为9.9个月，血清CYFRA21-1水平下降≥60%患者的生存期明显长于CYFRA21-1水平下降 < 60%的患者（12.3个月vs 8.9个月，P < 0.001）。单因素分析结果显示，血清CYFRA21-1基线水平、CYFRA21-1反应、PS评分及影像学OR是影响生存期的重要预后因素。Cox多因素生存分析证实，仅血清CYFRA21-1基线水平、CYFRA21-1反应及PS评分是影响预后生存期的独立因素，而OR则与预后无关。结论血清CYFRA21-1水平可敏感地反映影像学肿瘤体积大小的变化，可能是评价进展期NSCLC患者化疗疗效的替代指标，同时也是预测预后生存期的可信指标。

Evaluation of angiogenesis of VX2 soft tissue tumor by arterial spin labeling perfusion imaging

Objective To evaluate the relationship between the blood flow values generated from MR arterial spin labeling (ASL) perfusion imaging and pathologic indicators of angiogenesis including microvascular density (MVD) counts and vascular endothelial growth factor (VEGF) expression levels of VX2 carcinoma in rabbit soft tissue. Methods VX2 tumor was inoculated in the muscular tissue of right posterior limbs of 18 healthy New Zealand white rabbits ,on which arterial spin labeling perfusion imaging was performed by using flow sensitive alternating inversion recovery pulse sequence 3 to 4 weeks later. Arterial spin labeling images were transferred to an independent computer for post-processing and blood flow (BF) maps were generated from them. BF values were measured in 2-4 regions of interest (ROIs) for each tumor. The rabbits were sacrificed after MR imaging. The gross specimens of tumors were obtained and tumor tissues were taken from the non-necrotic regions corresponding to ROIs on BF maps. Immunohistochemical staining of the specimens was performed by using CD31 monoclonal antibody to calculate MVD counts, using VEGF antibody to calculate VEGF expression levels. Correlation between BF values and MVD counts as well as between BF values and VEGF expression levels was evaluated using Spearman correlative analysis.Results On BF maps, viable tumor tissues showed high BF values compared with muscle, but there were areas without blood perfusion in some tumors. Under microscope, the microvessels positively stained by CD31 appeared as light brown areas, and the cells positively staied by VEGF showed reddish brown areas within their cytoplasm. Totally 39 pieces of VX2 tumor tissue were analyzeed There was a significant positive correlation between the BF values(M =6. 4 ml · 100 g-1 · min-1 ) and MVD counts(M =6. 8) (r = 0. 906,P ＜ 0. 01 ), and no significant correlation between BF values and VEGF expression levels ( M = 8％ ) ( r =0. 116, P=0.483). Conclusion BF value can be used in evaluating angiogenesis of soft tissue tumor through its reflection of MVD counts, and thus may be helpful in evaluating the prognosis of soft tissue tumor and making plan for their treatment. Key words: Magnetic resonance imaging; Perfusion; Arterial spin labeling; Soft tissue tumor; Angiogenesis

Accumulation of CD133-positive glioma cells after high-dose irradiation by Gamma Knife surgery plus external beam radiation

Recent evidence suggests that a glioma stem cell subpopulation might contribute to radioresistance in malignant gliomas. To investigate this hypothesis, the authors examined recurrent malignant gliomas for histopathological changes after high-dose irradiation with Gamma Knife surgery (GKS) and external beam radiation therapy (EBRT). Thirty-two patients with malignant gliomas (Grade 3 in 8 patients, Grade 4 in 24) underwent GKS in combination with EBRT. Serial MR and L-[methyl-(11)C] methionine PET images were employed to assess remnant or recurrent tumors after GKS. Twelve patients underwent surgical removal after GKS and EBRT. Histological sections were subjected to immunohistochemistry for MIB-1, factor VIII, and stem cell markers, nestin and CD133. The site of GKS treatment failure was local in 16 (76.2%) of 21 patients with glioblastomas showing progression; in 9 of these 16 patients, the recurrence clearly arose within the target lesion of GKS. Histopathological examination after GKS and EBRT showed variable mixtures of viable tumor tissues and necrosis. Viable tumor tissues exhibited high MIB-1 indices but reduced numbers of tumor blood vessels. There was marked accumulation of CD133-positive glioma cells, particularly in remnant tumors within the necrotic areas, in sections obtained after GKS plus EBRT, whereas CD133-positive cells appeared very infrequently in primary sections prior to adjuvant treatment. The results indicate that CD133-positive glioma stemlike cells can survive high-dose irradiation, leading to recurrence, despite prolonged damage to tumor blood vessels. This could be an essential factor limiting the effectiveness of GKS plus EBRT for malignant gliomas.