Anca L Grosu

University of Freiburg, Freiburg, Baden-Württemberg, Germany

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Publications (131)285.74 Total impact

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    ABSTRACT: (1) Evaluate the reproducibility of segmentation methods depending on the preselection region for tumour volume determination on 18F-fluoro-ethyl-tyrosine (FET) PET. (2) Evaluate the intra and inter-operator reproducibility of the manual delineation. (3) Compare this delineation with the segmentation methods.Materials and methodsEighteen FET PET of patients with glioblastoma were analysed. Preselection regions were determined prior to any segmentation. Two physicians delineated the tumour volume manually. The tumour volume was also delineated with a threshold method (40 and 70% of SUVmax), and a random walk based method. Pearson coefficient (r) (P < 0.05 for r > 0.468) and Jaccard indices (JI) were used to compare the volumes.ResultsManual delineation was reproducible with r = 0.97 and IJ = 0.65 for intra-operator, and r = 0.76 and IJ = 0.45 for inter-operator reproducibility. The preselection regions for a given lesion were different and the segmentation varied with the preselection region: r = 0.55 JI = 0.58; r = 0.85 JI = 0.83; r = 0.70 JI = 0.39 respectively for the threshold of 40%, 70% and the random walk. The segmentation differed form de manual delineation with r = 0.37 and JI = 0.16; r = 0.54 and JI = 0.42; r = 0.43 and JI = 0.37 respectively for the threshold of 40%, 70% and the random walk.Conclusion The reproducibility of the segmentation methods depends extensively on the preselection region. The intra-operator reproducibility of cerebral lesion delineation on FET PET is satisfactory. The inter-operator reproducibility could be improved.
    Médecine Nucléaire. 11/2014;
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    ABSTRACT: Radiation therapy is one of the cornerstones of modern multidisciplinary cancer treatment. Normal tissue tolerance is critical as radiation-induced side effects may compromise organ function and quality of life. The importance of normal tissue research is reflected by the large number of scientific articles, which have been published between 2006 and 2010. The present study identified important areas of research as well as seminal publications. The article citation rate is among the potential indicators of scientific impact. Highly cited articles, arbitrarily defined as those with ≥15 citations, were identified via a systematic search of the citation database, Scopus. Up to 608 articles per year were published between 2006 and 2010, however, <10% of publications in each year accumulated ≥15 citations. This figure is notably low, when compared with other oncology studies. A large variety of preclinical and clinical topics, including toxicity prediction, the dose-volume relationship and radioprotectors, accumulated ≥15 citations. However, clinical prevention or mitigation studies were underrepresented. The following conclusion may be drawn from the present study; despite the improved technology that has resulted in superior dose distribution, clinical prevention or mitigation studies are critical and must receive higher priority, funding and attention.
    Oncology letters 09/2014; 8(3):972-976. · 0.24 Impact Factor
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    ABSTRACT: The purpose of this work is to analyze patterns of care and outcome after stereotactic body radiotherapy (SBRT) for centrally located, early-stage, non-small cell lung cancer (NSCLC) and to address the question of potential risk for increased toxicity in this entity.
    Strahlentherapie und Onkologie 08/2014; · 4.16 Impact Factor
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    ABSTRACT: In many patients with brain metastases, the primary therapeutic aim is symptom palliation and maintenance of neurologic function, but in a subgroup, long-term survival is possible. Local control in the brain, and absent or controlled extracranial sites of disease are prerequisites for favorable survival. Stereotactic radiosurgery (SRS) is a focal, highly precise treatment option with a long track record. Its clinical development and implementation by several pioneering institutions eventually rendered possible cooperative group randomized trials. A systematic review of those studies and other landmark studies was undertaken. Most clinicians are aware of the potential benefits of SRS such as a short treatment time, a high probability of treated-lesion control and, when adhering to typical dose/volume recommendations, a low normal tissue complication probability. However, SRS as sole first-line treatment carries a risk of failure in non-treated brain regions, which has resulted in controversy around when to add whole-brain radiotherapy (WBRT). SRS might also be prescribed as salvage treatment in patients relapsing despite previous SRS and/or WBRT. An optimal balance between intracranial control and side effects requires continued research efforts.
    Radiation oncology (London, England). 07/2014; 9(1):155.
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    ABSTRACT: (18)F-Fluoroethylcholine ((18)F-FECh) is excreted via the urinary system with high activity accumulation in the urinary bladder. Furosemide and oral hydration can be administered concomitantly to reduce urinary activity to provide better detectability of retroperitoneal and pelvic lesions. Currently it is unknown if there is any effect of furosemide on (18)F-FECh uptake in organs, tissues and tumour lesions and the extent to which image quality along the urinary tract may be improved by furosemide.
    European journal of nuclear medicine and molecular imaging 06/2014; · 5.11 Impact Factor
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    ABSTRACT: Purpose. To develop a prognostic model for predicting survival after palliative reirradiation (PR). Methods and Materials. We analyzed all 87 PR courses administered at a dedicated palliative radiotherapy facility between 20.06.2007 (opening) and 31.12.2009. Uni- and multivariate survival analyses were performed, the previously published survival prediction score (SPS) was evaluated, and a PR-specific prognostic score was calculated. Results. In multivariate analysis, four parameters significantly influenced survival: performance status, use of steroids, presence of liver metastases, and pleural effusion. Based on these parameters, a 4-tiered score was developed. Median survival was 24.5 months for the favorable group, 9.7 and 2.8 months for the two intermediate groups, and 1.1 months for the unfavorable group (P = 0.019 for comparison between the two favorable groups and P ≤ 0.002 for all other pair-wise comparisons). All patients in the unfavorable group died within 2 months. Conclusion. The performance of PR-specific score was promising and might facilitate identification of patients who survive long enough to benefit from PR. It should be validated in independent patient groups, ideally from several institutions and countries.
    Journal of oncology. 01/2014; 2014:128240.
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    ABSTRACT: Ex vivo studies have shown that the gastrin releasing peptide receptor (GRPr) is overexpressed on almost all primary prostate cancers, making it a promising target for prostate cancer imaging and targeted radiotherapy. Methods: Biodistribution, dosimetry and tumor uptake of the GRPr antagonist (64)Cu-CB-TE2A-AR06 [((64)Cu-4,11-bis(carboxymethyl)-1,4,8,11-tetraazabicyclo(6.6.2)hexadecane)-PEG4-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-LeuNH2] were studied by PET/CT in four patients with newly diagnosed prostate cancer (T1c-T2b, Gleason 6-7). Results: No adverse events were observed after injection of (64)Cu-CB-TE2A-AR06. Three of four tumors were visualized with high contrast [tumor-to-prostate ratio > 4 at 4 hours (h) post injection (p.i.)], one small tumor (T1c, < 5% tumor on biopsy specimens) showed moderate contrast (tumor-to-prostate ratio at 4 h: 1.9). Radioactivity was cleared by the kidneys and only the pancreas demonstrated significant accumulation of radioactivity, which rapidly decreased over time. Conclusion: (64)Cu-CB-TE2A-AR06 shows very favorable characteristics for imaging prostate cancer. Future studies evaluating (64)Cu-CB-TE2A-AR06 PET/CT for prostate cancer detection, staging, active surveillance, and radiation treatment planning are necessary.
    Theranostics 01/2014; 4(4):412-9. · 7.81 Impact Factor
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    ABSTRACT: Purpose The purpose of this work was to evaluate tumor control and side effects associated with fractionated stereotactic radiotherapy (FSRT) in the management of residual or recurrent pituitary adenomas. Patients and methods We report on 37 consecutive patients with pituitary adenomas treated with FSRT at our department. All patients had previously undergone surgery. Twenty-nine patients had nonfunctioning, 8 had hormone-producing adenoma. The mean total dose delivered by a linear accelerator was 49.4 Gy (range 45–52.2 Gy), 5 × 1.8 Gy weekly. The mean PTV was 22.8 ccm (range 2.0–78.3 ccm). Evaluation included serial imaging tests, endocrinologic and ophthalmologic examination. Results Tumor control was 91.9 % for a median follow-up time of 57 months (range 2–111 months). Before FSRT partial hypopituitarism was present in 41 % of patients, while 35 % had anterior panhypopituitarism. After FSRT pituitary function remained normal in 22 %, 43 % had partial pituitary dysfunction, and 35 % had anterior panhypopituitarism. Visual acuity was stable in 76 % of patients, improved in 19 %, and deteriorated in 5 %. Visual fields remained stable in 35 patients (95 %), improved in one and worsened in 1 patient (2.7 %). Conclusion FSRT is an effective and safe treatment for recurrent or residual pituitary adenoma. Good local tumor control and preservation of adjacent structures can be reached, even for large tumors.
    Strahlentherapie und Onkologie 11/2013; 189(11). · 4.16 Impact Factor
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    ABSTRACT: Purpose: To evaluate the interobserver variability of gross tumor volume (GTV) - delineation of Dominant Intraprostatic Lesions (DIPL) in patients with prostate cancer using published MRI criteria for multiparametric MRI at 3 Tesla by 6 different observers. 90 GTV-datasets based on 15 multiparametric MRI sequences (T2w, diffusion weighted (DWI) and dynamic contrast enhanced (DCE)) of 5 patients with prostate cancer were generated for GTV-delineation of DIPL by 6 observers. The reference GTV-dataset was contoured by a radiologist with expertise in diagnostic imaging of prostate cancer using MRI. Subsequent GTV-delineation was performed by 5 radiation oncologists who received teaching of MRI-features of primary prostate cancer before starting contouring session. GTV-datasets were contoured using Oncentra Masterplan(R) and iplan(R) Net. For purposes of comparison GTV-datasets were imported to the Artiview(R) platform (Aquilab(R)), GTV-values and the similarity indices or Kappa indices (KI) were calculated with the postulation that a KI > 0.7 indicates excellent, a KI >0.6 to <0.7 substantial and KI >0.5 to <0.6 moderate agreement. Additionally all observers rated difficulties of contouring for each MRI-sequence using a 3 point rating scale (1 = easy to delineate, 2 = minor difficulties, 3 = major difficulties). GTV contouring using T2w (KI-T2w = 0.61) and DCE images (KI-DCE = 0.63) resulted in substantial agreement. GTV contouring using DWI images resulted in moderate agreement (KI-DWI = 0.51). KI-T2w and KI-DCE was significantly higher than KI-DWI (p = 0.01 and p = 0.003). Degree of difficulty in contouring GTV was significantly lower using T2w and DCE compared to DWI-sequences (both p < 0.0001). Analysis of delineation differences revealed inadequate comparison of functional (DWI, DCE) to anatomical sequences (T2w) and lack of awareness of non-specific imaging findings as a source of erroneous delineation. Using T2w and DCE sequences at 3 Tesla for GTV-definition of DIPL in prostate cancer patients by radiation oncologists with knowledge of MRI features results in substantial agreement compared to an experienced MRI-radiologist, but for radiotherapy purposes higher KI are desirable, strengthen the need for expert surveillance. DWI sequence for GTV delineation was considered as difficult in application.
    Radiation Oncology 07/2013; 8(1):183. · 2.11 Impact Factor
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    ABSTRACT: Background and purpose: Heat shock Protein 90 (Hsp90) is a molecular chaperone that folds, stabilizes, and functionally regulates many cellular proteins involved in oncogenic signaling and in the regulation of radiosensitivity. It is upregulated in response to stress such a heat. Hyperthermia is a potent radiosensitizer, but induction of Hsp90 may potentially limit its efficacy. Our aim was to investigate whether the new Hsp90 inhibitor NVP-HSP990 increases radiosensitivity, thermosensitivity and radiothermosensitivity of human tumor cell lines. MATERIAL AND METHODS: U251 glioblastoma and MIA PaCa-2 pancreatic carcinoma cells were used. To determine clonogenic survival, colony forming assays were performed. Cell viability and proliferation were assesed by Trypan blue staining. Cell cycle and apoptosis analyses were performed by flow cytometry. DAPI staining was used to detect mitotic catastrophe. RESULTS: NVP-HSP990 increased the thermosensitivity, radiosensitivity and radio-thermosensitivity of both cell lines in clonogenic assays. 72 hours after irradiation with 4 Gy, a significant reduction in cell number associated with considerable G2/M acumulation and mitotic catastrophe as well as cell death by apoptosis/necrosis was observed. CONCLUSIONS: Treatment with NVP-HSP990 strongly sensitized U251 and MIA PaCa-2 cells to hyperthermia and ionizing radiation or combination thereof through augmentation of G2/M arrest, mitotic catastrophe and associated apoptosis.
    Radiation Oncology 02/2013; 8(1):42. · 2.11 Impact Factor
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    ABSTRACT: PURPOSE: PET has been proven to be helpful in the delineation of gross tumour volume (GTV) for external radiation therapy in several tumour entities. The aim of this study was to determine if [(11)C]choline PET could be used to localize the carcinomatous tissue within the prostate in order to specifically target this area for example with high-precision radiation therapy. METHODS: Included in this prospective study were 20 patients with histological proven prostate carcinoma who underwent [(11)C]choline PET/CT before radical prostatectomy. After surgical resection, specimens were fixed and cut into 5-mm step sections. In each section the area of the carcinoma was delineated manually by an experienced pathologist and digitalized, and the histopathological tumour volume was calculated. Shrinkage due to resection and fixation was corrected using in-vivo and ex-vivo CT data of the prostate. Histopathological tumour location and size were compared with the choline PET data. Different segmentation algorithms were applied to the PET data to segment the intraprostatic lesion volume. RESULTS: A total of 28 carcinomatous lesions were identified on histopathology. Only 13 (46 %) of these lesions had corresponding focal choline uptake. In the remaining lesions, no PET uptake (2 lesions) or diffuse uptake not corresponding to the area of the carcinoma (13 lesions) was found. In the patients with corresponding PET lesions, no suitable SUV threshold (neither absolute nor relative) was found for GTV segmentation to fit the volume to the histological tumour volume. CONCLUSION: The choline uptake pattern corresponded to the histological localization of prostate cancer in fewer than 50 % of lesions. Even when corresponding visual choline uptake was found, this uptake was highly variable between patients. Therefore SUV thresholding with standard algorithms did not lead to satisfying results with respect to defining tumour tissue in the prostate.
    European Journal of Nuclear Medicine 02/2013; · 4.53 Impact Factor
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    ABSTRACT: OBJECTIVES: Identification of the most influential scientific publications and directions of mainstream reirradiation research. METHODS: A systematic search of the database Scopus (Elsevier B.V., www.scopus.com) was performed, which focused on the time period 1998-2010. Patterns of citation were analysed (total number of citations accumulated independently of their origin and proportion of highly cited articles, arbitrarily defined as those with ≥50 citations). RESULTS: Up to 64 articles were published each year. Numbers increased over time, especially after the year 2007. Among all 76 articles with at least 50 citations, 28 (37%) focused on head and neck cancer, 27 (36%) on brain tumours including metastases, and 5 (7%) on bone metastases. Most articles evaluated external beam approaches while 10 (13%) focused on brachytherapy. Many of the often quoted publications reported on stereotactic and/or intensity-modulated radiotherapy. Two (3%) reported on randomised clinical studies and 10 (13%) on non-randomised prospective clinical studies (single institution or cooperative group). Only two articles (3%) reported on experimental animal studies. CONCLUSIONS: The number of published reirradiation studies has increased in recent years. Many studies examined highly conformal and precise radiotherapy, in particular of brain and head and neck tumours. Given that few randomised clinical trials were published, efforts to increase this type of research activity are warranted.
    American Journal of Cancer Research 01/2013; 3(2):152-158. · 2.65 Impact Factor
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    I Götz, A L Grosu
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    ABSTRACT: In the treatment of patients suffering from malignant glioma, it is a paramount importance to deliver a high radiation dose to the tumor on the one hand and to spare organs at risk at one the other in order to achieve a sufficient tumor control and to avoid severe side effects. New radiation therapy techniques have emerged like intensity modulated radiotherapy and image guided radiotherapy that help facilitate this aim. In addition, there are advanced imaging techniques like Positron emission tomography (PET) and PET/CT which can help localize the tumor with higher sensitivity, and thus contribute to therapy planning, tumor control, and follow-up. During follow-up care, it is crucial to differentiate between recurrence and treatment-associated, unspecific lesions, like radiation necrosis. Here, too, PET/CT can facilitate in differentiating tumor relapse from unspecific changes. This review article will discuss therapy response criteria according to the current imaging methods like Magnet resonance imaging, CT, and PET/CT. It will focus on the significance of PET in the clinical management for treatment and follow-up.
    Frontiers in Oncology 01/2013; 3:104.
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    ABSTRACT: For some patients with recurrent, unresectable, and previously irradiated head and neck squamous cell carcinoma (HNSCC), reirradiation (re-RT) may be a curative option. Chemotherapy with epidermal growth factor receptor (EGFR) inhibition is established as palliative management. This retrospective single-institutional study investigates feasibility, toxicity, and outcome of reirradiation (re-RT) combined with EGFR blockade for these patients.Between June 2008 and June 2012, 23 patients with inoperable and previously irradiated HNSCC were reirradiated. Concomitant EGFR blockade (cetuximab) was given initially at 400 mg/m2 two days prior to re-RT and weekly (250 mg/m2) thereafter. PET/CT imaging was fused with planning CT in 8 patients.One patient died of anaphylactic shock during the first cetuximab administration; two discontinued treatment on their own request. In all, 20 patients completed re-RT (50.4–66.6 Gy) and received cetuximab as prescribed. Grade 3 acute side effects were documented for dermatitis (35 %), dysphagia (30 %), acneiform rash (30 %), and mucositis (15 %). The 1-year overall survival rate was 34.8 %. Median overall and progression-free survival times were 9 and 4.3 months, respectively. A multivariable analysis using the Cox regression model showed significant positive impact of acneiform rash (hazard ratio [HR] 0.1531, 95 % confidence interval [CI] 0.0383–0.6111), while a period from first radiation to re-RT longer than 120 months negatively (HR 0.1633, 95 % CI 0.0305–0.8734) influenced patient survival.re-RT with concurrent cetuximab was feasible. Compared to platinum-based chemotherapy with fluorouracil and cetuximab, this therapeutic approach did not demonstrate survival benefit. Prolonged intervals from first treatment to re-RT seem to be unfavorable.
    Strahlentherapie und Onkologie 01/2013; 189(10). · 4.16 Impact Factor
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    ABSTRACT: PurposeTo evaluate the value of dynamic contrast enhanced Magnetic Resonance Imaging (DCE-MRI) without endorectal coil (EC) in the detection of local recurrent prostate cancer (PC) after radical prostatectomy (RP). MATERIAL AND METHODS: Thirty-three patients with recurrent PC underwent DCE-MRI without EC before salvage radiotherapy (RT). At median 15 (mean 16+/-4.9, range 12--27) months after completion of RT all patients showed complete biochemical response. Additional follow up post RT DCE-MRI scans were available. Prostate specific antigen (PSA) levels at the time of imaging were correlated to the imaging findings. RESULTS: In 22/33 patients (67%) early contrast enhancing nodules were detected in the post-prostatectomy fossa on pre-RT DCE-MRI images. The average pre-RT PSA level of the 22 patients with positive pre-RT DCE-MRI findings was significantly higher (mean, 0.74+/-0.64 ng/mL) compared to the pre-RT PSA level of the 11 patients with negative pre-RT DCE-MRI (mean, 0.24+/-0.13 ng/mL) (p<0.001). All post-RT DCE-MRI images showed complete resolution of initial suspicious lesions. A pre-RT PSA cut-off value of >=0.54 ng/ml readily predicted a positive DCE-MRI finding. CONCLUSIONS: This is the first study that shows that DCE-MRI without EC can detect local recurrent PC with an estimated accuracy of 83% at low PSA levels. All false negative DCE-MRI scans were detected using a PSA cut-off of >=0.54 ng/mL.
    Radiation Oncology 10/2012; 7(1):185. · 2.11 Impact Factor
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    ABSTRACT: Recurrence of prostate cancer after radical prostatectomy is a common event. Salvage radiation therapy (RT) is the mainstay of treatment in cases with recurrence defined as PSA failure, offering the chance of cure. Multiple studies showed that the lower the PSA level at the beginning of salvage RT, the better the treatment outcome. There is evidence that higher radiation doses are associated with improved PSA relapse free rates. Four different recurrence patterns exist: 1) local recurrence in the prostatectomy bed only; 2) loco-regional metastases in the pelvic lymph nodes; 3) distant metastases (most commonly nodal or osseous); 4) a combination of local and distant recurrence. Modern functional imaging modalities like magnetic resonance imaging (MRI) and choline-PET/CT offer additional information to clinical and therapeutic variables and provide high accuracy depending on the level of PSA recurrence and PSA kinetics. These image modalities are valuable tools that can be used for gross tumor volume (GTV) definition in the RT-planning process in the salvage RT setting and guide interdisciplinary salvage therapy strategies in case of locoregional relapse. We discuss the impact of MRI and choline-PET/CT in the salvage setting from the radiation-oncologist point of view.
    The quarterly journal of nuclear medicine and molecular imaging: official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of... 10/2012; 56(5):409-20. · 1.92 Impact Factor
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    ABSTRACT: Assessment of cancer- and host-related prognostic factors has a long tradition in patients with brain metastases. In continuation of large-scale studies performed by the Radiation Therapy Oncology Group (RTOG) in the United States, the 4-tiered diagnosis-specific graded prognostic assessment (DS-GPA) score has been developed. It stratifies patients with common primary tumours metastasizing to the brain (malignant melanoma, lung, breast, kidney and gastrointestinal cancers) into subgroups with different prognoses. However, many patients in the DS-GPA study were treated with surgical resection or radiosurgery (SRS). The present multi-institutional analysis examined for the first time whether DS-GPA is a valid score in European patients managed in routine clinical practice. This was a retrospective analysis of 412 patients with primary malignant melanoma, lung, breast, kidney or gastrointestinal cancers. Survival was evaluated in uni- and multivariate tests. DS-GPA significantly predicted survival and outperformed initial GPA, a score that is not diagnosis-specific. Median survival by DS-GPA strata (all 412 patients) was 2.7, 3.6, 7.0 and 11.3 months in the 4 groups with 0-1, 1.5-2, 2.5-3 and 3.5-4 points, respectively. The previously published survival data (median 7.2 months for all patients) could not be replicated in this cohort (median 3.6 months). DS-GPA is a valid prognostic score that might improve shared decision making as well as patient stratification in prospective clinical trials.
    Medical science monitor: international medical journal of experimental and clinical research 06/2012; 18(7):CR450-5. · 1.22 Impact Factor
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    ABSTRACT: One of the most important biological characteristics of Glioblastoma multiforme (GBM) is high vascular density. Vadimezan (ASA404, DMXAA) belongs to the class of small molecule vascular disrupting agents (VDA) that cause disruption of established tumor vessels and subsequent tumor hemorrhagic necrosis. Its selective antivascular effect is mediated by intratumoral induction of several cytokines including tumor necrosis factor-α (TNF-α), granulocyte-colony-stimulating factor (G-CSF), interleukin 6 (IL-6) and macrophage inflammatory protein 1α (MIP-1α). Preclinical studies have demonstrated that ASA404 acts synergistically with taxanes. In this study, we investigated if treatment of mice bearing U251 human glioblastoma xenografts with ASA404 and taxol may be synergistic. Therapy response was evaluated by measuring changes in tumor size and metabolic activity using 18F-FDG PET (Fluorodeoxyglucose - positron emision tomography) imaging. U251 cells were inoculated s.c. in the right hind limb of NMRI-Foxn1nu athymic female nude mice. Animals were randomly assigned into 4 groups (7-9 animals/group) for treatment: control, taxol, ASA404, and ASA404 plus taxol. The animals received either a single dose of taxol (10 mg/kg), ASA404 (27.5 mg/kg), or taxol (10 mg/kg) plus ASA404 (27.5 mg/kg) administered i.p.; ASA404 was administred 24 h after the treatment with taxol. 4 and 24 h after treatment with ASA404 (28 and 48 h hours after treatment with taxol) 18 F-FDG PET scans were performed. The treatment with taxol did not affect the tumor growth in comparison to untreated controls. The treatment of animals with single dose ASA404 alone or in combination with taxol caused a significant delay in tumor growth. The combined treatment did not decrease the growth of the xenografts significantly more than ASA404 alone, but early changes in tumor 18 F-FDG uptake preceded subsequent growth inhibition. The tumor weights, which were determined at the end of treatment, were lower in case of combined treatment. The treatment with ASA404 alone or in combination with taxol showed antitumoral effects in our glioblastoma model probably through destruction of blood vessels. The implications for the anticancer effect of this compound warrant further preclinical studies. 18F-FDG PET appears to be a promising tool to monitor treatment with ASA404 early in the course of therapy.
    BMC Cancer 06/2012; 12:242. · 3.33 Impact Factor
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    ABSTRACT: Several previous publications suggested that younger patients with brain metastases have longer survival than older patients. However, detailed studies of younger patient groups are scarce. Therefore, a multi-institutional analysis of younger patients with brain metastases was performed (defined as adults with age <50 years). Prognostic factors for survival were examined by uni- and multivariate analyses and compared to those obtained in patients with age ≥50 years. Multivariate analysis of 106 patients (median age 44 years, range 23-49 years) revealed three independent prognostic factors for survival: performance status, extracranial metastases and primary tumor control. Survival was significantly better in patients treated after the year 2000 (median 9.4 months) as compared to those treated before the year 2000 (median 5.1 months, p = 0.04). This improvement appeared to be related to an increased use of surgery or radiosurgery (SRS) and decreasing numbers of patients with uncontrolled primary tumor. Irrespective of management approach, survival beyond 5 years was uncommon (actuarial rate 6 %; 17 % in patients treated with upfront surgery or SRS). In conclusion, more intense multidisciplinary approaches aiming at control both in the brain, extracranial metastatic sites, and primary tumor site might have contributed to gradual survival improvements in recent years. Nevertheless, further efforts are necessary to improve long-term survival.
    Clinical and Experimental Metastasis 05/2012; · 3.46 Impact Factor
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    ABSTRACT: Assessment of prognostic factors might influence treatment decisions in patients with brain metastases. Based on large studies, the diagnosis-specific graded prognostic assessment (GPA) score is a useful tool. However, patients with unknown or rare primary tumours are not represented in this model. A pragmatic approach might be use of the first GPA version which is not limited to specific primary tumours. This retrospective analysis examines for the first time whether the GPA is a valid score in patients not eligible for the diagnosis-specific GPA. It includes 71 patients with unknown primary tumour, bladder cancer, ovarian cancer, thyroid cancer or other uncommon primaries. Survival was evaluated in uni- and multivariate tests. The GPA significantly predicted survival. Moreover, improved survival was seen in patients treated with surgical resection or radiosurgery (SRS) for brain metastases. The older recursive partitioning analysis (RPA) score was significant in univariate analysis. However, the multivariate model with RPA, GPA and surgery or SRS versus none showed that only GPA and type of treatment were independent predictors of survival. Ideally, cooperative research efforts would lead to development of diagnosis-specific scores also for patients with rare or unknown primary tumours. In the meantime, a pragmatic approach of using the general GPA score appears reasonable.
    Strahlentherapie und Onkologie 04/2012; 188(8):692-5. · 4.16 Impact Factor

Publication Stats

1k Citations
285.74 Total Impact Points

Institutions

  • 2010–2014
    • University of Freiburg
      Freiburg, Baden-Württemberg, Germany
  • 2011–2013
    • Universitetet i Tromsø
      • Faculty of Health Sciences
      Tromsø, Troms, Norway
  • 2011–2012
    • Nordlandssykehuset Bodoe
      Bodø, Nordland, Norway
    • Universitätsklinikum Freiburg
      Freiburg an der Elbe, Lower Saxony, Germany
  • 2007–2008
    • Nordlandssykehuset HF
      Bodø, Nordland, Norway
  • 1999–2008
    • University of Technology Munich
      • Klinik und Poliklinik für Strahlentherapie und Radiologische Onkologie
      München, Bavaria, Germany
    • University Hospital München
      München, Bavaria, Germany
  • 1998–2007
    • Deutsches Herzzentrum München
      München, Bavaria, Germany