Anca L Grosu

Universitetet i Tromsø, Tromsø, Troms, Norway

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Publications (121)216.75 Total impact

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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: 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. · 1.36 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
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    ABSTRACT: High and continuously increasing research activity related to different aspects of pathogenesis, epidemiology, diagnosis and treatment of glioblastoma has been performed between 2006 and 2010. Different measures of impact, visibility and quality of published research are available, each with its own pros and cons. For this review, article citation rate was chosen. Articles were identified through systematic search of the abstract database PubMed followed by analyses of total number of citations and proportion of highly cited articles, arbitrarily defined as those with ≥100, 50-99, and 25-49 citations, respectively (citation database Scopus). Overall 5831 scientific articles on the subject were published during this time period. 1.5% of all articles accumulated at least 100 citations, 3.2% were cited between 50 and 99 times, and 7.5% were cited between 25 and 49 times. Among the 10 most cited articles, 7 reported on genomic analyses, molecular subclasses of glioblastoma and/or stem cells. Overall, 18 randomized clinical trials were published between 2006 and 2010, including those with phase II design. Thirty-nine percent of them accumulated at least 50 citations and 72% were cited at least 25 times. In general, annual citation rate appeared to gradually increase during the first 2-3 years after publication before reaching high levels. A large variety of preclinical and clinical topics achieved at least 25 citations. However, areas such as quality of life, side effects, and end-of-life care were underrepresented. Efforts to increase their visibility might be warranted.
    Clinical neurology and neurosurgery 04/2012; 114(9):1207-10. · 1.30 Impact Factor
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    ABSTRACT: In patients with brain metastases from non-small cell lung cancer, the prognostic impact of primary tumour histology, a feature with increasing implications for choice of systemic therapy, is not well defined. Therefore, a multi-institutional analysis was performed: retrospective uni- and multivariate analyses in 209 patients treated with different approaches including surgery and radiosurgery. While squamous cell and large cell carcinoma patients had comparable survival, those with adenocarcinoma survived significantly longer. In multivariate models, adenocarcinoma histology was confirmed as independent prognostic factor, which complements both recursive partitioning analysis (RPA) classes and diagnosis-specific graded prognostic assessment (GPA). When evaluated together with primary tumour control, extracranial metastases, number of brain metastases, age and performance status as individual covariates rather than RPA or GPA score, adenocarcinoma histology again emerged as significant prognostic factor. A significant but small survival advantage for patients with adenocarcinoma was evident already in the time period before drugs such as pemetrexed and epidermal growth factor receptor tyrosine kinase inhibitors were available. However, the gap has widened in recently treated patients. Comparable to patients without brain metastases, primary tumour histology should be taken into account when assessing patients' prognosis and recommending treatment strategy.
    Medical Oncology 04/2012; 29(4):2664-8. · 2.14 Impact Factor
  • L Götz, T S Spehl, W A Weber, A L Grosu
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    ABSTRACT: Positron emission tomography (PET) and single photon computed emission tomography (SPECT) have been evaluated in several studies for radiation treatment planning in patients with primary brain tumors. PET with the glucose analogue fluorodeoxyglucose has been found to be of limited use for radiation treatment planning because the high physiologic glucose use of normal gray matter makes delineation of tumors challenging. In contrast, there is considerable evidence that PET or SPECT with radiolabeled amino acid or amino acid analogues provides valuable information for the delineation of gliomas. Increased amino acid uptake has been found to be a more specific marker for viable tumor tissue than signal abnormalities on MRI. In addition, increased amino acid uptake is frequently observed in tumor areas that have not caused a disruption of the blood brain barrier. Therefore, PET and SPECT with radiolabeled amino acids provide a unique opportunity to visualize the infiltrative growth of gliomas and use this information for radiation treatment planning.
    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... 04/2012; 56(2):163-72. · 1.92 Impact Factor
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    ABSTRACT: Background. High and continuously increasing research activity related to different aspects of prevention, prediction, diagnosis and treatment of brain metastases has been performed between 1990 and 2010. One of the major databases contains 2695 scientific articles that were published during this time period. Different measures of impact, visibility, and quality of published research are available, each with its own pros and cons. For this overview, article citation rate was chosen. Results. Among the 10 most cited articles, 7 reported on randomized clinical trials. Nine covered surgical or radiosurgical approaches and the remaining one a widely adopted prognostic score. Overall, 30 randomized clinical trials were published between 1990 and 2010, including those with phase II design and excluding duplicate publications, for example, after longer followup or with focus on secondary endpoints. Twenty of these randomized clinical trials were published before 2008. Their median number of citations was 110, range 13-1013, compared to 5-6 citations for all types of publications. Annual citation rate appeared to gradually increase during the first 2-3 years after publication before reaching high levels. Conclusions. A large variety of preclinical and clinical topics achieved high numbers of citations. However, areas such as quality of life, side effects, and end-of-life care were underrepresented. Efforts to increase their visibility might be warranted.
    The Scientific World Journal 01/2012; 2012:721598. · 1.73 Impact Factor

Publication Stats

1k Citations
216.75 Total Impact Points

Institutions

  • 2011–2013
    • Universitetet i Tromsø
      • Faculty of Health Sciences
      Tromsø, Troms, Norway
  • 2010–2013
    • University of Freiburg
      Freiburg, Baden-Württemberg, Germany
  • 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