Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    German Medical Science; Düsseldorf, Köln
    In:  121. Kongress der Deutschen Gesellschaft für Chirurgie; 20040427-20040430; Berlin; DOC04dgch0723 /20041007/
    Publication Date: 2004-10-07
    Keywords: ddc: 610
    Language: German
    Type: conferenceObject
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Keywords: TUMORS ; ACID ; MALIGNANCIES ; BIODISTRIBUTION ; bombesin analog ; RADIATION-DOSIMETRY
    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 (6)(4)Cu-CB-TE2A-AR06 [((6)(4)Cu-4,11-bis(carboxymethyl)-1,4,8,11-tetraazabicyclo(6.6.2)hexadecane)-PEG (4)-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-LeuNH(2)] 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 (6)(4)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: (6)(4)Cu-CB-TE2A-AR06 shows very favorable characteristics for imaging prostate cancer. Future studies evaluating (6)(4)Cu-CB-TE2A-AR06 PET/CT for prostate cancer detection, staging, active surveillance, and radiation treatment planning are necessary.
    Type of Publication: Journal article published
    PubMed ID: 24578724
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    Abstract: In cancer, extracellular vesicles (EV) contribute to tumor progression by regulating local and systemic effects. Being released into body fluids, EV may be used in nanomedicine as a valuable source for diagnostic biomarkers. In this work, infrared and Raman spectroscopy were used for comprehensive comparative analysis of cancer versus non-cancer EV and patient screening. Two different EV fractions enriched in exosomes and microvesicles were isolated by differential centrifugation from serum and plasma of cancer and non-cancer patients and from serum and plasma of a healthy donor. The EV fractions were then subjected to drop-coating deposition and drying on calcium fluoride substrates. Reduction of alpha-helix-rich proteins and enhancement of beta-sheet-rich proteins as a cancer-specific blood EV signature was determined, and subsequently this feature was applied for a pilot study aiming to detect prostate cancer in a test cohort of patients with high-grade prostate carcinoma and benign hypoplasia.
    Type of Publication: Journal article published
    PubMed ID: 27965168
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    Abstract: Background: By targeting the prostate-specific membrane antigen (PSMA) on prostate cancer (PCa) cells PSMA-PET/CT shows great potential in locating the site of biochemical recurrence even at low PSA (Prostate-specific antigen)-levels. Accurate imaging of PCa recurrent lymph node metastases (LNM) is crucial for metastases directed therapies such as salvage-lymph node dissection (salvage-LND). Objective: To evaluate the diagnostic accuracy of PSMA-PET/CT for detection of affected lymph-node regions at salvage-LND for nodal recurrence of PCa. Design, setting and participants: 30 patients with the suspicion of exclusively nodal PCa-relapse after primary therapy underwent a template pelvic and/or retroperitoneal salvage-LND after whole body 68-Ga-PSMA-PET/CT. The diagnostic accuracy of PET/CT was evaluated in comparison to the histopathology of 965 resected lymph nodes (LN) dissected from 68 main regions (pelvic left/right, retroperitoneal) and 289 subregions (common iliac, external iliac, obturator, internal iliac, presacral, aortic-bifurcation, aortal, caval). LNM and tumor deposits in LNM were measured bidimensionally in the histopathology. PSMA-expression was analyzed by immunohistochemistry in LNM. Results: LNM were present in 11.4% of the resected LN (110/965) resulting in 45 positive main regions and 85 positive subregions. PET/CT was true positive in 41 main regions and 69 subregions. Three PET-negative main regions and 16 PET-negative subregions finally contained LNM, the majority of these false negative subregions (13/16) were in neighboring regions of true-positive subregions. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were: main region-based 93.2%, 100%, 100%, 88.9% and 95.6%, subregion-based 81.2%, 99.5%, 98.6%, 92.7 and 94.1%. Median short diameters of tumor deposits in LNM resected from false-negative subregions (1.3 mm) were significantly smaller than in LNM removed from true-positive subregions (5.5 mm, p〈0.0001). Based on anatomical subregions containing just one LNM, the necessary short diameter of tumor deposits in LNM required to reach a detection rate of 50% and 90% was estimated to be 〉/= 2.3 mm and 〉/= 4.5 mm, respectively. Conclusion: In men with biochemical PCa-relapse and positive PSMA-PET/CT, PET/CT detects metastatic affected anatomical regions with high accuracy at a main region and at a subregion-level. If the decision for salvage-LND is prompted by a positive PSMA-PET/CT, the size of metastases is crucial for accurate detection of affected regions. All LNM showed a clear PSMA-expression in the immunohistochemistry. Further studies need to investigate how to translate the high anatomical correlation observed between PET/CT and surgical findings into optimal approaches for target salvage-LND.
    Type of Publication: Journal article published
    PubMed ID: 28529650
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    Abstract: PURPOSE/BACKGROUND: [(18)F]fluoroethylcholine ((18)FECH) has been shown to be a valuable PET-tracer in recurrent prostate cancer (PCa), but still has limited accuracy. RM2 is a gastrin-releasing peptide receptor (GRPr) antagonist that binds to GRPr on PCa cells. Recent studies suggest that GRPr imaging with PET/CT is a promising technique for staging and restaging of PCa. We explore the value of GRPr-PET using the (68)Ga-labeled GRPr antagonist RM2 in a selected population of patients with biochemically recurrent PCa and a negative/inconclusive (18)FECH-PET/CT. MATERIAL AND METHODS: In this retrospective study 16 men with biochemical PCa relapse and negative (n = 14) or inconclusive (n = 2) (18)FECH-PET/CT underwent whole-body (68)Ga-RM2-PET/CT. Mean time from (18)FECH-PET/CT to (68)Ga-RM2-PET/CT was 6.1 +/- 6.8 months. Primary therapies in these patients were radical prostatectomy (n = 13; 81.3%) or radiotherapy (n = 3; 18.7%). 14/16 patients (87.5%) had already undergone salvage therapies because of biochemical relapse prior to (68)Ga-RM2-PET/CT imaging. Mean +/- SD PSA at (68)Ga-RM2-PET/CT was 19.4 +/- 53.5 ng/ml (range 1.06-226.4 ng/ml). RESULTS: (68)Ga-RM2-PET/CT showed at least one region with focal pathological uptake in 10/16 patients (62.5%), being suggestive of local relapse (n = 4), lymph node metastases (LNM; n = 4), bone metastases (n = 1) and lung metastasis with hilar LNM (n = 1). Seven of ten positive (68)Ga-RM2 scans were positively confirmed by surgical resection and histology of the lesions (n = 2), by response to site-directed therapies (n = 2) or by further imaging (n = 3). Patients with a positive (68)Ga-RM2-scan showed a significantly higher median PSA (6.8 ng/ml, IQR 10.2 ng/ml) value than those with a negative scan (1.5 ng/ml, IQR 3.1 ng/ml; p = 0.016). Gleason scores or concomitant antihormonal therapy had no apparent impact on the detection of recurrent disease. CONCLUSION: Even in this highly selected population of patients with known biochemical recurrence but negative or inconclusive (18)FECH-PET/CT, a (68)Ga-RM2-PET/CT was helpful to localize PCa recurrence in the majority of the cases. Thus, (68)Ga-RM2-PET/CT deserves further investigation as a promising imaging modality for imaging PCa recurrence.
    Type of Publication: Journal article published
    PubMed ID: 28417160
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Abstract: PURPOSE: The exact detection and delineation of the intraprostatic tumour burden is crucial for treatment planning in primary prostate cancer (PCa). We compared (68)Ga-HBED-CC-PSMA PET/CT with multiparametric MRI (mpMRI) for diagnosis and tumour delineation in patients with primary PCa based on slice by slice correlation with histopathological reference material. METHODOLOGY: Seven patients with histopathologically proven primary PCa underwent (68)Ga-HBED-CC-PSMA PET/CT and MRI followed by radical prostatectomy. Resected prostates were scanned by ex-vivo CT in a special localizer and prepared for histopathology. Invasive PCa was delineated on a HE stained histologic tissue slide and matched to ex-vivo CT to obtain gross tumor volume (GTV-)histo. Ex-vivo CT including GTV-histo and MRI data were matched to in-vivo CT(PET). Consensus contours based on MRI (GTV-MRI), PSMA PET (GTV-PET) or the combination of both (GTV-union/-intersection) were created. In each in-vivo CT slice the prostate was separated into 4 equal segments and sensitivity and specificity for PSMA PET and mpMRI were assessed by comparison with histological reference material. Furthermore, the spatial overlap between GTV-histo and GTV-PET/-MRI and the Sorensen-Dice coefficient (DSC) were calculated. In the case of multifocal PCa (4/7 patients), SUV values (PSMA PET) and ADC-values (diffusion weighted MRI) were obtained for each lesion. RESULTS: PSMA PET and mpMRI detected PCa in all patients. GTV-histo was detected in 225 of 340 segments (66.2%). Sensitivity and specificity for GTV-PET, GTV-MRI, GTV-union and GTV-intersection were 75% and 87%, 70% and 82%, 82% and 67%, 55% and 99%, respectively. GTV-histo had on average the highest overlap with GTV-union (57+/-22%), which was significantly higher than overlap with GTV-MRI (p=0.016) and GTV-PET (p=0.016), respectively. The mean DSC for GTV-union, GTV-PET and GTV-MRI was 0.51 (+/-0.18), 0.45 (+/-0.17) and 0.48 (+/-0.19), respectively. In every patient with multifocal PCa there was one lesion which had both the highest SUV and the lowest ADC-value (mean and max). CONCLUSION: In a slice by slice analysis with histopathology, (68)Ga-HBED-CC-PSMA PET/CT and mpMRI showed high sensitivity and specificity in detection of primary PCa. A combination of both methods performed even better in terms of sensitivity (GTV-union) and specificity (GTV-intersection). A moderate to good spatial overlap with GTV-histo was observed for PSMA PET/CT and mpMRI alone which was significantly improved by GTV-union. Further studies are warranted to analyse the impact of these preliminary findings for diagnostic (multimodal guided TRUS biopsy) and therapeutic (focal therapy) strategies in primary PCa.
    Type of Publication: Journal article published
    PubMed ID: 28042330
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2019-02-26
    Keywords: ddc: 610
    Language: German
    Type: conferenceObject
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1432-1041
    Keywords: Key words Bladder cancer ; Fluorescent photodetection ; Photodynamic diagnosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Abstract Objective: In an open study, the local and systemic side effects and pharmacokinetics of 5-aminolevulinic acid (5-ALA) and the fluorescent metabolite protoporphyrin IX (PPIX) were investigated after intravesical administration for the fluorescent photodetection of superficial bladder carcinoma. Patients and methods: In 20 patients with confirmed bladder carcinoma, 5-ALA was introduced into the bladder 2 h (15 patients) and 4 h (5 patients) before an elective endoscopic resection. The 5-ALA and PPIX levels in the plasma were determined before and up to 10 h after application, and in the urine 2 h or 4 h after application. Results: The plasma level of 5-ALA rose rapidly, the maximal concentration (340 ng/ml) being reached in 0.55 h (2 h) or 0.62 h (4 h). The elimination half-life of 5-ALA amounted to 0.74 h (2 h) or 0.79 h (4 h). In five of the patients, there was a measurable plasma concentration which ranged from the detection limit of 4.3 ng/ml to 14 ng/ml between 2 h and 5 h after application, and then fell below the detection limit after 9 h. Absorption of 5-ALA by the bladder was low, i.e. less than 1% of the total amount applied. During a period of observation of 96 h, no 5-ALA-specific side effects appeared. Conclusion: Because of the small quantity of 5-ALA resorbed following its intravesical administration, only minimal concentrations of PPIX that are responsible for producing side effects can be metabolised in the plasma. Therefore, no systemic side effects are to be expected after the intravesical administration of 5-ALA.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1432-0843
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We studied single doses of intravesical idarubicin (IDA) given as 1-h instillations to 33 patients with bladder tumors. The dose was escalated from 5 to 30 mg and the concentration, from 0.25 to 1.5 mg/ml for evaluation of the importance of both the total amount of drug and the drug concentration on the levels of IDA found in different tissues (tumor, mucosa and muscle). Additionally, plasma uptake over 24 h was studied. The results demonstrated that (1) the levels of IDA in extracts of bladder tumors were significantly higher than those in normal bladder tissue, (2) the incorporation of IDA into tumors depended on the total amount of drug instilled and on the concentration of drug in the instillation fluid, (3) cytotoxic concentrations of IDA were noted in all tumors when the total amount of drug instilled was 〉15 mg and the drug concentration in the instillation fluid was 〉0.33 mg/ml, and (4) plasma levels of IDA were negligible.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1434-0879
    Keywords: Idarubicin ; Intravesical chemotherapy ; Tissue concentration ; Plasma uptake ; Toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In the scope of a pharmacokinetic and dosefinding study 33 patients received instillations of idarubicin in 11 different doses 1 h before scheduled transurethral resection of bladder cancer. The dose was increased continuously from 5 to 30 mg and the concentration from 0.25–1.5 mg/ml. Idarubicin uptake into tissue was measured along with the serum level. The results showed a clear correlation of the tissue levels with dose and concentration. A significantly higher concentration of idarubicin was measured in the tumor in comparison with the mucosa. Absorption into the muscle was minimal and serum levels were low. Systemic toxicity was not observed, but there were signs of local toxicity in 50% of the subjects. Cytotoxic concentrations in the mucosa were reached at doses of over 15 mg and concentrations of over 0.5 mg/ml. A phase-II study is in preparation.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...