Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    ISSN: 1432-2161
    Schlagwort(e): Bone tumour ; Bone neoplasm ; Ewing's sarcoma ; MR imaging ; Chemotherapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Magnetic resonance (MR) imaging was performed in 26 patients with Ewing's sarcoma of bone preceding and following neoadjuvant chemotherapy, to assess tumour response non-invasively prior to surgery. T1- and T2-weighted spin echo images were obtained. Changes including intra- and extramedullary signal intensities, tumour demarcation, tumour volume and the appearance of residual extramedullary tumour were compared with histopathology of the resected specimens. Reduction of tumour volume was significantly higher in good responders. Other single parameters did not correlate with histologic tumour response. However, when several MR parameters summarized in a classification system were combined, a positive correlation with histopathologic response was found. A limited decrease of tumour volume (〈25%) and/or residual soft tissue mass following chemotherapy correlated with a poor response. An inhomogeneous, well-defined cuff of abnormal tissue encircling the bone and/or radiological disappearance of the soft tissue tumour component following chemotherapy correlated with good response. Twenty-three out of 26 patients were correctly classified by MR as good or poor responders. Minimal residual disease (〈10% of the entire tumour volume), observed histologically, could not be identified with MR imaging. Tumour volume reduction and residual extramedullary tumour, rather than changes of signal intensity, are major features for evaluating the response to chemotherapy in Ewing's sarcoma.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    ISSN: 1432-2161
    Schlagwort(e): Key words Osteosarcoma ; Distal femur ; MR imaging ; Limb salvage surgery ; Surgical planning
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract  Objective. To analyse to what extent MR imaging based decisions were correct in determining the surgical procedure in patients with osteosarcoma of the distal femur. Design. We compared the findings on MR imaging that determined the surgical strategy with the actual surgical findings or histopathological specimen. We assessed to what extent MR images could be used to determine the surgical procedure in patients with osteosarcoma. Patients. Between 1985 and 1992, 34 patients with an osteosarcoma were treated. Two patients had a low-grade osteosarcoma. Thirty-two patients with a high-grade osteosarcoma of the distal femur (17 stage IIB, 15 stage III) were included in this study. Surgical options consisted of either limb salvage surgery or ablative surgery, which included the Van Nes-Borggreve rotationplasty. Limb salvage surgery consisted of extra-articular or transarticular resection, followed by reconstruction. Surgery was planned depending on the local extent of the tumour as depicted on the MR studies, coupled with data from the biopsy, age, patient compliance and histological grade. Follow-up was available in all patients. Nine of 17 patients graded as IIB were alive with an average follow-up of 68 months (range 46–109 months), of whom one has metastases. No local recurrence was encountered. Results. If no tumour involvement on MR imaging was found and this was used as a determining factor, this proved to be correct at subsequent analysis. We found that in eight of 11 cases, when MR images suggested a close relationship between tumour and nerve, an oncologically safe plane could be achieved during surgery. In three, a free plane could not be accomplished, as confirmed at histopathological examination. Hence, when nerve involvement was equivocal on MR imaging we found it valuable to reassess nerve involvement during surgery and reconsider limb salvage surgery. When the decisive factor was the vascular involvement and tumour extension was read as equivocal, it was possible to obtain a oncologically safe plane in six of 13 cases. When comprehensive tumour involvement of any structure was noted pre-operatively, it proved to be correct at histopathological examination, except for one case of assumed vascular involvement that proved to be free. Conclusions. If no tumour involvement of a structure was found on MR imaging and this was used as a determining factor, this proved to be correct. When nerve involvement was equivocal on MR imaging we found it valuable to reassess nerve involvement during surgery and reconsider limb salvage surgery. Extensive tumour involvement of any structure, as shown by MR imaging, could be used correctly as a decisive argument in planning a surgical procedure.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 1432-2161
    Schlagwort(e): Key words Clear cell sarcoma ; Malignant melanoma of soft parts ; MRI ; Magnetic resonance ; Neoplasm
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract  Objective. To evaluate MR imaging and pathology findings in order to define the characteristic features of clear cell sarcoma of the soft tissues (malignant melanoma of the soft parts). Design and patients. MR examinations of 21 patients with histologically proven clear cell sarcoma of the musculoskeletal system were retrospectively reviewed and assessed for shape, homogeneity, delineation, signal intensities on T1- and T2-weighted images, contrast enhancement, relationship with adjacent fascia or tendon, secondary bone involvement, and intratumoral necrosis. In 19 cases the pathology findings were available for review and for a comparative MR-pathology study. Results. On T1-weighted images, lesions were isointense (n=3), hypointense (n=7) or slightly hyperintense to muscle (n=11). Immunohistochemical examination was performed in 17 patients. All 17 specimens showed positivity for HMB-45 antibody. In nine of 11 lesions with slightly increased signal intensity on T1-weighted images, a correlative MR imaging-pathology study was possible. All nine were positive to HMB-45 antibody. Conclusions. Clear cell sarcoma of the musculoskeletal system often has a benign-looking appearance on MR images. In up to 52% of patients, this lesion with melanocytic differentiation has slightly increased signal intensity on T1-weighted images compared with muscle. As the presence of this relative higher signal intensity on T1-weighted images is rather specific for tumors displaying melanocytic differentiation, radiologists should familiarize themselves with this rare entity and include it in their differential diagnosis when confronted with a well-defined, homogeneous, strongly enhancing mass with slightly higher signal intensity compared with muscle on native T1-weighted images.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...