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  • 11
    ISSN: 1435-2451
    Keywords: Follicular thyroid carcinoma ; Morphology ; Prognosis ; DNA-cytophotometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In einer retrospektiven Studie an 95 folliculären Schilddrüsencarcinomen wurden verschiedene morphologische und klinisch-biologische Parameter auf ihre prognostische Bedeutung geprüft. Das klinische Verhalten der Tumoren wurde vorrangig durch Vorhandensein oder Fehlen einer Kapselbegrenzung bestimmt: Grob invasive Carcinome zeigten sechsfach häufiger einen letalen Verlauf als gekapselte Neoplasien. Ein ungünstigeres Verhalten ergab sich ferner bei Manifestation des Tumors im höheren Lebensalter (Schwellenalter: 52 Jahre) und bei Nachweis einer oxyphilen Differenzierung, weiterhin bei Vorliegen von Lymphknotenmetastasen, einer Halsweichteilinfiltration und - im Fall gekapselter Carcinome - von Fernmetastasen. Dagegen hatten die Faktoren Differenzierungsgrad und Geschlecht keinen signifikanten Einfluß auf die Prognose. Bei 22 Tumoren erfolgten cytophotometrische und flußcytometrische DNS-Bestimmungen. Der diagnostische Nutzen dieser Verfahren war dadurch limitiert, daß an Hand der DNSHistogramme in der Mehrzahl der Carcinome keine eindeutige Dignitätsbeurteilung getroffen werden konnte. Dagegen erwiesen sie sich als brauchbares Instrument für die Prognosebeurteilung individueller grob invasiver Tumoren. Die diagnostische, differentialtherapeutische und prognostische Bedeutung der Befunde sowie deren Relevanz für die Subklassifikation folliculärer Schilddrüsencarcinome wird diskutiert.
    Notes: Summary A retrospective study of 95 follicular thyroid carcinomas was conducted to evaluate the prognostic value of different morphological and clinical features. The biological behaviour of these tumours was primarily influenced by presence or absence of a capsule type of confinement: the frequency of lethal outcome among widely invasive carcinomas was six times higher than among encapsulated neoplasms. Furthermore, dismal prognosis could be demonstrated for tumours occurring in older patients (with a sharp break in the prognosis at the age of 52 years) and for those lesions which displayed oxyphilic metaplasia. The same effect was shown for presence of lymph node metastasis, tumour invasion of the cervical soft tissue and, for the case of encapsulated carcinomas, distant haematogenous spread. Conversely, the degree of differentiation and the patients' sex proved to have no significant influence on prognosis. In 22 carcinomas, cytophotometric and flow-cytometric determinations of DNA values were performed. These procedures revealed to have only limited diagnostic value, since for the majority of the tumours, benignancy or malignancy could not be judged from the DNA histograms. However, DNA measurements proved to contribute valuable information for the prognosis in individual cases of widely invasive follicular carcinomas. The discussion focuses on the diagnostic, therapeutic and prognostic relevance of these findings and on their impact on subclassification of follicular thyroid carcinomas.
    Type of Medium: Electronic Resource
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  • 12
    ISSN: 1619-7089
    Keywords: Key words: Single-photon emission tomography ; Glioma ; l-3-[123I]iodo-α-methyltyrosine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. Single-photon emission tomography (SPET) with the amino acid analogue l-3-[123I]iodo-α-methyl tyrosine (IMT) is helpful in the diagnosis and monitoring of cerebral gliomas. Radiolabelled amino acids seem to reflect tumour infiltration more specifically than conventional methods like magnetic resonance imaging and computed tomography. Automatic tumour delineation based on maximal tumour uptake may cause an overestimation of mean tumour uptake and an underestimation of tumour extension in tumours with circumscribed peaks. The aim of this study was to develop a program for tumour delineation and calculation of mean tumour uptake which takes into account the mean background activity and is thus optimised to the problem of tumour definition in IMT SPET. Using the frequency distribution of pixel intensities of the tomograms a program was developed which automatically detects a reference brain region and draws an isocontour region around the tumour taking into account mean brain radioactivity. Tumour area and tumour/brain ratios were calculated. A three-compartment phantom was simulated to test the program. The program was applied to IMT SPET studies of 20 patients with cerebral gliomas and was compared to the results of manual analysis by three different investigators. Activity ratios and chamber extension of the phantom were correctly calculated by the automatic analysis. A method based on image maxima alone failed to determine chamber extension correctly. Manual region of interest analysis in patient studies resulted in a mean inter-observer standard deviation of 8.7%±6.1% (range 2.7%–25.0%). The mean value of the results of the manual analysis showed a significant correlation to the results of the automatic analysis (r = 0.91, P〈0.0001 for the uptake ratio; r = 0.87, P〈0.0001 for the tumour area). We conclude that the algorithm proposed simplifies the calculation of uptake ratios and may be used for observer-independent evaluation of IMT SPET studies. Three-dimensional tumour recognition and transfer to co-registered morphological images based on this program may be useful for the planning of surgical and radiation treatment.
    Type of Medium: Electronic Resource
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