Integration molekularer Bildinformationen in die Planung und Applikation moderner Strahlentherapietechniken

Zusammenfassung

Neben anderen bildgebenden Verfahren, die heutzutage verfügbar sind, zeichnet sich die Positronen-Emissions-Tomografie (PET) durch die Möglichkeit aus, Veränderungen auf molekularer Ebene zu visualisieren. Die molekulare Bildgebung, in der Literatur oft synonym als „funktionelle“ oder „biologische“ Bildgebung bezeichnet, hat durch die Darstellung von Stoffwechselvorgängen im Körper bzw. in Tumoren eine zusätzliche Dimension in der Krebsdiagnostik und Therapie gebracht. Ihre erste Anwendung fand die PET in der Diagnostik und im Staging von verschiedenen Tumoren mit hoher diagnostischer Präzision. Moderne Strahlentherapie stellt immer mehr die Frage nach individualisierten Behandlungsstrategien, bei denen die (molekulare) Bildgebung eine wesentliche Rolle spielt. Die technischen Entwicklungen der letzten Jahre, vor allem die Fusionsmöglichkeiten der diversen Datensätze in der strahlentherapeutischen Planungs- und Konturierungssoftware, haben den Einsatz der PET in der Strahlentherapie ermöglicht. Um das ganze kurative Potenzial der modernen Hochpräzisions-Strahlentherapie ausnutzen zu können, ist eine sehr genaue Bildgebung notwendig, nicht zuletzt um die Zielvolumina exakt zu identifizieren. Langfristig könnten sich Konzepte einer inhomogenen Dosisverschreibung auf der Basis biologischer Bildgebung in der klinischen Anwendung etablieren und zu einer individualisierten, biologisch-adaptiven Therapie führen.

Abstract

Among various imaging modalities currently available, positron emission tomography (PET) has the potential to visualize processes on a molecular level. Molecular imaging, often also referred to as functional or biological imaging, brought a new dimension to diagnostics and therapy of cancer by providing images of metabolism and other processes in the human body and in tumours. PET was first applied for diagnostics and staging of various tumours with high diagnostic precision. Modern radiotherapy asks increasingly for individualized treatment strategies, taking molecular imaging into account. Technical developments over the last years, in particular methods to register various imaging modalities within software packages for treatment planning and target delineation, facilitated the use of PET imaging in radiotherapy. In order to exploit the full potential of modern high-precision radiotherapy, exact imaging procedures are necessary, for example for precise target volume definition. In the long run, concepts employing an inhomogeneous dose prescription based on biological imaging may become routine in clinical applications, leading to individualized, biologically adaptive therapy.

Schlüsselwörter

molekulare Bildgebung - Positronen-Emissions-Tomografie - Strahlentherapie - Therapieplanung

Key words

molecular imaging - positron emission tomography - radiotherapy - treatment planning

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