Imaging of tumor specific antigens and microenvironment

The events that drive tumor progression and metastatization initiate within the cancer cell itself, that accumulates mutations and de-differentiate until reaching a very unstable stage. But these events alone are not sufficient to maintain sustained metastasis development and growth. Support from the host is required in order to promote angiogenesis and inhibit immune response that would kill cancer cells. The sum of these events is the result of the interaction between the tumor and cellular or non-cellular components that surround the cancer cells. This concept gained more and more importance during the recent years due to the possibility to develop a wide range of therapeutic strategies to target those components and pathways involved in the establishment of tumor microenvironment. However, it has been reported that cancer lesions, even within the same patient, may express different markers, thus, needing two different therapeutic approaches. Therefore, there is the need of a non-invasive tool to characterize each lesion before planning the most appropriate therapy. This will allow to save money, time and reduce the side-effects as much as possible. In this scenario, nuclear medicine offers a wide set of potential radiopharmaceuticals to image markers expressed by both cancer cells and microenvironment allowing to plan the most appropriate therapy in each patient. In this thesis we present four different strategies to image tumor specific antigens and microenvironment focusing on cancer, immune system and angiogenesis.