Molecular imaging and photodynamic therapy in hepatoblastoma.

Molecular imaging is a novel field in cancer research combining various in vivo imaging modalities with molecular biology. Different techniques such as magnetic resonance tomography (MRI), positron emission tomography (PET), optical imaging methods (bioluminescence, fluorescence), or combination of these are used in basic research as well as in patients in different tumor entities. In hepatoblastoma (HB), there are only few reports on molecular imaging methods in a preclinical (optical imaging) and clinical setting (PET, PET-CT). Unimprovable treatment outcomes of patients in advanced tumor stages require novel treatment approaches. Photodynamic diagnosis (PDD) and photodynamic therapy (PDT) are novel diagnostic and therapeutic tools. Photodynamic diagnosis allows in vitro and in vivo detection of tumor cells using their fluorescending behaviour. PDT is a novel anticancer treatment approach leading to tumor cell destruction via apoptosis. In hepatoblastoma, there are only few reports on in vitro and in vivo studies using this treatment modality. First results seem to be promising and further studies will be required to further evaluate these techniques and to transfer them into clinical settings. This paper reviews different modalities of molecular imaging, photodynamic diagnosis and photodynamic therapy in childhood hepatoblastoma.