[Current diagnostics and therapy for carcinomas of the biliary tree and gallbladder]

An improved approach to external beam radiation therapy for intra-abdominal cavity lesions for rural cancer centers

Radiation therapy of abdominal lesions is problematic at best. The proximity of highly critical structures, tumor locations, and necessary margins combine to make prescription dose delivery with conventional 3-dimensional (3D) conformal techniques difficult. Others have tried to overcome these hurdles with newer modalities including intra-operative radiation therapy (IORT), intensity modulated radiation therapy (IMRT), and heavy particle irradiation. These techniques have had moderate success but are not readily available and are therefore limited in application. These factors have lead to the development of a modified, noncoplanar 4-field box technique that demonstrates significant improvement in critical structure sparing, i.e., kidney(s), bowel, and liver doses reduced while simultaneously improving isodose coverage to the target.

[Diagnostic imaging of liver tumours. Current status]

Nowadays, contrast enhanced ultrasound (CEUS) is an imaging technique equivalent to multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) for the detection and characterization of focal liver lesions. These methods have comparable sensitivity and specificity in differentiating a liver lesion as "benign" or "malignant". For benign lesions, CEUS is the recommended method of the choice. In unclear cases, or if CEUS is not available, MRI or CT are the methods of the second choice. If a benign tumor remains unclear, then a needle biopsy is recommended. In the case of a malignant tumor, it is necessary to use a second imaging technique besides CEUS. In addition to the detection and characterization of a liver tumor, CT and MRI provide information on the extrahepatic spread of a tumor, particularly into the lung or retroperitoneum. The rapid development of surgical and interventional approaches requires accurate information on the character and number of malignant liver lesions. Therefore, the combined use of CEUS and MDCT or MRI currently represents the most modern and optimal standard of imaging. The standardization of CT and MRI protocols has increased the general diagnostic level of these images. Adequate training and a certificate for the use of CEUS is recommended in order to maintain the high diagnostic level of this method (EFSUMB guide lines). An optimal interdisciplinary imaging strategy for focal liver lesions minimises unnecessary invasive or potentially harmful imaging and reduces health costs.