Nuclear physician Klaus Tatsch looks at a radiation liquid during an operation on a cancer patient by the new radiation treatment for liver tumours called Selective Internal Radiation Therapy (SIRT) in Munich's university hospital, October 17, 2006. SIRT targets a very high radiation dose to tumours within the liver, regardless of their cell of origin, number, size or location. The spheres are implanted using a catheter placed in the artery feeding the liver and travel via the blood stream, where the spheres are targeted to the tumours within the liver. REUTERS/Alexandra Beier (GERMANY)