Liver Function Investigation With SPECT

Patients with cancers of the liver who are not suitable for surgery or chemo/radio embolisation are often treated with stereotactic ablative body radiotherapy (SABR). SABR results in high local control rates but, similar to other treatment modalities, carries risk of damage to healthy surrounding liver. This study aims to use a novel nuclear medicine imaging tracer, 99mTcMebrofenin, to evaluate liver function before and after radiotherapy. Patients will have a 99mTcMebrofenin scan performed \< 2 weeks before radiotherapy and 1 and 6 months after radiotherapy. At the same time points, indocyanine green (ICG) and liver elasticity tests will be performed. These are global measures of liver function, whereas 99mTcMebrofenin is both global and local. From the imaging data, the Investigators will be able to correlate change in local liver function in each sub volume of the liver with the radiotherapy dose it received. The Investigators will be able to thus measure the effect of radiotherapy on global and local liver function.