Incorporating GSA-SPECT into CT-based dose-volume histograms for advanced hepatocellular carcinoma radiotherapy

Figure 1 A 58-year-old man with hepatocellular carcinoma with a maximum diameter of 18. 0 cm. A: Contrast-enhanced computed tomography; B: Single photon emission computed tomography with Tc-99m-galactosyl human serum albumin before radiotherapy; C: The merged image of A and B. The regions (1) without GSA accumulation in B correspond to main tumor located in the left lobe. The regions (2) of high accumulation in B correspond to functional liver. These regions were identified using the merged image (C); D: Dose distribution based on the CT simulation; E: GSA-SPECT image obtained 2 mo after RT shows regions without GSA accumulation (1) along the two high-dose beams, with preservation of functional liver (2); F: The extent of radiation-induced dysfunctional liver is shown as the gray area with a black border and was determined by comparing B and E. GSA: Galactosyl human serum albumin; SPECT: Single photon emission computed tomography; CT: Computed tomography; RT: Radiotherapy.