RADIATION TOLERANCE OF THE LIVER IN RELATION TO THE PRESERVED FUNCTIONAL-CAPACITY

The radiation tolerance of the liver was investigated in 12 patients, 11 of them with liver cirrhosis, treated for hepatocellular carcinoma by partial liver irradiation with doses between 50 and 77 Gy. The tole rance was assessed by the complication probability (Lyman's model), wh ich concerned the injured tissue itself, and by a prediction score use d for postsurgical liver failure, which concerned the preserved functi onal capacity, assuming that the greater than or equal to 30 Gy volume was equivalent to the resected volume. The prediction score correspon ded better with the observed risk of fatal liver failure than the comp lication probability. The liver volume after radiotherapy correlated l argely with the untreated volume and the low-dose volume. Thus the pre served functional capacity gives a better expression of the radiation tolerance than direct measures of the extent of injured tissue.