[CT findings and risk factor analysis of hepatic injury induced by three-dimensional conformal radiation therapy]

To investigate the CT findings and define the risk factors for early hepatic injury induced by three- dimensional conformal radiation therapy in patients with primary liver cancer.

This study recruited 52 patients with primary liver cancer undergoing photon beam radiation at a total dose of 35 to 65 Gy (49.88+/-7.23 Gy) completed within 18 to 31 d. CT examinations were performed within 1 to 3 months after the completion of the therapy, and logistic regression was used to analyze the CT features of early hepatic injury, in an attempt to define the correlation of the injury occurrence with such factors as the patients' age, gender, treatment portal numbers, liver cirrhosis, transcatheter arterial embolization (TACE), postoperative recurrence, total radiation dose, target volume and fractional dose.

Thirty-one (59.6%) patients showed CT features of hepatic injury, displayed as the area with hypodensity in consistency with the radiation coverage. The risk factors correlated to the injury occurrence included the total dose, target volume and fractional dose, but not the patients'age, gender, treatment portal number, liver cirrhosis, TACE, postoperative recurrence differences and radiation-induced hepatic injury.

Early radiation-induced hepatic injury is related to fractional dose, total dose and target volume adopted in radiation therapy. Higher fractional dose, total irradiated dose and larger target volume may result in increased risk of injury.