Liang PC et al. (2007) Dynamic MRI signals in the second week of radiotherapy relate to treatment outcomes of hepatocellular carcinoma: a preliminary result. Liver Int 27: 516–528

Radiation therapy (RT) has been shown to achieve reasonable local control of hepatocellular carcinoma (HCC). Liang and colleagues investigated whether dynamic contrast-enhanced MRI (DCEMRI) data obtained in the second week of an RT regimen could predict treatment outcomes in 19 patients with HCC.

The patients included in this study (mean age 64 years, 84.2% men) had not responded to local therapy, and had not received any treatment for ≥1 month before beginning RT. The tumor-targeted RT regime involved a total of 50 Gy administered in one 2 Gy daily fraction, 5 days per week, for 5 weeks. Patients underwent DCEMRI for the evaluation of change in signal intensity before RT, after 2 weeks' (20 Gy) RT, and 1 month after the end of the RT course (i.e. 9 weeks after commencement). The response of liver tumors was evaluated by conventional MRI.

DCEMRI initial enhancement slope (the steepest slope of the first rise on the time–intensity curve) and peak enhancement ratio ([maximum signal intensity – base signal intensity] ÷ base signal intensity) measurements of the tumor at week 2 were significantly higher in patients who had good local control of HCC than in those who had poor control (P = 0.005 and P = 0.017, respectively). The same DCEMRI measurements of hepatic parenchyma were significantly higher at week 2 in patients who developed recurrence or metastasis than in those who did not (slope P = 0.017, peak P = 0.033).

The authors conclude that DCEMRI performed after 2 weeks' RT might help predict local responses to RT in patients with HCC.