The application of multiple b value DWI in evaluating the short-term efficacy of cyberknife for locally advanced pancreatic cancer / 中华胰腺病杂志

ABSTRACT

Objective To explore the value of Multiple b value DWI ( MbDWI ) in the short-term efficacy evaluation of cyberknife radiotherapy for locally advanced pancreatic cancer ( LAPC ) .Methods A total of 36 patients underwent both conventional sequence and respiratory triggered MbDWI ( b=0, 25, 50, 75, 100, 150, 200, 400, 600, 800, 1 000 s/mm2 ) before cyberknife radiotherapy, 1month and 3 months after the radiotherapy, respectively.ADCtot, f, Dfast and Dslow were calculated using single and double exponential model and the changes before and after radiotherapy were observed.Results Before radiotherapy, 1 month and 3 months after radiotherapy, the ADCtot values of solid lesions were (1.56 ±0.29) ×10-3 mm2/s, (1.75 ±0.31) ×10 -3 mm2/s and (18.6 ± 0.46) ×10 -3 mm2/s;the values of Dslow were (1.10 ±0.73) × 10 -3 mm2/s, ( 1.19 ±0.97 ) ×10 -3 mm2/s and ( 1.49 ±04.6 ) ×10 -3 mm2 s/; the values of Dfast were (83 .33 ±62 .57) ×10 -3 mm2/s,(124.57 ±123.10) ×10 -3 mm2/s and (108.07 ±96 .67) ×10 -3 mm2 /s; f values were (26.81 ±23.74)%,(23.61 ±22.75)% and (21.34 ±15.36)%, respectively.ADCtot values 1 month and 3 months after treatment were significantly higher than those before treatment and Dslow 3 months post-treatment was higher than that before treatment, and the differences were statistically significant ( both P<0.05) and no other differences between two groups were significant.There were no statistical differences on Dfast and f before and after radiotherapy.Conc lusions ADCtot and Dslow both showed a significant growth trend after cyberknife radiotherapy.The advanced degree of parenchymal cystic in the targeted lesion could reflect the short-term efficacy of cyberknife treatment.