(a) CT image with a contrast medium before carbon ion radiotherapy. The tumor is located in the right tenth rib and he complained of back pain. (b) CT image with a contrast medium 8 years after carbon ion radiotherapy. The tumor shrank and partially calcified. He had no complain. (c) CT image with a contrast medium before C-ion RT. (d) Dose distribution for the patient: 70.4 GyE in 16 fractions over 4 weeks (Courtesy of Dr. Reiko Imai)