[A case of resection of a metastatic liver tumor that recurred after particle beam therapy].

Recently, the indications for particle beam therapy have been expanded to include metastatic liver tumors. However, its adverse effects on the treated liver are unclear, and the possibility of local recurrence after treatment should not be ignored. A 65-year-old man with advanced rectal carcinoma underwent low anterior resection. Resectable metastatic liver tumors were detected after adjuvant chemotherapy; however, he opted to undergo particle beam therapy. Nine months after treatment, a local recurrence was detected around the treated area, and central bisegmentectomy of the liver was performed as a salvage operation. The operation was technically complicated owing to severe adhesions and inflammatory changes in the liver parenchyma around the treated area. Pathological examination revealed advanced liver fibrosis at the treated area, in contrast with normal parenchyma in the untreated area. Although the procedure requires advanced surgical techniques, salvage surgery is a feasible option for recurrent liver tumors after particle beam therapy.