Fig. 1

Images of a representative patient who underwent expanded polytetrafluoroethylene (ePTFE) spacer placement surgery. a Recurrence of chondrosarcoma (white arrow) broadly abuts the small intestine, sigmoid colon, and rectum (arrowhead). b Operative findings show that the ePTFE spacer (arrowhead) was inserted and sutured to the surrounding tissue at the left side of the tumor. c Postoperative computed tomography reveals that sufficient space between the tumor and the gastrointestinal tract was maintained by the ePTFE spacer. d The treatment plan shows that the clinical target volume was totally irradiated at more than 90% of the prescribed dose, and gastrointestinal tract was barely irradiated