Intra‐abdominal desmoid‐type fibromatosis successfully resected using laparoscopic fluorescence imaging with indocyanine green after intersphincteric resection for rectal cancer

Successful resection of intra-abdominal tumors using indocyanine green (ICG) fluorescence imaging has not been reported. Here, we report a rare case of an intra-abdominal desmoid-type fibromatosis successfully resected using this technique after intersphincteric resection (ISR) for rectal cancer. One year after ISR for rectal cancer in a 47-year-old man, computed tomography showed a 50-mm intra-abdominal tumor near the left common iliac vein. Surgical resection was performed. The tumor was located in the mesentery of the remnant rectum after ISR. ICG fluorescence imaging confirmed the blood supply to the mesentery of the distal remnant rectum after tumor excision. The anal canal was successfully preserved without creating a permanent colostomy. The tumor was safely resected with resection margins, diagnosed as desmoid-type fibromatosis. No tumor recurrence was observed 6 months post-resection. This was the first case report to demonstrate the utility of this technique for an intra-abdominal tumor resection.