[A Case of Primary Liposarcoma of Pancreas Difficult to Diagnose Preoperatively].

The patient was a woman in her 80s. Operative treatment was performed for papillary thyroid cancer(pT3N0M0)13 years ago. A follow-up CT scan 1 year ago revealed a skin, lung, and lymph node metastasis. At the same time, a tumor with a size of 24 mm was initially observed in the tail of the pancreas, which was considered to be pancreatic metastasis of thyroid papillary cancer and was followed up. Only the pancreatic lesions tended to gradually increase, although other lesions did not increase. Therefore, the patient was referred to our department. It was difficult to diagnose preoperatively. Thus, diagnostic and therapeutic laparoscopic distal pancreatectomy with splenectomy was performed. The pathological diagnosis was dedifferentiated liposarcoma. Postoperatively, a Grade B pancreatic fistula was observed, but the patient recovered conservatively and was discharged on postoperative day 55. Primary liposarcoma of the pancreas is extremely rare, and few cases have been reported. Primary liposarcoma of the pancreas is very difficult to diagnose preoperatively by only diagnostic imaging.