[A Case Report of Retroperitoneal Liposarcoma Resected Six Times for 16 Years].

We report of a long-surviving patient with retroperitoneal liposarcoma that required 6 surgeries in 16 years. A 62-year-old man was diagnosed with liposarcoma, which was first excised in 2001. Thereafter, we excised recurrences in the retroperitoneum with the left kidney in February 2004. We excised recurrences with the left half of the colon in November 2007 and February 2010 and recurrences with a part of the intestine in November 2014. This time, we excised recurrences under the right abdominal rectus muscle and near the left half of the colon. The pathological diagnosis was well-differentiated liposarcoma. There is currently no evidence of recurrence 16 years after the first recurrence excision. In this case, active excision of recurrences and identification of high-grade dedifferentiated-type liposarcomas were factors of long survival.