[A CASE OF RENAL UNDIFFERENTIATED/UNCLASSIFIED SARCOMA WITH LONG-TERM SURVIVAL AFTER PRIMARY AND METASTATIC LESIONS].

(Case) A 56-year-old woman who complained of urinary frequency and macrohematuria. Abdominal US, enhanced CT and MRI revealed a left renal tumor. A left radical nephrectomy was performed in May 1997, and the pathological diagnosis was renal fibrosarcoma. Follow-up computed CT was performed routinely. A metastatic lesion in the right lung revealed 19 months after the nephrectomy.She underwent partial pneumonectomy in January 1999, and the pathological diagnosis was also fibrosarcoma. She was followed up until 2009 without recurrence.In 2015, she was admitted in the Department of Orthopedics due to femoral neck fracture in 2015, thus we could find out she was alive, tumor-free 18 years after the nephrectomy. We added the immunohistochemistical study to her specimen of kidney and lung, and the diagnosis was changed to undifferentiated/unclassified sarcoma. (Conclusion) Metastatic renal sarcoma has a poor prognosis in general. We experienced a long-term survival case of undifferentiated/unclassified renal sarcoma with lung metastasis, and report it with some literature review.