title: Liposarcoma simulating a Baker's cyst: a case study.
abstract: We present a case of liposarcoma in a 65-year-old man in whom the tumor first appeared as a soft, cystic mass at the medial margin of the left popliteal fossa. The mass simulated a Baker's cyst. The patient remained untreated for almost 7 months from the discovery of the mass. With worsening pressure symptoms, a biopsy was done that confirmed the clinical diagnosis of liposarcoma. The leg was amputated, but the patient died 2 years later with clinical evidence of pulmonary metastasis. By presenting this case report, we stress the importance of carefully investigating for malignancy all masses presenting as a Baker's cyst in persons past middle age.
mesh_terms: D000368:Aged; D003560:Cysts / Q000175:diagnosis*; D003951:Diagnostic Errors; D006801:Humans; D007717:Knee; D008080:Liposarcoma / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D012983:Soft Tissue Neoplasms / Q000175:diagnosis* / Q000473:pathology