[A case of retroperitoneal liposarcoma with inflammatory pseudotumor].

[well-differentiated liposarcoma]

A 54 -year -old man presented with pollakiuria and dysuria . Ultrasonography , computed tomography (CT ), and magnetic resonance imaging (MRI ) showed a retroperitoneal tumor 10 cm in diameter . Pathological examination of a transrectal biopsy specimen obtained from the patient revealed the presence of an inflammatory myofibroblastic tumor (IMT ). The patient underwent surgical resection of the tumor . Histopathologically , the tumor was composed of 3 parts : the largest part was compatible with an inflammatory pseudotumor : the second part , well-differentiated liposarcoma : and the third part , a myxoid liposarcoma . He has been followed up for 14 months ; but there was no evidence of local recurrence of the tumor . We believe that the inflammatory pseudotumor complicated in repairing the inflammation arising from the liposarcoma .