Two Cases of Retroperitoneal Liposarcoma of which the Peroperative Aspiration Cytology was Useful for Diagnosis

We have experienced two cases of the retroperitoneal liposarcoma, which are relatively rare and scarcely experienced at daily clinical practice. At its diagnosis, though a qualitative diagnosis was impossible preoperatively, the peroperative aspiration cytology was very useful. Histologically, one was predominantly pleomorphic (poorly differentiated) type and the other was pledominantly myxoid (well differentiated) type (by WHO classification). This paper emphasized that the peroperative aspiration cytology was a very useful procedure for diagnoses of tumorous lesions of which especially preoperative diagnoses were uncertain.