History of retroperitoneal liposarcoma. Evaluate for response to treatment. PELVIS:UTERUS, ADNEXA: The uterus is displaced towards the left by the large right hemipelvis mass. Otherwise it is unremarkable. The adnexa are not clearly identified.BLADDER: The bladder is mostly collapsed and displaced by the large right hemipelvis mass.LYMPH NODES: No significant abnormality noted.BOWEL, MESENTERY: No significant abnormality noted.BONES, SOFT TISSUES: Demonstrated again is the heterogeneously enhancing mass in the right hemipelvis measuring 11.8 x 8.1 cm in maximal cross section (series 13/16), compared to 11.5 x 7.8 cm previously. In the craniocaudal dimension the lesion measures 12.9 cm (series 12/18). It contains heterogeneously intrinsic signal, including that of fat intensity compatible with states history of liposarcoma.The mass displaces the bladder, uterus and mesorectal fascia towards the left.The fat planes between the mass, the right piriformis muscle, uterus and bladder are indistinct, appearing similar to the prior study.The mass partially encases the right common and external iliac artery and vein, similar to the prior study. The lesion encases the right internal iliac artery and vein and their branches which are generally opacified, unchanged.The component of the lesion extending through the sacrosciatic notch to the level of the ischial tuberosity is not significantly changed in size. It encases the sciatic nerve as well as the more proximal sacral nerve roots. The tumor tracks along the sacral plexus to level of the right L5 and S1 neural foramen. The lesion abuts the right sacral ala and medial right iliac bone without definite osseous invasion, similar to prior.Small amount of presacral fluid is unchanged.OTHER: No significant abnormality noted.
1. No significant interval change in the right pelvic mass with extensive mass effect and soft tissue involvement as described.2. Stable involvement of the sciatic nerve to the level of the ischial tuberosity and tracking along the sacral plexus to the L5 and S1 right neural foramen.