History of right hemipelvis retroperitoneal mass. Evaluate for change. The reference predominantly fatty mass within the adductor musculature of the right hip extending through the obturator foramen to involve the obturator internus muscle, measuring approximately 12.3 x 6.2 cm, previously 12.3 x 6.2 cm in the transverse dimension upon remeasurement, not significantly changed. Additionally, the portion of the mass which extends through the obturator foramen demonstrates increased signal abnormality on T2-weighted images, appearing similar to the prior study which may represent small regions of necrosis but we see no dominant soft tissue nodule. The mass also appears to extend slightly into the acetabular fossa. We see no invasion of the bone. There are septations within the mass, some of which appear to show mild enhancement. There is also a small focus of increased signal abnormality internally within the mass on T2-weighted images which demonstrate minimal, if any, enhancement on postcontrast sequences, appearing similar to the prior study. The obturator nerve and artery are not well seen below the level of the pubic ramus. The mass results in slight lateral displacement of the right femoral artery and vein. There is also slight posterior displacement of the right sciatic nerve. The bone marrow signal intensity is within normal limits. Degenerative disc disease affects the visualized lower lumbar spine. There is low signal intensity within the uterus which likely represents fibroids, as seen on the prior study. There is also a mass with fat signal intensity within the left adnexal region which may represent a dermoid, appearing similar to the prior study.
Predominately fatty mass as described above, appearing similar to the prior study. Given the presence of enhancing septations and nonadipose elements, this raises the possibility of an atypical lipoma, although the relative stability suggests that this may simply represent a benign lipoma.